C-Nav IALA, C-NaviGator II, 3050, 2050, 1010 Hardware Reference Manual

DGNSS Systems Hardware Guide

www.cnavgnss.com

Contact the C-Nav® office or dealer

nearest you:

C-Nav Regional Office and Regional Distributor Contacts:

North America:

Lafayette, LA (Head Office): [phone]
Houston, TX: [phone]
Bothell, WA: [phone]
Mexico: [phone]

South America:

Rio de Janeiro - Sales: [phone]
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C-Nav Hardware Reference Guide

Updates to logos, contact information and
Adde d C2 Subscri p ti on Servic e de tai l s

Contact Info rm ati on

If you have a problem and cannot find the information you need during the installation or
operation of a C-Nav pro duct, cont act:

C-Nav Support:
Phone: [phone] (24/7 support)

Fax: [phone]

Phones are answered 24 hours, 7 days a week, with on-call technical support engineers
available.

E-mail: [e-mail]
Web: http://www.cnavgnss.com/

C-Nav Technical Support normal operational hours are 7am to 5pm, Monday through Friday
U.S. Central Standard Time. In addition, our regional offices can provide first line support for the
C-Nav DGNSS System.

Please reference your unit serial number (located on sticker on the front or side of the
DGNSS/DGPS receiver) when making any service calls.

Notices

C-Nav Hardware Reference Guide
Revision C
August 2011
© C&C Technologies, C-Nav World DGNSS, 2011.

Revision History

Rev. A (May 2009) Initial Release

Rev. B (October 2009) Adde d C-Nav3050 material

Rev. C (August 2011)

URL’s

3

C-Nav Hardware Reference Guide

Table of Contents

Contact Information .......................................................................................................................... 3

Notices ............................................................................................................................................... 3

Revision History ................................................................................................................................ 3

Table of Contents .............................................................................................................................. 4

List of Tab le s ..................................................................................................................................... 5

List of Fig ur es ................................................................................................................................... 6

Chapter 1 Overview ................................................................................. 8

C-Nav and Global Navigation Satell ite Systems .............................................................................. 8

Tr adition al Differentia l GNSS Position ing ........................................................................................................ 8

Sources of GNSS Error .................................................................................................................................. 8

Measuring GNSS Accuracy .......................................................................................................................... 10

Common Values Used with GNSS ............................................................................................................... 11

C-Nav Subscript ion Service.......................................................................................................................... 12

C-NavC2 Subscript ion Service ..................................................................................................................... 13

How to Access the C-Nav Subscription Service ............................................................................................ 14

L-band Correction Signal ............................................................................................................................. 15

Chapter 2 Installation Guide ................................................................ 17

C-Nav Antenna Installation Notice .................................................................................................. 17

Standard Antenna Installation ........................................................................................................ 17

Antenna Location ......................................................................................................................................... 17

Antenna Installation ..................................................................................................................................... 19

Coaxial Cable ................................................................................................................................... 21

Cable Route ................................................................................................................................................ 21

Coaxial Cable Ins t allation ............................................................................................................................. 21

Lightning Protection ....................................................................................................................... 23

GNSS Receiver ................................................................................................................................ 23

Chapter 3 C-Nav DGNSS Hardware Specifications ........................... 24

C-Nav3050 ........................................................................................................................................ 24

C-Nav3050 Receiver.................................................................................................................................... 24

C-Nav3050 Antennas................................................................................................................................... 26

C-Nav1010 ........................................................................................................................................ 30

C-Nav1010 Receiver.................................................................................................................................... 30

C-Nav1010 Antennas................................................................................................................................... 32

C-Nav2050 ........................................................................................................................................ 37

C-Nav2050 Receiver.................................................................................................................................... 37

C-Nav2050 Antennas................................................................................................................................... 40

C-Nav1000 ........................................................................................................................................ 45

C-Nav1000 Receiver.................................................................................................................................... 45

C-Nav1000 Display ...................................................................................................................................... 46

C-Nav1000 Antennas................................................................................................................................... 47

C-Nav1000 Display Mounting Options .......................................................................................................... 48

IALA GPS System ............................................................................................................................ 50

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C-Nav Hardware Reference Guide

IALA Receiver (MBX-3S, MBX-4) ................................................................................................................. 50

IALA Whip Antenna Dimensions ................................................................................................................... 52

C-NaviGator II .................................................................................................................................. 53

C-NaviGator II Cont r ol and Display Unit ........................................................................................................ 53

C-NaviGator II M ounting Options .................................................................................................................. 55

C-NaviGator II LCD Touch-screen Care and Cleaning .................................................................................. 62

Chapter 4 H ar dw are A cce ss or ie s ........................................................ 63

Huber + Suh ne r Lightning Protectors ............................................................................................ 63

Model No. 3403.17. 0045 Specifications ........................................................................................................ 63

Model No. 3403.17. 0045 Dimensions ........................................................................................................... 64

Model No. 3402.17. 0070 Specifications ........................................................................................................ 65

Model No. 3402.17. 0070 Dimensions ........................................................................................................... 66

Huber + Suhner Lightning Protector Mounting Instructions ............................................................................ 67

MOXA Converters ............................................................................................................................ 69

TCC-80I ...................................................................................................................................................... 69

TCC-80I Specifications ................................................................................................................................ 69

TCC-80I Dimensions.................................................................................................................................... 70

TCC-82 ....................................................................................................................................................... 70

TCC-82 Specifications ................................................................................................................................. 71

TCC-82 Dimensions .................................................................................................................................... 71

Times-Microwave LMR400 Coaxial Cable ...................................................................................... 72

LMR400 Specific at ions ................................................................................................................................ 72

LMR400 Connectors .................................................................................................................................... 73

Chapter 5 Technical Reference and Interface Guide ........................ 75

Coaxial Cable ................................................................................................................................... 75

Terminating Coaxia l Cable (Times Microwave Systems) ............................................................................... 75

Coax-Seal® Weather Sealant Installation ..................................................................................................... 79

Chapter 6 Glossary ............................................................................... 83

Troubleshooting .............................................................................................................................. 83

Abbreviations .................................................................................................................................. 86

Definitions ....................................................................................................................................... 89

List of Tables

Table 1-1: Common Accuracy Measures Used with GPS ...................................................................................................................... 11

Table 1-2: L-band Correction Identifiers and Modes ............................................................................................................................... 16

Table 1-3: C-Nav3050 Satellites Firmware Version 1.0.1.5 and Earlier ................................................................................................. 16

Table 1-4: C-Nav30 5 0 Satellites F ir m w are Version 2.0.22.0 and L ater ................................................................................................. 16

Table 2-1: Acceptable Coaxial Cable Lengths ........................................................................................................................................ 23

Table 3-1: C-Nav3050 Physical and Environmental ................................................................................................................................ 25

Table 3-2: C-Nav3050 I/O Messages....................................................................................................................................................... 25

Table 3-3: C-Nav3050 Connector Assignments ...................................................................................................................................... 25

Table 3-4: C-Nav3050 Standard, Base, and Airborne Antenna Specifications ...................................................................................... 26

Table 3-7: C-Nav1010 Physical and Environmental ................................................................................................................................ 31

Table 3-8: C-Nav1010 I/O Messages....................................................................................................................................................... 31

Table 3-9: C-Nav1010 Connector Assignments ...................................................................................................................................... 31

Table 3-10: C-Nav10 10 S t and ard Anten n a Sp ec if ications ...................................................................................................................... 32

Table 3-11: C-Nav10 10 L-band Antenna Specifications (45° - 25°) ....................................................................................................... 33

Table 3-12: C-Nav10 10 L-band Antenna Specifications (<25°) .............................................................................................................. 35

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C-Nav Hardware Reference Guide

Table 3-13: C-Nav20 50 P h ys ical and Envi ronment al.............................................................................................................................. 38

Table 3-14: C-Nav20 50 I /O M essages .................................................................................................................................................... 38

Table 3-15: C-Nav2050 Connector Assignments .................................................................................................................................... 38

Table 3-16: C-Nav20 50 S t and ard Antenna ............................................................................................................................................. 40

Table 3-17: C-Nav2050 Airborne Antenna .............................................................................................................................................. 40

Table 3-18: C-Nav20 50R Antenna ........................................................................................................................................................... 43

Table 4-1: Coax-Seal Product Specifications .......................................................................................................................................... 82

List of Figures

Figure 1-1: C-Nav Corrections Service Network Coverage .................................................................................................................... 15

Figure 2-1: C-N av3 050 Ant enn a Pr op er l y Ins t al l ed on M ast .................................................................................................................. 18

Figure 2-2: C-N av3 050 Ant enn a on M as t – Hose Clamp Installation .................................................................................................... 19

Figure 2-3: C-N av A n t enna Mountin g Pole Dimensions ......................................................................................................................... 20

Figure 2-4: C-Nav3050 Antenna TNC Connector ................................................................................................................................... 22

Figure 2-5: C-Nav3050 Antenna and Coaxial Cable ............................................................................................................................... 22

Figure 3-1: C-Nav3050 Base Plate Dimensions Without Mounting Brackets ........................................................................................ 24

Figure 3-2: C-Nav3050 Base Plate Dimensions With Mounting Brackets ............................................................................................. 24

Figure 3-3: C-Nav3050 Standard GNSS Antenna Offset ....................................................................................................................... 27

Figure 3-4: C-Nav3050 Standard (P/N NAV82-001020-3001) Antenna Dimensions ............................................................................ 27

Figure 3-5: C-Nav3050 Airborne (P/N NAV82-001022-3001LF) Antenna Dimensions ......................................................................... 28

Figure 3-6: C-Nav3050 Base (P/N NAV82-001021-3001LF) Antenna Dim ens ions .............................................................................. 28

Figure 3-7: C-Nav3050 Standard & Airborne Antenna Radiation Pattern .............................................................................................. 29

Figure 3-8: C-Nav3050 Base Antenna Radiation Pattern ....................................................................................................................... 29

Figure 3-9: C-Nav1010 Receiver wit h ou t M ounting Br ac k ets ................................................................................................................ 30

Figure 3-10: C-Nav1010 Receiver with Mounting Brackets .................................................................................................................... 30

Figure 3-11: C-Nav1010 Power Supply ................................................................................................................................................... 32

Figure 3-12: C-Nav1010 Standard Antenna Dimensions ....................................................................................................................... 33

Figure 3-13: C-Nav1010 Standard Antenna Radiation Pattern .............................................................................................................. 33

Figure 3-14: C-N av1 01 0 L-band Antenna Dimensions (45° - 25°) ......................................................................................................... 34

Figure 3-15: C-Nav1010 NAV82-001018-0001LF Ant en na Mountin g ( 45° - 25°) ................................................................................. 34

Figure 3-16: C-Nav1010 NAV82-001018-0001LF Radiation Pattern (45° - 25°) ................................................................................... 35

Figure 3-17: C-Nav1010 NAV82-001003-0001LF Ant en na and Moun ts (<2 5°) .................................................................................... 36

Figure 3-18: C-Nav1010 NAV82-001003-0001LF Radiation Pattern (<25°) .......................................................................................... 36

Figure 3-19: C-Nav2050 Front View ........................................................................................................................................................ 37

Figure 3-20: C-Nav2050 Top View .......................................................................................................................................................... 37

Figure 3-21: C-Nav2050 Power Supply ................................................................................................................................................... 39

Figure 3-22: C-Nav2050 RS-232 to DP RS-422 MOXA Converter (MOXTCC-801) ............................................................................. 39

Figure 3-23: C-Nav2050 Isolation Mount Adaptor................................................................................................................................... 39

Figure 3-24: C-Nav2050 Standard Antenna Phase Center Dimensions ................................................................................................ 41

Figure 3-25: C-Nav2050 Antenna Dimensions [inches (mm)] ................................................................................................................ 41

Figure 3-26: C-Nav2050 Airborne Antenna Dimensions ........................................................................................................................ 41

Figure 3-27: C-Nav2050 Standard & Airborne Antenna Radiation Patterns .......................................................................................... 42

Figure 3-28: C-Nav2050 Antenna Mounting Pole Adaptor Dimensions ................................................................................................. 42

Figure 3-29: C-Nav2050R Antenna Dimensions and Mounts ................................................................................................................ 43

Figure 3-30: C-Nav2050R Antenna Radiation Pattern............................................................................................................................ 44

Figure 3-31: C-Nav2050R Antenna LNA Wide-band Response ........................................................................................................... 44

Figure 3-32: C-Nav1000 Receiver Front View (mm) ............................................................................................................................... 45

Figure 3-33: C-Nav1000 Receiver Top View (mm) ................................................................................................................................. 45

Figure 3-34: C-Nav1000 Receiver Clearance Area ................................................................................................................................ 45

Figure 3-35: C-Nav1000 RS-422 to DP RS-232 MOXA Converter (MOXTCC-801) ............................................................................. 46

Figure 3-36: C-Nav1000 Display Front View (mm) ................................................................................................................................. 46

Figure 3-37: C-Nav1000 Display Top View (mm) ................................................................................................................................... 46

Figure 3-38: MGL-4 (H -field) Antenna ..................................................................................................................................................... 47

Figure 3-39: MGL-3 Antenna and Mounting Pole ................................................................................................................................... 47

Figure 3-40: Gimbal Mount Clearance Area............................................................................................................................................ 48

Figure 3-41: Panel Mount Frame Dimensions (mm) ............................................................................................................................... 48

Figure 3-42: Clear ance Distance Behind the Display ( P anel Mount) ..................................................................................................... 48

Figure 3-43: Panel Mount Hole Dimensions (mm) .................................................................................................................................. 49

Figure 3-44: Panel M ounting C-Nav1000 Display ................................................................................................................................... 49

Figure 3-45: C-N av1 00 0 D is pl ay P anel Mount ed.................................................................................................................................... 49

Figure 3-46: MBX-4 Rec eiver with M oun t i ng Bracket (Top Mount ed) ................................................................................................... 51

Figure 3-47: Bottom-view MBX-4 With Mounting Bracket (Bottom Mounted) ........................................................................................ 51

Figure 3-48: IALA Receiver Mounting Bracket Dimensions.................................................................................................................... 51

Figure 3-49: C-NaviGator II Display (Front View) ................................................................................................................................... 53

6

C-Nav Hardware Reference Guide

Figure 3-50: C-NaviGator II Side-panel Connectors ............................................................................................................................... 53

Figure 3-51: C-NaviGator II Power Supply .............................................................................................................................................. 53

Figure 3-52: RAM 100 75 VESA Base (w/ Steel Reinforce) / RAM-D-246U-IN1................................................................................... 55

Figure 3-53: RAM Doub l e S ock et Ar ms .................................................................................................................................................. 55

Figure 3-54: RAM 11" X 3" Base (w/ Steel Reinforce) / RAM-D-111B-IN1U (left) & ............................................................................. 55

Figure 3-55: Flat Screen Table Stand (for C-NaviGator II) / CHIFSB018BLK ....................................................................................... 56

Figure 3-56: Tilting VESA Wall Mount (for C-NaviGator II) / PEEST630 ............................................................................................... 56

Figure 3-57: Front Mount Kit (f or C-NaviGator II) / SYNIWO-6710-7CRBR2 ........................................................................................ 57

Figure 3-58: 19” Mounting Kit (for C-NaviGator II) / SYNIWO-6710-7CBR9 ......................................................................................... 58

Figure 3-59: C-NaviGator II (side USB-port model) Outline Diagram (mm)........................................................................................... 59

Figure 3-60: C-NaviGator II Cut-out Diagram (mm) ................................................................................................................................ 60

Figure 3-61: C-NaviGator II rev. A (front USB-port model) Outline Diagram (mm) ............................................................................... 61

Figure 4-1: Huber + Suhner Model No. 3403.17.0045 ............................................................................................................................ 64

Figure 4-2: Huber + Suhner Model No. 3402.17.0070 ............................................................................................................................ 66

Figure 4-3: Moxa TCC-80I Converter Dimensions .................................................................................................................................. 70

Figure 4-4: TCC-82 Converter Dimensions ............................................................................................................................................. 71

Figure 4-5: LMR400 Attenuation vs. Frequency Graph .......................................................................................................................... 73

Figure 4-6: LMR400 Connectors.............................................................................................................................................................. 73

Figure 5-1: Components for Termination of Coaxial Cable .................................................................................................................... 75

Figure 5-2: Prep/Strip Tool (large end) .................................................................................................................................................... 75

Figure 5-3: Duburring Tool ....................................................................................................................................................................... 76

Figure 5-4: Prep/Strip Tool (smaller end) ................................................................................................................................................ 76

Figure 5-5: RMA Flux Application ............................................................................................................................................................ 77

Figure 5-6: Soldering ................................................................................................................................................................................ 77

Figure 5-7: Connector Installation ............................................................................................................................................................ 78

Figure 5-8: Ferrule C rimping .................................................................................................................................................................... 78

Figure 5-9: RG-59U Coaxial Cable .......................................................................................................................................................... 79

Figure 5-10: Coaxial cable with Barrel Connector................................................................................................................................... 79

Figure 5-11: Coax-seal Roll ..................................................................................................................................................................... 80

Figure 5-12: Coax-seal Application.......................................................................................................................................................... 80

Figure 5-13: Coaxial Cable Fully Sealed ................................................................................................................................................. 81

Figure 5-14: Coax-seal Cross-section ..................................................................................................................................................... 81

Figure 6-1: DTE to DCE RS-232 Pin Assignments ................................................................................................................................. 92

7

C-Nav Hardware Reference Guide

Chapter 1 ....................................................................... Overview

C-Nav and Global Navigation Satellite Systems

Traditional Differential GNSS Positioning

Traditional Differential GNSS (DGNSS ) relies on the concept that errors in position at one
location are similar to those for all locations within a given (local) area. By recording GNSS
measur em e nts at a poi n t with known coordinates, the local GNSS observation errors can be
quantified and one pseudorange correction for each GNSS satellite observation can be
computed. By transmitting these pseudorange corrections to remote mobile users and applying
them in real-time, the remote mobile user accuracy of GNSS for instantane ous h or i zontal
positioning is reduced to less than 5 meters (and even sub-meter wit h mod ern commercial
survey grade GPS receivers) 95% of the time.

In traditional DGNSS, pseudorange corrections are generated at a reference station. By
transmitting these individual corrections for satellites all-in-view, the mobile user can apply the
pseudorange corrections for the common in-view satellites observed at the mobile location.

In order to minimize any errors that may be introduced, it is imperative that the reference station
and the mobile user are able to track the same GNSS satellites and thus the maximum baseline
distance is one limiting factor with traditional DG NSS. Another is that the accuracy of the mobile
user’s position will be degraded as the baseline distance separation between the reference
station and the mobile user increases. This is due to geographic spatial de-correlati on er r or s
introduced by the different ionospheric delays and GNSS satellite orbit biases between the
DGNSS reference site and each individual mobile DGNSS user. The reference station (or
network) computes not only a pseudorange correction (PRC) for each satellite, but also a range
rate correction (RRC). Thus, the mobile user is able to model the time varying characteristics of
the pseudorange corrections over the time intervals in which they are periodically generated at
the reference station and applied at the mobile locati o n (a ge o f cor r ection). DGNSS
pseudorange corrections combine together all errors produced by the GNSS satellite;
ephemeri s, clock, and atmosp her i c delays, at one time for the re f er e nce station position.

Sources of GNSS Error

GNSS user range error and bias sources can be identified as follows:

Ephemeris Data: Errors in the tracked location of a GNSS satellite in its orbit
Satellite Clock: Errors in a satellite’s atomic clock signal
Ionosphere: Errors caused by ionospheric path delay
Troposphere: Errors caused by tropospher i c path del ay
Multipath: Errors caused by reflected signals received by the GNSS antenna
Receiver: Errors in the measurement of time/range caused by thermal noise, computation

accuracy, and inter-channel bi ases

8

C-Nav Hardware Reference Guide

Ephemeris error occurs when the broadcast GNSS message for the satellite’s orbital location
is inaccurate. It is typical that the radial component of this error is the smallest; the along-track
and cross-track errors are larger by an order of magnitude. The ‘line of sight’ projections of the
GNSS satellite positioning error affect each GNSS observation differently. Ephemeris errors
reflect a position prediction and tend to grow with time from the last GNSS Ground Control
Segmen t st ati o n upl o ad .

Satellite Clocks ar e fundamental to the GNSS system so that the one-way ranging
measurement process can be accomplished. Each satellite broadcasts it’s own clock
adjustment values to allow the user to develop accurate GNSS satellite clock predictability
models . Thes e sa tel l it e cloc k er r or s affect both the C/A an d P-code users in the same way,
which result in a residual clock error for each GNSS satellite. All GNSS observers receive an
identical satellite clock error.

Ionospheric errors or delays are unique to th e lo cal are a for each GNSS observer, and are
introduc e d du e t o free electrons in the ionosphere. The modulation on the signal is delayed in
proportion to the number of free electrons encountered. The ionosphere is usually reasonably
well behaved and stable in the temperate zones; however, near the equator or magnetic poles it
can fluct ua te c o nsi derably. This local er r or can be resolved by t he us e of dual frequ ency, L1 and
L2, observations by the GNSS observer.

Survey-quality receivers will correct the raw pseudorange for the ionospheric delay. The
simplest correction employs an internal diurnal model of these delays. For Single Frequency (L1
only) GNSS users, the parameters can be updated using information in the GNSS correction
'communications message'. The effective accuracy of this modeling is about 2-5 meters in
ranging for users in the temperat e zo nes .

A second technique for dual-frequency P-code receivers is to measure the signal at both
freque nci es an d di r ectl y sol v e for th e del ay. The differenc e betw e en L1 and L2 ar r iv al times
allows a direct solution. This dual-frequency technique typically provides 1 meter or better in
ranging accuracy, due to the ionosphere, for a well-calibrated receiver.

A third technique relies on a real-time ionospheric model providing corrections with accuracy of
1-2 meters or better in temperate zones.

Note: The solar 11-year activity cycle also affects the ionosphere and causes 'scintillation'
effects, which are problematical along the geo-magnetic equator when the solar cycle is at its
peak.

Tropospheric errors are deviations in the velocity of the GNSS signal as it passes through the
troposphere, and are unique to the local area for each GNSS observer. Variations in
temperature, pressure, and humidity all contribute to variations in the speed of radio waves.
Both the code and carrier will show the same delays, and use of a reliable model can reduce
most of this error. For most users and circumstances, a simple model should be effectively
accurate to about 1 meter or better.

Multipath Errors are caused by reflected signals entering the antenna of the GNSS receiver
and masking the real correlation peak. These effects tend to be more pronounced in a static

9

C-Nav Hardware Reference Guide

receiver near large reflecting surfaces. The first line of defense is to use the combination of
antenna cut-off angle and antenna location in order to minimize the problem. A second
approach is to utilize software algorithms within the receiver to minimize the impact of multipath
on range trac ki ng accuracy. With proper location and antenna selection, the net impact to a
moving user should be less than 1 meter under most circumstances.

Receiver Errors vary from GN SS unit to GNSS u ni t. Initially most commercial GPS receivers
were 'sequential', in that one or two tracking channels shared the burden of locking on to four or
more satellites. As chip technology improved, it was common to place three or more tracking
channels on a single chip. As the size and cost have decreased, techniques have improved and
'parallel' multi-channel receivers are common. Most modern GNSS receivers use an all-digital
design allowing very low signal noise and phase tracking solutions. This produces a precision of
better than 0.3 meter. Inter-channel bias is minimized with digital sampling and all-digital
designs. The net result is that survey-quality GNSS receivers now contribute less than 0.5­meter error in bias and l ess tha n 0.2 meter s in n oi se.

Measuring GNSS Accuracy

The fundam ental and basic req uir em ent of compari ng geo gr a phic locations and coordinates is
that the reference coordinate system and datum transformation are known. The GPS system
functions within the Earth-Centered, Earth-Fixed World Geode tic System 1984 (WGS84)
ellipsoid and Cartesian coordinate system. GNSS receivers internally transform the Cartesian
data into degrees (Latitude and Longitude) with the vertical height expressed in meters above
the reference ellipsoid. Therefore, when comparing coordinate values for any location in the
world, suc h as a ma p pos i tion or feature, a physical survey marker or reference location, the
data and observations must be referenced to the same datum and coordinate system.

For example, in North America, there are two different datum models in common usage. These
are the North American Datum of 1927 (NAD27) and the North American Datum of 1983
(NAD83). A physical geographic feature on the surface will have entirely different coordinate
latitude and longitude values when expressed in each of the NAD-27 and NAD-83 da t um s.

The GNSS user is entirely responsible for understanding that a measured position using the
GNSS system (WGS84) requires transformation if the final coordinates are to be expressed in a
geodetic system other than WGS84. Ignorance of this fact will lead to significant er r or s in th e
desired positional output and is often considered to be a result of the greatest source of error in
GNSS, human error.

Another major factor affectin g an au to nomous GNSS position is the GN SS Satelli te positi o n
geometry an d vis i bility to the user, and a quality measure given by the Dilution of Precision
(DOP) indices provided by all GNSS receivers.

• GDOP - Geometric Dilution of Precision

• TDOP - Time Dilution of Precision

• PDOP - Position Dilution of Precision

• HDOP - Horizontal Dilution of Precisi o n

• VDOP - Vertica l Dilution of Precision

10

C-Nav Hardware Reference Guide

SEP – also

probably err or

The followi n g t a bl e desc r i b es s om e of th e stat is ti cal formulas and me asures commonly us ed f or
GNSS posi ti on al ac cur a c y measurement:

Table 1-1: Common Ac curacy Measures Used w ith GPS

Measurement

Dimension

1D

1D

2D

2D

2D

Statistical

Measure

Root Mean

Square

Probable

Error

Error

Ellipse

Circular

Error

Probable

Twice

Distance

Root Mean

Square

Abbreviation Probability Approximation

rms 68.3%* σ

PE 50%* 0.674 σ** N/A

2

x

x

+ σ

+ σ

x

, σ

)*

y

†

2

y

N/A 39.4%*

CEP 50%*

2drms

Varies, 95.4

– 98.2%

Defined by σ

0.589 (σ

†

& correlation

Radius:

Radius: 2σ

σ = √ σ

Related

Expressions

MSE – mean

square er r or

(the squar e o f

the rms)

y

N/A

CPE – also

called circula r

probable error

nd

2

, less

common

definiti o n: 2
dimensional
rms (circle’s

radius 1 σ)

3D

Error

Ellipsoid

N/A 19.9%*

Spherical

3D

Error

SEP 50%*

Probable

*(Mikhail, 1976) †( Langley, 1991 ) **(National Ge odetic Survey, 1986)

Common Values Used with GNSS

• Speed of light ….. c = 299792458 meters per second

• L1 freque ncy …. .. f

• L2 freque ncy …. .. f

= 1575420000 H z

L1

= 1227600000 H z

L2

• Wavelength ……. λ = c/f (meters per second)

• L1 wavelength …. λ

• L2 wavelength …. λ

= 0.190293672798 meters

L1

= 0.244210213425 meters

L2

11

Defined by :

σx, σy, σ

z

&

correlations

Radius:

0.513 (σx + σ
σ

)*

z

y

+

N/A

called

spherical

C-Nav Hardware Reference Guide

C-Nav Subscription Service

Description

The C-NavC
Services are a global system for the distribution
of SBAS corr ec ti o ns gi vi ng t he user the ability to
measure their position anywhere in the world
with excep ti onal reliability an d un pr ec e de nted
accuracy of better than 10cm (2ơ). Because the
SBAS corrections are broadcast via INMARSAT
geo-stationary satellites, the user needs no local
reference stations or post-process ing to get this
exceptional accuracy. Furthermore, the same
accurac y is av ai l a bl e vi r tual l y any where on the
earth's surface on land or sea from 72°N to 72°S
latitude, due to the worldwide coverage of these
geo-stationary satellites.

Infrastructure

1

and C-NavC2 Subscription

The system utilizes GNSS satellite systems, L-Band communication satellites, and a worldwide
network of reference stations, to deliver real-t im e hi gh-precision positioning.

To provide this unique service, C-Nav has built a global network of multi-frequency reference
stations, which constantly receive signals from GNSS satellites as they orbit the earth. Data
from these reference stations is fed to two USA processing centers, in Torrance, California and
Moline, Illinois, where they are processed to generate the differential corrections.

From the two processing centers, the correction data is fed via redundant and independent
communication links to satellite uplink stations at Laurentides, Canada; Perth, Austr al i a; Burum,
The Netherlands; Santa Paula, California; Auckland, New Zealand; and Southbury, Connecticut
for rebroadcast via the
geo-stationary satellites.

The key to the accuracy and convenience of the C-Nav Subscription Service is the source of
SBAS corrections. GNSS satellites transmit navigation data on several L-Band fr eq ue nc i es

1

.
The C-Nav reference stations are all equipped with geodetic-quality, multi-frequency receivers.
These reference receivers decode GNSS signals and send precise, high quality, m ult i­frequency pseudorange and carrier phase measurements back to the processing centers
together with the data messages, which all GNSS satellites broadcast.

At the processing centers, C-Nav's pr opr ietary differen ti al pr oc essing techniqu es are us e d t o
generate real-time precise orbits and clock correction data for each satellite in the GNSS
constellations. This proprietary Wide Area DGNSS (WADGNSS) algorithm is optimized for a
multi-frequency system such as the C-Nav Subscription Service, in which multi-frequency
ionospheric measurements are available at both the reference receivers and the user receivers.
It is the use of multi-frequency receivers at bo th t h e re fer e nc e st a ti on s and the us er eq ui pm e nt,

1

A single-frequency operation mode is av ailable for the C-Nav3050. Contact C-Nav Support for details on using this
feature. Si ngle-frequency is a receiver mode that uses only the L1 GPS/G1 GLONASS signals. There is no
compensation for ionospheric effects.

12

C-Nav Hardware Reference Guide

together with the advanced processing algorithms, which makes the exceptional accuracy of the
C-Nav Subscription Service possible.

Creating the corrections is just the first part. From our two processing centers, the differential
corrections are then sent to the Land Earth Station (LES) for uplink to L-Band communications
satellites. The uplink sites for the network are equipped with C-Nav-built mod ul ati o n eq ui pm e nt,
which interfaces with the satellite system transmitter and uplinks the correction data stream to
the satellite that broadcasts it over the coverage a r ea. E ac h L-Band satellite covers more than a
third of the earth.Users equipped with a C-Nav precision GNSS receiver actually have two
receivers in a single package, a GNSS receiver and an L-Band communications receiver, both
designe d by C-Nav for this system. The GNSS receiver tracks all the satellites in view and
makes pseudorange measurements to the GNSS satellites. Simultaneously, the L-Band
receiver receives the correction messages broadcast via the L-Band satellite. When the
corrections are applied to the GNSS measurements, a position measurement of unprecedented
real-tim e ac cur a c y is produced.

Reliability

The entire system meets or exceeds a target availability of 99.99%. To achieve this, every part
of the i nfrast r ucture has a built-in back-up system.

All the reference stations are built with duplicate receivers, processors and communication
interfaces, which switch automatically or in response to a remote control signal from the
processing centers. The data links from the reference stations use the Internet as the primary
data link and are backed up by dedicated communications lines, but in fact the network is
sufficiently dense that the reference stations effectively act as back up for each other. If one or
several fail , th e net effect on the correction accuracy is not impaired.

There are two continuously running processing centers, each receiving all of the reference site
inputs and each with redundant communications links to the uplink LES. The LESs are
equipped with two complete and continuously operating sets of uplink equipment arbitrated by
an automatic fail over switch. Finally, a comprehensive team of support engineers maintains
round the clock monitoring and control of the system.

The networ k is a f ul ly aut om ated self-monitoring system. To ensure overall system integrity, an
independent integrity monitor receiver, similar to a standard C-Nav user receiver, is installed at
every reference station to monitor service quality. Data from these integrity monitors is sent to
the two independent processing hubs in Torrance, California and Moline, Illinois. Through these
integrity monitors the network is continuously checked for overall SBAS positioning accuracy, L­Band signal strength, data integrity and other essential operational parameters

C-NavC2 Subscription Service

C-Nav now offers a second independent full constellation (GPS + GLONASS) GNSS correction
service called C-NavC
as orbit correctors (Galileo and COMPASS planned). It provides a fully independent suite of
clock and orbit correction algorithms, and fully independent servers in geographically separated
processing centers. Features also include a second independent global network of C-Nav dual
frequency GPS / GLONASS reference stations equipped with Sapphire© based technology, and
simultaneously broadcasts from two independent satellite networks (Net -1 and Net-2).

2

. C-NavC2 features include GLONASS and GPS (GNSS) clock, as well

13

C-Nav Hardware Reference Guide

The C-Nav Subscription Service, now called C-NavC1, remains unaffected and continues to
provide customers with full GPS clock and orbit correctors. C-NavC

1

has proven reliability since
2000, featuring JPL/NASA clock and orbit based C-Nav proprietary correction algorithms, a
global network of dual frequency reference sites, fully independent servers in geographi cally
separated processing centers and simultaneous broadcasts from two independent satellite
networks (Net-1 and Net-2) to ensure a reliable worldwide positioning solution.

The C-Nav3050 receiver combined with the C-NavC

2

subscription service deliv er s PPP
corrector s for all operational GNSS satel l i tes, showing significantl y en ha nced performanc e in
shaded conditions and increased position accuracy. There is up to 20 percent reduction in PPP
start-up pull-in time accuracy, now with two completely independent solutions available (C-

1

NavC

and C-NavC2). There ar e no ad di ti onal fees for access to the new C-NavC2 correction

service, giving users the best of both worlds.

How to Access the C-Nav Subscription Service

C-Nav is a subscription service. The user pays a subscription, which licenses the use of the
service f or a pre determined peri od of time.

Subscriptions can be purchased for any predetermined period of time and are available via a C­Nav authorized representative, or by contacting C -Nav at: [e-mail]

An authorized subscription will provide an encrypted key, which is specific to the Serial Number
of the C-Nav receiver to be authorized. This is entered into the receiver using a C-Nav controller
solution such as the C-NaviGator II CDU, C-Monitor or C-Setup PC software, or Over the Air (C­Nav3050 only).

When contacting C-Nav regarding subscription or deactivation of service, please have the
following information available:

 Company Name and Contact Information
 PO/Reference No.
 Vessel Name, Location and No. (if applicable)
 Required Star t/Stop Date or Period
 Service Type (Land or Offshore/Activation or Deactivation)
 Operational Region
 Rece ive r Type

The only piece of equipment needed to acc ess the C-Nav system is a C-Nav receiver. C-Nav
offers a variety of receivers configured for different applications. Details of all the C-Nav
receiver s ar e available from a C-Nav authorized local representative or on the C-Nav website at:

www.cnavgnss.com/products

For online ac ti vation and dea ctivati on, go to: http://www.cnavgnss.com/code

14

C-Nav Hardware Reference Guide

Figure 1-1: C-Nav Corrections Service Network Coverage

L-band Correction Signal

C-Nav DGNSS Receivers can obtain C-Nav sign als from six (6) separ a te an d i nd ependent geo­stationary communication satellites.

The Satellite Based Augmentation System (SBAS) signals obtained from geo-stationary
communication satellites are selected by GPS L1 PRN ID.

The L-band Identif iers for the tracking and decoding of these corrections by C-Nav GNSS/ GPS
Receivers are as follows:

15

C-Nav Hardware Reference Guide

Geo-stationary

Position

Am-1

Americas Net-1

YES

NO

97.65° W

EuA-1

Europe/Africa Net-1

YES

NO

25° E

Pac-1

Asia/Pacific Net-1

YES

NO

109° E

Am-2

Americas Net-2

YES

NO

142° W

EuA-2

Europe/Africa Net-2

YES

NO

15.5° W

Pac-2

Asia/Pacific Net-2

YES

NO

143.5° E

PRN 120

Inmarsat-3-F2/AOR-E

NO

EGNOS

15.5° W

PRN 124

ARTEMIS

NO

EGNOS

21.5° E

PRN 126

Inmarsat-3-F5/IOR-W

NO

EGNOS

25° E

PRN 127

Imarsat-4-F1/IOR

NO

GAGAN

82° E

PRN 129

MTSAT-1R

NO

MSAS

140° E

PRN 137

MTSAT-2

NO

MSAS

145° E

PRN 135

Intelsat Galaxy XV

NO

WAAS

133° W

PRN 138

TeleSat Anik F1R

NO

WAAS

107.3° W

Satellite

Name

402

97.65W

PAC-E

Laurentides

609

109E

IND-E

Auckland

525

25E

IND-W

Burum

358

142W

PAC-C

Santa Paula

643

143.5E

PAC-W

Perth

484

15.5W

AOR-E

Southbury

Satellite

402

97.65W

PAC-E

Laurentides

643

143.5E

PAC-W

Perth

525

25E

IND-W

Burum

358

142W

PAC-C

Santa Paula

609

109E

IND-E

Auckland

484

15.5W

AOR-E

Southbury

Table 1-2: L-band Correction Identifiers and Modes

L-band ID SV Name RTG SBAS

Note: See the L-band Communication Satellite Locator HTML utility:

http://www.cnavgnss.com/calculator

Table 1-3: C-Nav3050 Satellites Firmware Version 1.0.1.5 and Earlier

Network Satellite ID Longitude

Net 1

Net 2

Table 1-4: C-Nav3050 Satellites Firmware Version 2.0.22.0 and Later

Network Satellite ID Longitude

Net 1

Net 2

Satellites 609 (Asia/Pacific Net-1) and 643 (As ia/Pacific Net-2) have been reassigned to provide
improved reception. Satellite 609, which was Net-1, is now in Net-2, and satellite 643, which
was in Net-2, is now Net-1.

Name

Uplink Site

Uplink Site

16

C-Nav Hardware Reference Guide

Chapter 2 ........................................................... Installation Guide

C-Nav Antenna Installation Notice

This manual provides guidance on hardware installation for optimum performance.
Prior to commencing any installation, discuss proposed mounting locations/methods and cable

routes with the vessel chief engineer or master to ensure that all parties are aware of the work
to be done and th e ri sk s in v ol ve d.

Always wear ap pr opr i a te pr o t ecti ve equipment, in cl udi n g a certified fall arrestor harness

and hardhat when working at heights to prevent injury to personnel, or death. Prior to
commencing any work on the mast, ensure that all radar systems are switched off and
isolated.

Standard Antenna Installation

Antenna placement is critical to good system performance. It is necessary to mount the antenna
as high on the mast as possible in order to avoid antenna shading by surrounding structures.

Antenna Location

When choosing an antenna location, consider the following:

 Locate the antenna as high on the mast as possible, where it has a clear view of the sky,

to an elevati o n an gl e of 7º if possible. Obstructio ns below 15º elevation generally are not
a problem, though this is dependent on satellite availability for the local region.

 Avoid placing the antenna where more than 90º azimuth of the sky is obstructed. When

more than 90º of azimuth is shaded, it is often still possible for the reciever to navigate,
however, poor satellite geometry (due to satellite shading) will provide poor positioning
results.

 Avoid placing the antenna on or near metal or other electrically reflective surfaces.
 Do not paint the antenna enclosure with a metallic-based pai nt.
 Secure the antenna to the mast firmly to avoid wind and vibration which can affect the

performance of the system.

 Avoid placing the antenna near electrical motors (generators, air conditioners,

compressors, etc.) or other sources of interference such as radar systems, satcom
domes, HF antennas or whip antennas.

 Do not place the antenna too close to other active antennas. The wavelength of L1 is

0.19m and L2 is 0.244m. The minimum acceptable separation between antennas is 1m
(39 in), which provides 6dB of isolation. For 10dB of isolation, separate the GPS
antennas by 2.5m (8ft), and for 13dB of isolation (recommended) separate the antennas
by 5m (16ft).

17

C-Nav Hardware Reference Guide

 Active antennas (those with LNA’s or am plifiers) create an el ec tr i cal field around the

antenna. These radiated emissions can interfere with other nearby antennas. Multiple
GPS antennas in close proximity to each other can create multipath and oscillations
between the antennas. These ad d to pos ition error or the inability to process the satellite
signals

 Use satellite prediction software with a recent satellite almanac to assess the impact on

satellite visibility at your location. An L-Band Communication Satellite Locator tool is
availabl e on C-Nav’s website to aid in determining potential obstructions to C-Nav
Corrections Service Signals: www.cnavgnss.com/calculator

 A clear line of sight between the antenna and the local INMARSAT satellite is required to

track C-Nav signals. INMARSAT satellites are geo-synchro ni z e d 35,786kms above th e
Equator, currently at Longitudes:

142° West, 97. 65° West, 15.5° West, 25° East, 109° East, 14 3.5° East.

Figure 2-1: C-Nav3050 Antenna Properly Installed on Mast

18

C-Nav Hardware Reference Guide

Hose

Coaxial

Antenna

Notice

Antenna Installation

1. Once the antenna location has been determined based on the previously mentioned
criteria, mount the antenna onto the antenna mounting pole
deck prior to climbing the mast as mounting the antenna aloft poses potential risks to
personnel and equipment due to possible dropped object hazards. (Note: C-Nav2050 &
C-Nav3050 Antennas require an Antenna Mounting Adaptor, supplied).

The threads of all ant e nn a mo unt ing poles are 1”-14 in size

2. Install the antenna with the antenna mounting pole in the predetermined location. The
pipe can either be welded to the mast for a more permanent installation, or secured
using stainless steel hose clamps. In the figure below, hose clamps have been used.

. This should be done on

Antenna

has 360°

view of the

sky

Cable

Connected

to

Clamps

Figure 2-2: C-Nav3050 Antenna on Mast – Hose C l am p Inst allation

3. Use a level to ensure that the antenna is mounted vertically.

19

C-Nav Hardware Reference Guide

Figure 2-3: C-Nav Antenna Mounting Pole Dimensions

20

C-Nav Hardware Reference Guide

Coaxial Cable

Proper installation of coaxial cables is important to ensure successful communication between
the antenna and the GNSS Receiver.

Cable Route

When choosing a cable route for coaxial cable, co ns ider t h e fol l ow ing:

 Avoid running coaxial cable across, or paral l el t oo pow er cables and high power RF

cables.

 Ensure that the cable route is free of and sharp edges or places where the cable could

become pi nc hed or damaged in any way.

 Determine the manufacturers specifications for the coaxial cable in use. This should

include: impedance, diameter, attenuation in dB/100ft and dB/100m at the applicable
frequency, velocity of propagation and the minimum bend radius of the cable.

 Ensure the cable does not exceed the recommended minimum bend radius suggested

by the manufacturer.

 Ensure there is sufficient space at the cable entry point to the bulkhead as to not

damage the connector during installation.

 Measure the length of the cable route and refer to Table 2-1 for acceptable cable lengths

in relation to attenuation loss at the frequencies in use. For best performance, do not
allow more than 7dB (18dB for C-Nav 1000) of cable loss be tw een the antenna and th e
receiver; lower elevation satellite tracking suffers the most with more than 7dB insertion
loss.

 In-line amplifiers suitable for all GNSS frequencies may be used to increase the length of

the antenna cable, but care should be exercised that tracking performance is not
degraded due to multiple connections, noise from the amplif ier, and possible ingress of
moisture and dust to the in-line amplifier. In-l i ne a m pl ifier or spli tter devices must pass
DC power from the receiver to the antenna, or source the appropriate voltage and
current to the antenna In-l ine am pl ifiers may also over-saturat e the recei ver fr ont-end if
improper ly used.

Coaxial Cable Installation

1. P r ior to connecting the coaxial antenna cable to the antenna, ensure that all connections
are free of dir t and other debr i s. A p pl y sil i cone grease to the con nector threads and wip e
off any excess, ensure not to get any lubricant on the contact. Connect the coaxial cable
and tighten firm l y. Wr ap th e c on nect ion with self-amalgamating tape or another weather
sealant such as Coax-seal

® to prevent water ingress.

21

C-Nav Hardware Reference Guide

Zip-ties securing

Notice the slack in
Excess Coaxial

Figure 2-4: C-Nav3050 Antenna TNC Connector

2. Slacken the coaxi al cable and attach to the antenna mounting pol e wi th a zi p-tie. This
will prevent any undue strain on the cable connector and antenna.

3. With the cable connected to the antenna, run the cable down the mast, securing with zip
ties every 3 or 4 feet.

Figure 2-5: C-Nav3050 Antenna and Coaxial Cable

4. Carefully lay the cable along the chosen route to further detect any potential kinks,
bends or spots where the cable may become damaged.

5. Secure the cable along the cable route with ta pe o r zip ties and plac e a la bel at th e
GNSS receiver end of the cable for identification purposes.

the cable, done to
prevent un due
stress on th e
connections

coaxial cable in
place (cable runs
along oppos i t e
side of mast)

Cable neatly
stowed

6. Connect the coaxial cable to the TNC connector on the GNSS receiver. Ensure that any
slack in the cable is neatly stowed and that the minimum bend radius is not exceed
during this process.

22

C-Nav Hardware Reference Guide

Cable Type

dB Loss per 100'

dB Loss per 100m

7dB Loss Point

18dB Loss Point*

RG-174

34.77

114.075

20.132' (6.136m)

51.769' (15.779m)

RG-58

19.608

64.331

35.700' (10.881m)

91.799' (27.980m)

RG-213

9.566

31.385

73.176' (22.304m)

188.166' (57.353m)

RG-8

9.566

31.385

73.176' (22.304m)

188.166' (57.353m)

LMR240

10.128

33.228

69.115' (21.066m)

177.725' (54.171m)

Table 2-1: Acceptable Coaxial Cable Lengths

RG-223 17.226 56.516 40.636' (12.386m) 104.493' (31.850m)
RG-142 16.496 54.121 42.435' (12.934m) 109.117' (33.259m)

RG-214 9.526 31.253 73.483' (22.398m) 188.957' (57.594m)

LMR195 14.904 48.898 46.967' (14.316m) 120.773' (36. 812m)

LMR400 5.263 17.267 133.004' (40.540m) 342.010' (104.245m)
LMR600 3.408 11.181 205.399' (62.606m) 528.169' (160.986m)

*Note: 18dB Loss Point applies to the C-Nav1000 System only, all other C-Nav GNSS/GPS Systems should not
experience signal loss gr eater than 7dB

Lightning Protection

Where the GNSS antenna is exposed to sources of electromagnetic discharge such as

lightning, install a properly grounded in-line electrical surge suppressor between the
GNSS receiver and antenna. Install protective devices in compliance with local
regulator y co des an d pr ac ti ces. Protectiv e devi c e s must pass DC pow er from the
receiver to the antenna. Contact C-Nav Sup por t or refer to Chapter 4 of this gui de for
more information on available lightning protection solutions.

GNSS Receiver

GNSS receivers are best installed using the mounting brackets provided. When choosing a
location for GNSS Receiver installation, consider the following:

 Avoid placing the receiver in direct sunlight, places with inadequate ventilation, or where

it might be subject to excessive dust.

 Ensure the receiver is mounted securely to a flat surface in an area with little vibration.

Shock isolators suitable for 1.8kg (4lbs) may be necessary for environments with high
vibration.

 Do not place the receiver in a confined space or where it may be exposed to excessive

heat, moisture, or humidity.

 Install the receiver in a location with easy access to both the front and back panels.
 Refer to applicable C-Nav Product User Guide for GN SS/GPS Receiver-specific setup

and configur ation.

23

C-Nav Hardware Reference Guide

Chapter 3 ........................ C-Nav DGNS S Hardware Specifications

C-Nav3050

C-Nav3050 Receiver

Figure 3-1: C-Nav3050 Base Plate Dimensions Without Mounting Brackets

Figure 3-2: C-Nav3050 Base Plate Dimensions With Mounting Brackets

24

C-Nav Hardware Reference Guide

Control Commands
RTCM 2.3 and 3.0, RTCM types 1, 3, and 9, SBAS (WAAS/EGNOS/ MSAS/

CMR/CMR+, RTCM types 18-22, and 1001-1006, 1009-1012, 1014-1017; NCT

NMEA-0183 Messages

Table 3-1: C-Nav3050 Physical and Environmental

Without Mounting Brackets:
164 x 117 x 60mm

Size (L x W x H):

Weight: 1.1 lbs (0.50 kg)
External Power:

Input Voltage:
Output Voltage:

Temperature (amb ient)

Operating:
Storage:

Humidity: 95% Non-Condensing
Vibration:

Shock:
Ingress Protection: IP67 (compliant only when cables are connected)

Mar ine Equipment : Marin e Equipment Dir ective (MED ) 96/ 98/E C

(6.47 x 4.60 x 2.37in)
With Mounting Brackets:
164 x 166 x 62mm

(6.47 x 6.52 x 2.46in)

9 to 32VDC, 6W typical
+5V ± 0.5V (up to 100mA available for antenna bias via RF connector)

-40ºC to +70ºC ( -40º to + 158º F)

-40ºC to +85ºC ( -40º to + 185º F)

MIL-STD-810F
Method 514.5

MIL-STD-810F
Method 516.5

Table 3-2: C-Nav 30 50 I/O Mess ag es

(Input Only):
Differential Correction (I/O):

RTK C orrection Data (I/O):

(O utput O nly):

C-Nav proprietary commands (contact C-Nav Support f or more information)

GAGAN), and C-Nav

types 0x5B, 0x5C and 0x5E (hex)

ALM, ML A, GBS, GGA , GLL, GRS, GSA, GST, GSV, RMC, RRE, VTG, ZDA

Table 3-3: C-Nav 30 50 C on nector Assignme nts

ANT: TNC (fema le)

RF Input, RF G r ound

COM 1 – LAN: Pos i tronic (female)

RS-232, from 9.6 to 115.2kbps, Ethernet, from 10 to 100Mbps, 1PPS

COM 2 – USB: Posi tronic (female)

RS-232/RS-422, from 9.6 to 115.2kbps, USB 2.0, 12Mbps max data rate

POWER: Pos i tronic (male)

Power port, from 9 to 32 VDC, 6W typical, Power Input 1,2; Power Ground
1PPS / Event Marker

Bluetooth: 1 Serial Port Service, 230.4kbps

10m (32 ft) range

25

C-Nav Hardware Reference Guide

C-Nav3050 Antennas

Table 3-4: C-Nav3050 Standard, Base, and Airborne Antenna Specifications

Part Numbers Standard: NAV82-001020-3001LF

Base: NAV82-001021-3001LF
Airbor ne: NAV82-001022-3001LF

Frequency
(Frequency is dependent on

software bundle opt ions.)

Phase Centre
(see Fig ure 3-3)

Polarization Right Hand Circul ar (RHCP)
Pre–Amplifier 39dB gain (+/-2dB)
Noise Figure 2.6dB max
Impedance 50 Ohms
VSWR / RL
Band Rejection 20dB @ 250MHz
RF Power Handling 1 Watt
Input Voltage 4.2 to 15.0 VDC

GPS L1: 1575.42MHz, ±16MHz
GPS L2: 1227.60MHz, ±16MHz
GPS L2C: 1227.60MHz, ±16MHz
GPS L5: 1176.45MHz, ±16MHz
C-Nav L-Band: 1525 -1585 MHz
GLONASS G1: 1603.00MHz , ±6.5MHz
GLONASS G2: 1247.00MHz , ±5MHz
Galileo E1: 1575.42MHz , ±16MHz
Galileo E5A: 1176.45MHz, ±12.5 MHz

GPS L1: 66mm (2.60in)
GPS L2: 65mm (2.56in)

≤ 2.0:1 (14dB return loss)

Power Consumption 0.3W 46mA typical, 50mA max @ 5VDC
Vibration* RTCA D0-160 E, S ecti on 8, Curve D
Immersion MIL-STD-810F, Method 512.4
Cable Connector TNC Female
Antenna Operating

Temperature
Altitude 70,000ft; 21,336m
Rover/Airborne Antenna Finish Fluid resistant Ultem, UV stable

• Designed to DO-160D St andard

• P/N NAV82-001022-3001LF is the aircraft mount antenna, also rated to 70,000

feet (21,336m), and is TSO-C144 ce r tified.

-55°C to +85°C

26

C-Nav Hardware Reference Guide

Figure 3-3: C-Nav3050 Standard GNSS Antenna O ffs e t

• Figure 3-3 is a drawing of the label on the Standard GNSS antenna (P/N NAV82-
001020-3001LF). The phase center provided is based on NGS test results. NGS does
not currently provide GLONASS calibrated values.

• To achieve the greatest level of accuracy, the absolute phase center values

must be incorporated into your processing. Phase center information on all C­Nav3050 antennae is found on the NGS website:

http://www.ngs.noaa.gov/cgi-bin/query_cal_antennas.prl?Model=NAV

Figure 3-4: C-Nav3050 Standard (P/N NAV 82-001020-3001) Antenna Dimensions

27

C-Nav Hardware Reference Guide

Figure 3-5: C-Nav3050 Airborne (P/N NAV82-001022-3001LF) Antenna Dimensions

Figure 3-6: C-Nav3050 Base (P/N NAV82-001021-3001LF) Antenna Dimensions

28

C-Nav Hardware Reference Guide

Figure 3-7: C-Nav3050 Standard & Airborne A nt e nna Radiation Pattern

• Optimal an t e nn a performance is real iz e d at el ev a tions greater than 25º.

• There is a 10dB variation between 0º and 90º elevation (factor 10x); therefore, lower

elevation satellites are always more difficult to track.

• There is a 5dB variation between ~35º and 0º elevation (factor >3x)

Figure 3-8: C-Nav3050 Base Antenna Radi ati o n Pat t er n

• Optimal an t e nn a performance is real iz e d at el ev a tions greater than 35º.

• There is a 11dB variation between 15º and 90º elevation (factor >10x); therefore, lower

elevation satellites are always more difficult to track.

• There is a 9dB variation between ~35º and 0º elevation (factor >8x)

29

C-Nav Hardware Reference Guide

C-Nav1010

C-Nav1010 Receiver

Figure 3-9: C-Nav1010 Receiver without Mounting Brackets

Figure 3-10: C-Nav1010 Receiver with Mounting Brackets

30

C-Nav Hardware Reference Guide

Size (L x W x H) : w/o Brack et

< 8.3 x 4.7 x 2. 5(in) (211 x 119.4 x 63.5) mm

Size (L x W x H): with Br acket

< 8.3 x 6.55 x 2. 56(in) (211 x 166 x 65) mm

Weight:

1.7lbs (0.7 7 kg)

External Power Input Voltage:

9 VDC to 36 VDC

Antenna Power:

Temperature (ambient)

Humidity:

95% non-condensing

MIL-STD-810F, Method 510.4, Procedure I (Dus t)6h 1750 +/- 175ft/min blowing

MIL-STD-810F, Method 510.4, Procedure 2;

MIL-STD-810F, Method 506.4, Procedure I;

NCT Proprietar y Data

PVT,

NMEA-0183 Messages

ALM, GB S, GGA, GLL, GRS, GSA, GST, GSV, RMC, VTG, a n d ZD A

Code Corrections

RTCM 1 or 9; 3
Port A

RS-232 serial port, from 4800 bps to 115.2 kbps, 1PPS

Port B

RS-232/RS-422 serial port, from 4800 bps to 115.2 kbps

Port C

Power port, from 9VDC to 36VDC, 1PPS

Table 3-7: C-Nav1010 Physical and Environmental

Consumption:
Connectors:

I/O Ports:
DC Power:
GPS/L-band Antenna:
L-band Antenna:

ANT 1:
ANT 2 (C-Nav 1010R Only):

Operating

Storage:

Dust

Sand

Precipitation

<5 W

2 x 9 pin Circul ar
1 x 9 pin Circul ar
TNC-F

TNC-F (C-Nav1010R Only)

5.0 VDC, 150mA

5.0 VDC, 150mA

-30º to +70º C
(-22º to +158º F)

-40º to +85º C
(-40º to +185º F)

dust at 10.6 +/- 7g/m³ at 25°C and 70°C.

90 mins 18-29m/s blowing sand at 2. 2 +/- 0.5g/m³ from front and back.

30min of 40mph 0.5mm-4.5mm droplets front and back.

Table 3-8: C-Nav1010 I/O Messages

Raw Measurement
Satellite M essages
Nav Quality
Rec eiver Commands

PNCTSET

(O utput O nly)

WAAS, EGNOS, MSAS, GAG A N
C-Nav Corr ections Service

Table 3-9: C-Nav 10 10 C on nector Assignme nts

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C-Nav Hardware Reference Guide

Figure 3-11: C-Nav1010 Power Supply

C-Nav1010 Antennas

Table 3-10: C-Nav1010 Standard Antenna Specifications

Frequency 1525-1660 MHz

GPS L1 plus C-Nav
Polarization Right Hand Circul ar (RHCP)
Pre–Amplifier 35dB gain (+/-1.2dB)
Noise Figure <2.1dB
Filter Rejec t ion 9dB @ 1690MHz

21dB @ 1626MHz

38dB @ 1660MHz
Impedance 50 Ohms
VSWR / RL
Band Rejection 20dB @ 250MHz
RF Power Handling +30dBm (1 W)
Input Voltage 2.5 – 24 VDC
Power Consumption 0.2W

Cable Connector TNC Female
Operating Temp
Altitude 70, 000ft; 21,336m
Finish Skydrol resistant polyu rethane E namel w ith ni ckel plated ba s e
Material 6061-T6 Aluminum alloy ba se com posite ra dome, impact, abr asi on, UV, solvent,

Weight 397g (14oz)
Vibration >30g’s
Designed to FAA TSO-C144, D O -160D, D0-228, MIL-C-5541, MIL-E-5400, MIL-I-45208A, MIL-

Mount Dimensions 1”-14 thread

≤ 2.0:1 / 9.54dB min.

39mA +10mA @ 5VDC

-55°C to +85°C

skydrol resist ant, an d fir e retardant

STD-810, AND SAE J1455

Depth of 1.25”; 32mm

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C-Nav Hardware Reference Guide

Part Number

P/N: NAV82-001018-0001LF (45° - 25°)

Frequency

1525-1575 MHz
Polarization

Right Hand Circul ar (RHCP)

Pre–Amplifier

34dB gain min.

Noise Figure

2.9dB

Impedance

50 Ohms

Input Voltage

2.5 to 24 VDC

Power Consumption

0.3W typical
Connector

TNC Female

1.5”

2.3”

5”

[127mm]

[38mm]

[59mm]

Figure 3-12: C-Nav1010 Standard Antenna Dimensions

Figure 3-13: C-Nav1010 Standard Antenna Radiation Pattern

Table 3-11: C-Nav1010 L-band Antenna Specifications (45° - 25°)

INMARSAT StarFire™

60mA +10mA @ 5.0VDC

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C-Nav Hardware Reference Guide

Operating Temp

-55°C to +85°C

Finish

Sky drol resista nt polyur ethane Enamel ba se Iri diteper MIL-C-5541

Material

6061-T6 Aluminum alloy ba se com posite ra dome, impact, abr asi on, UV, solvent,
Weight

5.2oz [146g]

Vibration

>30g’s

Designed to

FAA TSO-C144, DO-160D, D0-228, MIL-C-5541, MIL-I-45208A, MIL-STD-810, AND
Wind loading

135 MPH

Ø 0.20 [5.1]

100°

Ø 3.5
[88.9]

1.344

[34.12

skydrol resistant, and fire retard ant

SAE J1455

Figure 3-14: C-Nav1010 L-band Antenna Dimensions (45° - 25°)

Figure 3-15: C-Nav1010 NAV82-001018-0001LF Antenna Mounting (45° - 25°)

Ø 0.385 [9.78]

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C-Nav Hardware Reference Guide

Magnetic attachment shear
strength

Direct attachment f orce p ull

4Kg Typi cal

The quadrafilar antenna
wind loading

200Km/hr.

Minimum break-over forc e

10Kgm

Figure 3-16: C-Nav1010 NAV82-001018-0001LF Radiation Pattern (45° - 25°)

Table 3-12: C-Nav1010 L-band Antenna Specifications (<25°)

Part Number NAV82-001003-0001LF
Frequency 1525-1585 MHz INMARSAT

StarFire™
Polarization Right Hand Circular (RHCP)
Pre–Amplifier 25dB gain min. (to coax end)
Noise Figure 1. 0dB typical
Impedance 50 Ohms
Input Voltage 3.0 to 5.5 VDC
Power Consumption 0.3W typical

8.5mA +10mA @ 3.6VDC
Cable Connector TNC Female
Cable Length 3 meters
Operating Temp

-55°C to +85°C

3Kg Typi cal

(foliage brushing)

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C-Nav Hardware Reference Guide

Figure 3-17: C-Nav1010 NAV82-001003-0 00 1LF Antenna and Mounts (<25°)

Figure 3-18: C-Nav1010 NAV82-001003-0001LF Radiation Pattern (<25°)

36

C-Nav Hardware Reference Guide

C-Nav2050

C-Nav2050 Receiver

Figure 3-19: C-Na v2050 Front View

Figure 3-20: C-Na v2050 Top View

37

C-Nav Hardware Reference Guide

ALM, GB S, GGA, GLL, GRS, GSA, GST, GSV, RMC, VTG, Z DA

Proprietary NMEA-0183

NCT Proprietary

Table 3-13: C-Nav205 0 Phy si c al a nd Environmental

Size (L x W x H): < 8.18” x 5.67” x 3.06”
Weight: <4 lbs (1.81 kg)
External Power:

Input Voltage:
Consumption:

Connectors:

I/O Ports:
DC Power:

RF Connector:
Antenna Power 5 VDC, 0.05mA bias for LNA
Temperature (ambient)

Operating

Storage:
Humidity: 95% non-condensing

NCT Proprietary Data PVT ,

NMEA-0183 Messages
(O utput O nly)

Type
(O utput O nly)

10 VDC to 30 VDC
8 W

2 x 7 pin Lem o
4 pin Lemo
TNC

-40º C to +55º C

-40º C to +85º C

Table 3-14: C-Nav2050 I/O Messages

Raw Measurement
Satellite M essages
Nav Quality
Rec eiver Commands

SET

Code Corrections RTCM 1 or 9

WAAS/EGNOS/MSAS/GAGAN

RTK Cor rection D ata (I / O )

C-Nav (RTG Dual)
RTCM 18,19 or 20, 21 CMR+ /CMR (Msg. 0, 1, 2)

Table 3-15: C-Nav2050 Connector Assignments

Data Interfaces:

2 serial ports from 1200 bps to 115.2 kbps

CAN Bus I/F C-Nav2050M Only

Even t Marker I/P C-Nav2050M Only

1PPS C-Nav2050M Only

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C-Nav Hardware Reference Guide

Figure 3-21: C-Nav2050 Power Supply

Figure 3-22: C-Nav2050 RS-232 to DP RS-422 MOXA Converter (MOXTCC-801)

• The C-Nav2050 chassis/ground is internally connected to the power ground, thus the
Isolation Mount Adaptor may be needed when using DC power to prevent ground loops.

Figure 3-23: C-Nav2050 Isolation Mount Adaptor

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C-Nav Hardware Reference Guide

C-Nav2050 Antennas

Table 3-16: C-Nav205 0 St a nd ar d Antenna

Part Standard Antenna
Part Number 8250001-0
Frequency 1525-1585 MHz, GPS L1, plus INMARSAT C-Nav Correction Service

1217-1237 MHz, GPS L2
L1 Phase Centre 58.7mm
Polarization Right Hand Circular (RHCP)
Pre–Amplifier 39dB gain (+/-2dB)
Noise Figure <2.5dB
Impedance 50 Ohms
VSWR / RL
Band Rejection 20 dB @ 250MHz
RF Power Handling 1 Watt
Input Voltage 4.2 to 15.0 VDC
Power Consumption 0.3W

Cable Connector TNC Female
Operating Temp
Altitude 70, 000ft; 21,336m
Finish Fluid resistant Ultem, UV stable

≤ 2.0:1 / 9.54 dB min.

60mA +10mA @ 5VDC

-55°C to +85°C

Table 3-17: C-Nav2050 Airborne Antenna

Part Airbor ne Ant enna
Part Number 8250001-0
Frequency 1525-1585 MHz , GPS L1, plus INMARSAT C-Nav Correction Service

1217-1237 MHz, GPS L2
L1 Phase Centre 58.7mm
Polarization Right Hand Circular (RHCP)
Pre–Amplifier 39dB gain (+/-2dB)
Noise Figure <2.5dB
Impedance 50 Ohms
VSWR / RL
Band Rejection 20 dB @ 250MHz
RF Power Handling 1 Watt
Input Voltage 4.2 to 15.0 VDC
Power Consumption 0.3W

Cable Connector TNC Female
Operating Temp
Altitude 70, 000ft; 21,336m
Finish Fluid resistant Ultem, UV stable

≤ 2.0:1 / 9.54 dB min.

60mA +10mA @ 5VDC

-55°C to +85°C

40

C-Nav Hardware Reference Guide

• To achieve the greatest level of accuracy, the absolute phase center values must be
incorporated into your processing. Phase center information on this antenna is found
on the anten na bottom, and in the figure below.

Figure 3-24: C-Nav2050 Standard Antenna Phase Center Dimensions

Figure 3-25: C-Nav2050 Antenna Dimensions [inches (mm)]

Figure 3-26: C-Nav2050 Airborne Antenna Dimensions

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C-Nav Hardware Reference Guide

Figure 3-27: C-Nav2050 Standard & Airborne Antenna Radiation Patterns

• Optimal an t e nn a performance is re ali z e d at el ev a tions greater than 30º.

• There is a 10dB variation between 0º and 90º elevation (factor 10x); therefore, lower

elevation satellites are always more difficult to track.

• There is a 5dB variation between ~35º and 0º elevation (factor >3x)

Figure 3-28: C-Nav2050 Antenna Mounting Pole Adaptor Dimensions

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C-Nav Hardware Reference Guide

Magnetic attachment
shear strength

Direct atta c hment force

4Kg Typi cal

The quadrafilar antenna

200Km/hr.

Minimum break-over forc e
(foliage brushing)

10Kgm

Table 3-18: C-Nav2050R Antenna

Part L-band C-Nav2050R Antenna
Part Number 825R003-0
Frequency 1525-1576 MHz

INMARSAT

C-Nav Correct ion S ervice
Polarization Right Hand Circul ar (RHCP)
Pre–Amplifier 25dB gain min. (to coax end)
Noise Figure 1.0dB typical
Impedance 50 Ohms
Input Voltage 3.0 to 5.5 VDC
Power Consumption 0.3W typical

8.5mA +10mA @ 3.6VDC
Cable Connector TNC Female
Cable Length 3 meters
Operating Temp

-40°C to +85°C

3Kg Typi cal

pull

wind loading

Figure 3-29: C-Nav2050R Antenna Dimensions and Mounts

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C-Nav Hardware Reference Guide

Figure 3-30: C-Nav2050R Antenna Radiation Pattern

Figure 3-31: C-Nav2050R An te nna LNA Wid e-band Respo nse

• Optimal an t e nn a performance is realized at elevations between 10º and 50º.

• There is an 8dB variation between 40º and 90º elevation ( fact or 6. 3x ) ; therefore,

higher elevation satellites are always more difficult to track.

• There is a 3dB variation between 10º and 0º elevation (factor >2x)

44

C-Nav Hardware Reference Guide

C-Nav1000

C-Nav1000 Receiver

Figure 3-32: C-Nav1000 Receiver Front View (mm)

Figure 3-33: C-Nav1000 Receiver Top View (mm)

Figure 3-34: C-Nav1000 Receiver Clearance Area

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C-Nav Hardware Reference Guide

Figure 3-35: C-Nav1000 RS-422 to DP RS-232 MOXA Converter (MOXTCC-801)

C-Nav1000 Display

Figure 3-36: C-Nav1000 Display Front View (mm)

Figure 3-37: C-Nav1000 Display Top View (mm)

46

C-Nav Hardware Reference Guide

C-Nav1000 Antennas

Beacon Receiver Specifications

Beacon Frequency Range 283.5 - 325.0 kHz
Beacon LNA Gain 34 dB

L- band Receiver Specifications

L- band F r equenc y Range N/ A
L- band LNA Gain N/ A

Power Input Specifications

Input Volt ag e 4.0 - 13 VDC
Input Current 50 - 60 mA

Mechanical Specifications

Enclosure PVC plastic
Dimensions 128 mm square x 84 mm high

5.06" square x 3.33" high)
Weight 450 g (1.0 lb)
Mounting Thread 1- 14- UNS- 2B
Connector TNC- S

Environmental Specifications

Storage Temperature -40° C to +80° C
Operating Temperature -30° C to +70° C
Humidity 100% condensing

Figure 3-39: MGL-3 Antenna and Mou nting Pole

Figure 3-38: MGL-4 (H-field) Antenna

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C-Nav Hardware Reference Guide

C-Nav1000 Display Mounting Options

Gimbal Mount

Figure 3-40: Gimbal Mo unt Clearance Area

Panel Mount

Figure 3-41: Panel Mount Frame Dimensions (mm)

Figure 3-42: Clearance Distance Behind the Display (Panel Mount)

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C-Nav Hardware Reference Guide

Figure 3-43: Panel Mount Hole Dimensions (mm)

Figure 3-44: Panel Mounting C-Nav1000 Display

Figure 3-45: C-Nav1000 Display Panel Mounted

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C-Nav Hardware Reference Guide

IALA GPS System

IALA Receiver (MBX-3S, MBX-4)

Operational Specifica ti o ns:

Operational SpecificationItem Specification

Frequency Range 283.5 - 325 kHz
Channels 2
Input Sens it i vi ty 2.5 μV/m for 10 dB SNR
@ 100 bps MSK Rate
Acquisition Time < 1 Second Typical
MSK Bit Rate 100, 200, or Autom ati c
Frequency Selection Manual or Automatic
Frequency Offset ± 5 Hz
Dynamic Range 100 dB
Adjacent Channel Rejection 60 dB @ f0 ± 500 Hz
Decoding RTCM 6/8
Demodulation MSK

ial Interface Specifications
Item Specification

Interface Levels RS-232C and RS-422
Data Connector DB9 Socket
Data Port Baud Rate 2400, 4800, or 9600 Baud
Data Output Form at RTCM SC-104, NMEA 0183
Data Input Protocol NMEA 0183

Power Specifications
Item Specification

Input Volt ag e 9-40 VDC
Input Current 210 mA @ 12 VDC
Power Consumption 2.5 W
Power Connector Circula r 2-pin Locki ng Plug

Mechanical Characteristics
Item Specification

Display 2-line, 16-c haracter LCD
Keypad 3-switch membrane
Enclosure Extruded Aluminum with Aluminum

Front and Bac k Plates.

Length 150 mm (5.9“)
Width 125 mm (4.9”)
Height 51 mm (2.0 ”)
Weight 0.64 kg (1.4 lb)
Antenna Connector BNC Socket
Optional Signal Output Connector TNC Socketnvironmentcifications
Storage Temperature -40°C to 80°C
Operating Temperature -30°C to 70°C
Humidity 95% Non-Condensing

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C-Nav Hardware Reference Guide

Figure 3-46: MBX-4 Receiver with Mounting Bracket (Top Mounted)

Figure 3-47: Bottom-view M BX-4 With Mounting Bracket (Bottom Mounted)

Figure 3-48: IALA Receiver Mounting Bracket Dimensions

51

C-Nav Hardware Reference Guide

IALA Whip Antenna Dimensions

This antenna, referred to as an E-field whip antenna, is sensitive to the
electrical field of contained in the base of the MBA-3, which together
amplify signals in the 283.5 to 325.0 kHz frequency band.

The MBA-3 is compatible with standard marine threaded mounts (1-14­UNS), and must be grounded for optimum performance. The MBA-3
antenna is constructed with a nylon base and a fiberglass whip antenna.

Item Specificat ion

Frequency Range 283.5 - 325 kHz
Gain 20 dB
Pre-Amplifier Integral Low Noise Amplifier

Power Specifications
Item Specification

Input Volt ag e 10-14 VDC supplied by receiver
Input Current 10 mA

Mechanical Characteristics
Item Specification

Enclosure Fibergl as s an d t hr e ad ed ny l o n
Mounting Thread 1-14-UNS-2B

Length 371 mm (14.6”)
Diameter 39 mm (1.5”)
Weight 176 g (0.39 lb)
Ground Wire Length 1.3 m (51. 0”)
Antenna Cable Pig Tail 297 mm (11.0"), or 3.0 m (10')
Antenna Connector BNC-S
Antenna Extension Cable RG-58U, < 150 m (450 ft) in Length

Environmental Specifications
Item Specification

Storage Temperature -40°C to 80°C
Operating Temperature -30°C to 70°C
Humidity 100% Condensing

Operationa l Specifications

52

C-Nav Hardware Reference Guide

C-NaviGat or II

C-NaviGator II Control and Display Unit

Figure 3-49: C-NaviGator II Display (Front View)

Figure 3-50: C-NaviGator II Side-panel Connectors

Figure 3-51: C-NaviGator II Power Supply

53

C-Nav Hardware Reference Guide

Mechanical Specifications

Size (L x W x H) 82.2mm (3.2”) x 340 mm (13.4”) x 260mm (10.2”)
Weight 4.8 kg (10.6 lbs)
Display 10.4” TFT LCD, 1024x768, 400 nit, Resistive TS
CPU 1.0 GHz VIA 7C, 512 MB, 2GB CF

Power Input Specifications

Input Volt ag e 12 VDC +/- 5 % (24-12VDC converter available)
Consumption 30 W

Power Supply

Size (L x W x H) 31mm (1.2”) x 110mm (4.3”) x 62mm (2.4”)
Connector Conxall, Micro-Con-X 16282-2SG-311
Input Volt ag e 90 – 264 VAC
Power 60 W
Frequency 47 - 63 Hz
Output Voltage 12 VDC (+/- 5%)
Operating Temperature 0º C ~ +40º C
Storage Temperature -20º C ~ +65º C
Humidity Operating: 20 ~ 80% RH; Storage: 10 ~ 90% RH

Connectors

DC Power Conxall, Micro-Con-X 17282 -2PG-300
I/O Ports 4 x 9 pin RS-232 DBM (RS232-422 converter available)
Keyboard/Mouse PS/2
LAN 1 x 100/1000 Mbps
USB 2 x 2.0
VGA 1 x 15 pin DBF
Printer, Parallel 1 x 25 pin DBF

Environmental Specifications

Operating Temperature 0º C to +60º C
Storage Temperature -20º C to +85º C
Humidity 5 - 90% @ 60º C, no n-condensing

54

C-Nav Hardware Reference Guide

C-NaviGator II Mounting Options

Option #1: Allows mo un ti n g from c ei li ng, wall or desk to p wi t h ful l y adjustable positi oning.

Figure 3-52: RAM 100 75 VESA Base (w / Steel Reinforce) / RAM-D-246U-IN1

This piece fits to the standard VESA mounting holes on the back of the C-NaviGator.

Figure 3-53: RAM Double Socket Arms

RAM-D-201U-C / RAM Double Socket Arm SHORT (3.63”)

RAM-D-201U / RAM Double Socket Arm MEDIUM (6.88”)

RAM-D-201U-E / RAM Double Socket Arm LONG (11.75”)

Choose from one of the arms above. We recommend the medium length.

Figure 3-54: RAM 11" X 3" Base (w/ Steel Reinforce) / RAM-D-111B-IN1U (left) &

RAM 3.68 DIA. BASE (w/ Steel Reinf orce) / RAM-D-202U-IN1 (right)

This piece is fixed to the ceiling, counter top or wall.

55

C-Nav Hardware Reference Guide

Option #2: Desktop Stand

Figure 3-55: Flat Screen Table Stand (for C-NaviGator II) / CHIFSB018BLK

Option #3: Wall Mount

Figure 3-56: T ilting VESA Wall Mount (for C-NaviGator II) / PEEST630

56

C-Nav Hardware Reference Guide

Option #4: Front Panel Mount

Use this adaptor if unable to secure display from the back. Appropriate hardware is included to

secure the C-NaviGator to the Front Panel Mount prior to mounting. Bolt thread size is M4 x

6mm

Figure 3-57: Front Mount Kit (for C-Nav iGator II) / SYNIW O-6710-7CRBR2

57

C-Nav Hardware Reference Guide

Option #5: 19” Rack Mount

Use this adaptor if installing the C-NaviGator to a rack. The 19” Rack M ou nt takes up 7U of rack
space and is 12 ¼” in height. Appropriate hardware is included to secure the C-NaviGator to th e

Rack Mount prior to mounting. Bolt tread size is M4 x 6mm

Figure 3-58: 19” Mounting Kit (for C-NaviGator II) / SYNIW O-6710-7CBR9

58

C-Nav Hardware Reference Guide

Figure 3-59: C-NaviGator II (side USB-port model) Outline Diagram (mm)

Both inside and outside mounting holes on vesa mount are M4 x 16mm in size.

Inside holes have 75mm spacing

Outside holes have 100mm sp aci ng

59

C-Nav Hardware Reference Guide

Figure 3-60: C-NaviGator II Cut-out Diagram (mm)

Cut-out Panel includes hardware to facilitate bolting of the C-NaviGator from the rear via M4 x

16mm sized bolts (6 places) or from the front via M4 or #10 sized bolts (4 places, rev. A only)

60

C-Nav Hardware Reference Guide

Figure 3-61: C-NaviGator II rev. A (front USB-port model) Outline Diagram (mm)

61

C-Nav Hardware Reference Guide

C-NaviGator II LCD Touch-screen Care and Cleaning

LCD screens are not like ordinary monitor screens in that they are not made of glass, rather
they are ma de up of a so ft fil m that can easil y be dam a ge d by abr asi ve cloth or pa per , chl or i d e
and other chemicals found in ordinary tap water. LCD screens are delicate and they must be
handled with the utmost care.

Care and Cl ean i ng Tips:

• Turn off display before clea ning.

• Use a commercial cleaner specially designed for LCD displays, such as Klear Screen

www.klearscreen.com (P/N: IK-8/MK-COM). If a commercial cleaner is unavailable, use

distilled water as tap water may leave mineral spots. Eyeglass cleaner can also be used
if absolutely necessary, however it may contain some alcohol, which could dry out the
screen and cause it to go cloudy.

• Use a soft, lint-free, anti-static cloth such as eyeglass cloths, Microfiber cloth, Chamois,
or a clean cotton T-shirt. Dampen cleaning cloth with your solution and apply very gentle
pressure using a circular motion.

• Ensure screen is thoroughly dry before powering on.

Do not:

• Spray cleaner directly on screen. It could possibly leak inside a non-sealed unit and
cause damage.

• Use solution that contains ammonia (e.g. Windex). It can etch the screen surface and
cause the plastic to go cloudy.

• Use paper towels, tissues, dish cloths. Paper products contain micro-particles o f woo d
and will cause tiny scratches that you may not see, but will be harmful.

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C-Nav Hardware Reference Guide

Chapter 4 ................................................... Hardware Accessories

Huber + Suhner Lightning Protectors

Model No. 3403.17.0045 Specifications

63

C-Nav Hardware Reference Guide

Model No. 3403.17.0045 Dimensions

Figure 4-1: Huber + Suhner Model No. 3403.17.0045

64

C-Nav Hardware Reference Guide

Model No. 3402.17.0070 Specifications

65

C-Nav Hardware Reference Guide

Model No. 3402.17.0070 Dimensions

Figure 4-2: Huber + Suhner Model No. 3402.17.0070

66

C-Nav Hardware Reference Guide

Huber + Suhner Lightning Protector Mounting Instructions

67

C-Nav Hardware Reference Guide

68

C-Nav Hardware Reference Guide

MOXA Converters

TCC-80I

TCC-80I Specifications

69

C-Nav Hardware Reference Guide

TCC-80I Dimensions

Figure 4-3: Moxa TCC-80I Converter Dimensions

TCC-82

70

C-Nav Hardware Reference Guide

TCC-82 Specifications

TCC-82 Dimensions

Figure 4-4: TC C-82 Converter Dimensions

71

C-Nav Hardware Reference Guide

Times-Microwave LMR 40 0 Coa xial C a ble

LMR400 Specifications

72

C-Nav Hardware Reference Guide

Figure 4-5: LMR400 Attenuation vs. Frequency Graph

LMR400 Connectors

Figure 4-6: LMR400 Connectors

73

C-Nav Hardware Reference Guide

74

C-Nav Hardware Reference Guide

Chapter 5 ...................... Technical Referenc e and Interface Gui de

Coaxial Cable

Terminating Coaxial Cable (Times Microwave Systems)

1. Flush cut the cable squarely

Figure 5-1: Components for Termination of Coaxial Cable

2. Slide the heat shr i nk bo ot over the end of the c able, followed by the ferr ule. Slide
the first end of the prep/strip tool over the end of the cable and rotate it
clockwise. Spin the tool until it spins freely. Remove the tool and any residual
plastic from the center conductor by rotating a knife around the circumference of
the center conductor at the face of the core.

Figure 5-2: Prep/Strip Tool (large end)

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C-Nav Hardware Reference Guide

3. Debur the center conductor using a deburring tool or a file.

Figure 5-3: Duburring Tool

4. Insert the cable into the opposite end of the prep/strip tool and rotate clockwise
until the tool spins freely. Remove the tool (If you are using a knife to complete
this step, be careful not to nick th e br ai ds ) .

Figure 5-4: Prep/Strip Tool (smaller end)

76

C-Nav Hardware Reference Guide

5. Apply a small amount of RMA flux around the exposed center conductor.

Figure 5-5: RMA Flux Application

6. Place a piece of solder into the pin until it bottoms. Trim the solder flush with the
back of the pin with a knife. Place a shim over the cable and up against the core
(a razor blade will do). Now place the pin over the center conductor and heat the
base of the pin with a soldering iron while monitoring the weep hole in the pin.
Remove the heat when you have seen the solder has flowed and wetted
properly.

Figure 5-6: Soldering

77

C-Nav Hardware Reference Guide

7. Remove the shim and slide the connector over the pin. Once the connector has
been pushed all the way on so that the connector bottoms out onto the core,
slide the ferrule over the braid, making an impression in the braid at the point that
it protrudes between the ferrule and the connector. Trim the braid at this
impression with scissors.

Figure 5-7: Connector I ns t all ation

8. Make sure that the connector is bottomed. Bring the ferrule all the way up to the
back of the connector. Check the pin height with a pin gauge. Crimp the ferrule
close to the connector with a crimping tool. DO NOT CRIMP TWICE. A second
crimp further back on the ferrule will end up compressing the core and cause
degradation of performance. Slide the boot up to the back of the coupling nut and
shrink with a heat gun until a lip of adhesive can be seen at both ends of the
boot.

Figure 5-8: Ferru le Crimping

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Coax-Seal® Weather Sealant Installation

1. Shown below is a short pigtail of RG-59U coax cable terminated in a Snap and
Seal "F" connector which is then joined to a female-female adapter or barrel
connector.

Figure 5-9: RG-59U Coaxial Cable

2. The next few photos will show how this barrel connector is used in a splice and
how it is waterproofed for marine use.

Figure 5-10: Coaxial cable with Barrel Connector

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3. The second cable with connector is attached to the barrel adapter and was
tightened. The connector on the right has an O ring and is sealed to the coax
internally with silic one grease.

Figure 5-11: Coax-seal Roll

4. Coax-Seal is a putty like material in tape form. The white waxed
paper keeps it from sticking to its self.

Figure 5-12: Coax-seal Application

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5. Note that the first wrap comes back on itself exactly and the second run starts
the diagonal wrap. Wrap from the coax cover toward the fitting with one half
overlap with each winding. The last wrap again comes straight back over the
previous wrap without a diagonal. The seal is slightly sticky and should be
molded now by hand to remove any gaps and to ensur e that all the wraps are
blending together.

Figure 5-13: Coa xial Cable Fully Sealed

6. At some point the wrap will almost fuse together and the material may have to be
cut away from the cable.

Figure 5-14: Coax-seal Cross-section

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PACKAGING:

•

60” consumer rolls, 3/32" thick x 1/2" wide, in retail packaging for

DESCRIPTION:

Easily appli ed, hand-moldable, tacky black plastic mastic, on peel-away paper

APPLICATIONS:

Provides a long-lasting, waterproof seal for coaxial c able fittings and many other
VISCOSITY:

ASTM D5-52, gm load, 5 sec.=7.0/10.0 mm. Non-hardening, non-oxidizing at
TEMPERATURE RANGE:

Apply between 40° F. to 110° F.

PERCENT SOLIDS:

98%

SOLVENTS:

None

OTHER PROPERT I ES:

Material is non-staining t o paint; stay s flex ible and maintains a waterproof seal

OPTIMUM CURE CYCLE:

Not curable

APPLICATION

Hand applied

Table 4-1: Coax-Seal Product Specifications

COAX-SEAL PRODUCT SPECIFICATIONS

pegboard or counter di spl ay .

• 12’ industrial rolls, 3/32" thick x 1/2" wide or 1” wide.

• Pre-cut st rips, 3/32" thick x 1/2" wide, in 10” and 4” lengths, bulk-packed.

• 10” stri p or (2) 4” strips in envelope, with c om plete instructions for use.

backing, suitable for waterproofing a wide variety of connections. Adheres to
vinyl and PVC outer jack ets. Product is non-conductive, non-cont ami nating and
non-toxic, and UV-stable.

connections. Use for TV and radio antennas, satellit e dishes, CAT V , wireless
networks, marine elec tronics, feed lines, radar and microwave installations, and
many other applic ations.

ambient temperature.

over an extreme range of t em per atures. Will not crack at -200° F, will not slump
1 hr. @350° F.

EQUIPMENT:

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Chapter 6 ........................................................................ Glossary

Troubleshooting

The followi n g i n form ation is provided for t h e use and operation of C-Nav DGNS S Systems. It is
recommended that you read through this chapter before calling C-N av Support. Refer to p. 2 for
C-Nav 24/7 support contact information. You can also visit www.cnavgnss.com/faq for a list of
Technical Support an d Product-relat ed fre quently asked qu esti o ns .

Up-to-date information on all C-Nav Products can be found at www.cnavgnss.com/products

Increasing GNSS Accuracy

C-Nav GNSS receivers will give the most accurate position with a C-Nav corrections
subscription. These corrections are Real Time Gypsy (RTG) which are global in coverage. The
system can also decode SBAS type system corrections as a fall back measure. By control of the
various GNSS parameter settings, optimal GNSS satellite configurations are maintained,
preventing less accurate positions from being computed. However, these parameters can
prevent reliable positions from being output as well. If your GNSS application can tolerate
occasional outages, then more accuracy is possible by changing the various GNSS receiver
parameter s fr om thei r de fault values.

The receiver must have sufficient satellites and signal from either SBAS (WAAS/ EGNOS) or C­Nav Subscription Service sources to achieve a dv e r ti s ed acc uracies. The geom etr y al s o pl ays
an important role in navigation, meaning that the GNSS signals received must have good
dispersion. This dispers ion reduc es error s by prov i ding wide angles for tril at eration algorit hm s to
more accurately compute position.

GNSS receiver parameters that affect accuracy are:

• Elevation Mask - Raising this mask prevents the receiver from using some low
elevation satellites, often a source of inaccurate positions.

• Dilution of Precision (DOP) Mask - Decreasing the DOP mask prevents GNSS
satellites of poor geometr y from c o ntr i bu ti n g t o in a cc ur at e pos i tions.

• GNSS Mode - Three-dimensional positions are more accurate than two-dimensional

positions, so changing the receiver to Manual 3D prevents 2D positions from being
computed.

Local conditions may have an impact on accuracy. Interference, such as harmonics from co­located transmitting antennas, and multipath, induced by reflective surfaces in the proximity of
the antenn a, ca n be har mful to the quality o f the measurements used within navigation. A
relatively uncontrolled source of position inaccuracy is multipath noise, caused by reflections of
the GNSS signals from nearby structures, buildings and flat surfaces. For best accuracy, mount
the GNSS antenna so it has a clear view of the sky. Accuracy is best when operating away from
structures. The same problem of masking can also occur in the reception of C-Nav Sig nals fr om
the ge o-stationary communication satellites. The user must take care to ensure that a clear and
unobstructed view of the sky is maintained for C-Nav GNSS Ante nn ae, and that no RF
interfer ence sources are pres e nt.

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Intermittent GPS Loss

When GNSS lock is intermittent, the antenna cable may be disconnected or loose. Check that
all connections are secured properly. Protect the cable/antenna connection with a weather­sealant ta pe such as Co ax-seal. If the sealant tape is not properly placed, water may enter the
cable connection and cause intermittent loss of power or data communication link.

If the antenna is connected properly, ensure that it is mounted on the highest point so that no
GNSS sign al s ar e bl ocked. Dependin g on the lo cation of the C-Nav GNSS antenna, the
satellites and possible obstructions, one or more satellites may be blocked. The C-Nav GNSS
receiver must be mounted so that it has a clear view of the sky. It should be on the center-line of
the vessel , an d aw ay fr om any s our ces of interfer ence such as el ect ri c m otor s, radar ant en nas,
L-band communication antennas, cellular radio telephone antennas, radio voice or data
communication towers or satcom domes. If the C-Nav GNSS antenna location seems fine,
check the GNSS configuration parameters. If they are set to extreme levels, the C-Nav GNSS
receiver could ignore valid satellite data.

Power Lines and Strong Magnetic Fields

In North America, the energy from electrical power lines is 60 Hz (50 Hz in Europe). The
harmonic energy falls off rapidly as the frequency increases. Thus, power lines have very little
effect on the GNSS signal . However, noise radiation from power lines may cause interference to
the GNSS and L-Band signal corrections. The interference, if any, is usually localized, up to a
half mile from the power line.

Whil e strong magnetic fields have no effect on GNSS signals, some computers and other
electronic equipment radiate electromagnetic energy that can interfere with C-Nav GNSS
antennas or with the corrections data link. If you suspect interference from a local magnetic
field, move the C-Nav GNSS receiver away from any electronics while observing the C-Nav
GNSS receiver’s output.

Checking for Cable Failure

To check a C-Nav GNSS receiver’s interconnect cable for a short, use an ohmmeter. The
resista nc e o f a good cable be tw e en any of the conductors is infinite and the resistance between
each end of the same conductor is near zero. If the interconnect cable is defective, contact C­Nav Support.

C-Nav Corrections Availability

Radio signals from geo-stationary communication satellites that broadcast the C-Nav signals
occasionally get blocked or encounter interference. If you are outside of the range of these
broadcasts or have local RF interference from power lines or high power radio transmitters, you
may not receive the C-Nav corrections. High voltage power lines can be a severe source of
noise, particularly if there is a leaky insulator or other source of corona discharge.

The ionosphere can also cause loss of signal especially along the geomagnetic equator of the
earth. The 11-year solar cycle can interfere with L-band transmitted correction signals, as can
instances where the sun is directly in line with the view of a geo-stationary communications
satellite. Often, simply s el ecting another L-band communication satellite will resolve the
reception of the C-Nav correc ti o ns f or the per i o d o f th e ionospheric distur b an c e.

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Loss of Settings When the Unit is Powered Off

C-Nav GNSS Receiver configuration parameter settings are stored in battery-backed RAM
(random access memory). The internal lithium battery has a 10-year life span. You can assume
the Lithium battery has failed when the receiver no longer retains configuration parameter
setting changes. Contact C-Nav Supp or t for replacement lithium batteries.

All C-Nav proprietary software (C-Monitor, C-Setup) will retain any port configuration
parameters and GNSS configuration information when the power is turned off or removed.

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Abbreviations

1PPS - 1 Pulse Per Second
2dRMS – Twice the distance Root Mean Square
A/S – Antispoofing
APC – Antenna Phase Center
BER - Bit E rror Rate
bps – bits per second
BSW – British Standard Whi twor th
C/A – Coarse/Acquisition
CEP – Circular Error Probable
CDU – Control Display Unit
COM – Communication
CMR - Compact Measurement Record
Db - Decibel
DCE – Data Comm unications Equi pment
Deg - Degree
DGPS – Differential Global Positioning System
DOP – Dilution of Precision
DTE – Data Terminal Eq ui pment
ECDIS – Electronic Chart Display & Information System
ECEF – Earth Centered, Earth Fixed
EGNOS – European Geostationary Navigation Overlay Service
FCC – Federal Communications Commission (U.S.)
GAGAN - GPS Aided Geo Augmented Navigation
GDOP – Geometr i c Dil ution of Precision
GIS – Geogra phi c I n for m ation System
GMT – Greenwich Mean Time
GNSS – Global Navigation Satellite System
GPS – Global Positioning System
HDOP – Horizontal Dilution of Precision
HF – High Frequency
HOW – Hand Over Word
Hz – Hertz
I/O – Input/Output

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IGN - Ignition
IMO – International Maritime Organization
INMARSAT – International Maritime Satellite Consortium, Ltd.
INS – Inertial Navigation System
IODC – Issue of Data, Clock
ITRF – International Terrestrial Reference Frame
JPL – Jet Propulsion Laboratory
Kbps – Kilobits per second
KHz - Kilohertz
LAN - Local Area Network
Lat – Latitude
LCD - Liquid Crystal Display
LED – Light Emitting Diode
LES – Land Earth Sta ti on
LF – Low Frequency
Long – Longitude
LORAN – Long Range Navigation System
LNA - Low Noise Ampl ifier
MSAS- MTSAT Satellite-based Au gm entation System
MSL – Mean Sea Level
NAD27 – North Americ a n Da tum 19 27
NAD83 – North Americ a n Da tum 19 83
NASA – National Aer o nautics and Space Admi ni s tr ation
Nav – Navigation
NGS – National Geodetic Survey
NOAA – National Oce anic an d At m os pheric Administr ation (U.S.)
P/N – Part Number
PCM – Pulse Code Modulation
PDOP – Positional Dilution of Precision
PPS – Precise Positioning Service
prn – pseudorandom noise
PVT – Position, Ve locit y , Time
RAIM – Receiver Autonomous Integrity Monitoring
RHCP – Right-hand Circul ar Polarization

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RINEX – Receiver Independent Exchange
RMS – Root Mean Square
RTCM - Radio Technical Commission for Maritime Services
RTG – Real-time Gypsy
RTK – Real-time Kinem ati c
S/A – Selective Availability
SBAS – Satellite Based Augmentation System
SEP – Spherical Er r or Pro ba bl e
SI – International System of Units
SNR – Signal-to-Noise Ratio
SPS – Standard P osi tioning Servic e
SSR – Spread Spectrum Radio
SV – Space Vehicl e
TDOP – Time Dilution of Precision
UHF – Ultra High Frequency
USB - Universal Ser i al B us
USGS – U.S. Geological Survey
UTC – Universal Time Coordinated
VDOP – Vertical Dilution of Precision
VHF – Very H igh Frequency
WAAS – W ide Area Augmentation System
WADGPS – Wide Area Differential Global Positioning System
WDOP – Weighted Dilution of Precision
WGS84 – World Geodetic System 1984

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Definitions

1 Pulse Per Second (1PPS) is a precis ion electronic pulse output (at TTL levels) from the GPS
receiver that marks exact second intervals. It is used for precise timing and to synchronize
sensors and acquisition computers.

.yym files see meteorol ogical files (where yy = two digit year data was collected).
.yyn files see navigation files (where yy = two digit year data was collected
.yyo files see observation files (where yy = two digit year data was collected).
Absolute Positioning is the ability of a GPS receiver to produce positional values without

another receiver for reference.
Accuracy is the degree of conformity of a measured or calculated quantity to a standard or true

value. Accuracy is therefore related to the quality of the results.
Almanac i s found in subframe 5 of the Navigation Message. It is a data fil e th at helps the

receiver track, and lock-on to satellites as it contains a summary of orbital parameters for all
GPS satellites. The almanac can be acquired from any GPS satellite.

Altitude is the vertical distance above the ellipsoid or geoid. It is always stored as height above
ellipsoid in the GPS receiver but can be displayed as height above ellipsoid (HAE) or hei gh t
above mean sea level (MSL).

Ambiguity is the unknown number of whole carrier wavelengths between satellite and receiver.
Antenna is a device used to collect and amplify the electromagnetic GPS signals broadcast by

a satellite. These electromagnetic waves are then converted into electrical currents that are
decoded by the receiver. Patch, or Microstrip antennas are most commonly used in GPS.

Antenna Phase Center (APC) is the point in an antenna where the GPS signal from the
satellites is received. The height above ground of the APC must be measured accurately to
ensure accurate GPS readings. The APC height can be calculated by adding the height to an
easily measured point, such as the base of the antenna mount, to the known distance between
this point and the APC.

Antispoofing (A/S) is an encryption technique developed by the US Department of Defense
(DoD) that when implemented, deni es acc es s to the P-C od e by any un au thorized users. Wit h
Antispoofing on, the user will need a DoD issued “key” in order to gain access to the P -Code.

Apogee is the point in the orbit of a satellite about the earth that is the greatest distance from
the center of the earth.

Autocorrelation in reference to code is a plot of the scalar product of the noise sequence with
a delayed copy of itself.

Autonomous positioning (GPS) is a mode of operation in which a GPS receiver computes
position fixes in real time from satellite data alone, without reference to data supplied by a
reference station or orbital clock corrections. Autonomous positioning is typically the least
precise positioning procedure a GPS receiver can perform, yielding position fixes that are
precise to 100 meters with Selective Availability on, and 30 meters with S/A off.

Average Deviation is a measure of variability in a data set but it is more robust than standard
deviation. It is not related to the bell-shaped curve. It is the average of the absolut e dev iations
of the values from the mean. The data values are subtracted from the mean producing a list of

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deviations from the mean. The deviations are not squared like they are for the standard
deviation; the absolute values of the deviations are used.

Azimuth the azimuth of a line is its direction as given by the angle between the meridian and
the line measured in a clockwise direction from the north branch of the meridian.

Bad Packets refer to the number of bad C-Nav Corrections Service packets received since the
unit was turned on.

Bandwidth is a measure of the width of the frequency spectrum of a signal expressed in Hertz.
Baseline is the resultant three-dimensional vector (V) between any two stations from which

simultaneous GPS data have been collected and proc essed. Generally gi ve n in ear th-centered
Cartesian coordinates where: V=(Δx, Δy, Δz)

Base station see reference station.
Baud Rate (bits per second) is the number of bits sent or received each second. For example,

a baud rate of 9600 means there is a da t a fl ow o f 9600 bi ts each seco nd . One character roughly
equals 10 bits.

Beat Frequency is either of the two additional frequencies obtained when two signals of two
freque nci es ar e mixed, equal to the sum or di ffer e nc e o f th e or igi nal frequencies .

Binary Biphase Modulation is a phase change on a constant frequency carrier of either 0 or
180 degrees. These represent the binary digits 0 and 1, respectively.

Binary Code is a system used in communication where selected strings of 0’s and 1’s are
assigned definite meanings.

Binary Pulse Code Modulation is a two-state phase modulation using a strin g o f bin ar y
numbers or codes. The coding is generally represented by 1 and 0 with definite meanings
attach ed to eac h.

Bits per second see baud rate.
Broadcast Ephemeris is the ephemeris broadcast by the GPS satellites.
British Standard Whitworth (BSW) is a type of coarse screw thread. A 5/8” diameter BSW is

the standard mount for survey instruments. (1” Mount included).

C/A code see Coarse Acquisition code.
CAN BUS is a balanced (differential) 2-wire interface that uses an asynchronous transmission

scheme. Often used for communications in vehicular applications.
Carrier is a high-frequency radio wave having at least one characteristic (frequency, amplitude,

or phase), which may be varied by modulation from an accepted value. In general, the carrier
wavelength is much shorter than the wavelength of the codes.

Carrier Beat Phase is the difference between the phase of the incoming Doppler shifted
satellite carrier signal and the phase of the nominally constant reference frequency generated in
the receiver.

Channel a channel of a GPS receiver consists of the circuitry necessary to receive the signal
for a single GPS satellite.

Chip a. The minimum transition time interval for individual bits of either a 0 or 1 in a binary pulse
code usually transmitted in a pseudo-random sequence. b. A tiny square piec e o f thin
semiconductor material on which an integrated circuit is formed or is to be formed.

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Circular Error Probable (CEP) is a measurement of precision using standard deviation that is
applicable in horizontal stations. Probability for CEP is 50%, meaning that if 100 observations
are made, half of them will be within the circular error probable with
Radius = 0.5887 (ơx + ơy)

Civilian code see Coarse Acquisition code.
Clock Bias is the difference betwee n GPS Time and UTC.
Coarse Acquisition code (C/A or Civilian code) is the pseudo-random code ge ner a ted by

GPS satellites. It is intended for civilian use and the accuracy of readings using this code can be
degraded if selective ava ilab ility (S/A) is introduced by the US Department of Defense.

Collimate is to physically align a survey target or antenna over a mark.
COM is the shortened form of the word Communications. Indicates a data communications port

to/from the GPS sensor to a controller or data collection device.
Compact Measurement Record (CMR/CMR+) is a standard format for DGPS corrections used

to transmi t cor r ec tions from a refe r ence station to rover sensors. See Related Standards in
Notices.

Controller is a device consisting of hardware and software used to communicate and
manipulate the I/O functions of the GPS sensor.

Control Point is a point to which coordinates have been assigned. These coordinates can then
be held fix ed an d ar e used in oth er dep en dant sur v eys .

Control Segment is a worldwide network of GP S m oni tor ing and control stat ions that ensure
the accuracy of the GPS satellite orbits and operation of their atomic clocks. The original control
segment consists of control facilities in Diego Garcia, Ascension Island, Kwajalein, and Hawaii,
with a master control station at the Consolidated Space Operations Center (CSPOC) at
Colora do Spr i n gs , C olor ado.

Convergence Period (C-Nav) is the time necessary for the received C-N av s i gn al cor r ec ti o ns
to be applie d and the position filtered to op ti m al performance. The convergence period is
typically 30 to 45 minutes to achieve decimeter accuracy.

Cycle Amb igu i ty see Ambiguity.
Cycle Slip is a discontinuity in measured carrier beat phase resulting from a temporary loss of

lock in the carrier-tracking loop of a GPS receiver .
Datum A reference datum is a known and constant surface, which can be used to describe the

locati on o f unk n ow n points. Geodetic da tum s de fi ne the size and s h ap e of the ear t h and the
origin an d or i ent ati o n of the coordinate systems u sed t o map the eart h.

DB9P a type of electrical connector containing 9 contacts. The P indicates a plug pin (male).
DB9S a type of electrical connector containing 9 contacts. The S indicates a slot pin (female).
DCE Data Comm uni cations Equipment. Defined pin assignments based on the IEEE RS-232

signaling standard. See Figure 6-1:

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C-Nav Hardware Reference Guide

Figure 6-1: DTE to DCE RS-232 Pin Assi gnments

Deflection of the Vertical is the angle between the perpendicular to the geoid (plumb line) and
the perpendicular to the ellipsoid.

DGPS see Differe ntial GPS.
Differencing is a technique used in baseline processing to resolve the integer cycle ambiguity

and to reduce a number of error sources including oscillator variations and atmospheric and
orbital modeling errors. This technique “differences” the measurement of the carrier beat phase
across time, frequency, receivers, satellites, or any combination of these. The most popular
differences are single, double and triple.

Differential GPS (DGPS) is a positioni ng pr ocedure that uses tw o r ec ei v er s, a ro v er at an
unknown location and a reference station at a known, fixed location. The reference station
computes corrections based on the actual and observed ranges to the satellites being tracked.
The coordinates of the unknown location can be computed with sub-meter level precision by
applying these corrections to the satellite data received by the rover.

Dilution of Precision (DOP) is a class of measures of the magnitude of error in GPS position
fixes due to the orientation of the GPS satellites with respect to the GPS receiver. There are
several DOP’s to measure different components of the error. Note: this is a unit-less v alue. See
also PDOP.

Doppler Aiding is a signal processing strategy that uses measured Doppler shifts to help the
receiver smoothly track the GPS signal, allowing more precise velocity and position
measurement.

Doppler Shift is the apparent change in frequency of a received signal due to the rate of
change of the distance between the transmitter and receiver.

Double Difference between receivers and between satellites is found by differencing the single
difference for one satellite with the single difference for another satellite where both single
differences are from the same epoch.

Dual-Frequency is a type of GPS receiver that uses both L1 and L2 signal s from GPS
satellites. A dual-frequency receiver can compute more precise position fixes over longer
distances and under more adverse conditions because it compensates for ionospheric delays.

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Dynamic Mode when a GPS receiver operates in dynamic mode, it assumes that it is in motion
and certain algorithms for GPS position fixing are enabled in order to calculate a tighter position
fix.

Dynamic Positioning (GPS) is the determination of the position of a moving receiver such as
one mounted on a boat. Generally, each set of coordinates is computed from a single data
sample. The GPS was originally conceived for dynamic positioning of a single receiver,
however, it may be used in a differential mode to increase relative accuracy.

Eccentricity is the ratio of the distance from the center of an ellipse to its focus on the semi­major axis.

Elevation is the distance above or below Local Vertical Datum.
Elevation Mask the lowest elevation, in degrees, at which a receiver can track a satellite.

Measured from the horizon to zenith, 0º to 90º.
Ellipsoid is a mathematical model approximating the earth’s surface, generated by rotating an

ellipse on its minor axis. GPS positions are computed relative to the WGS-84 elli psoid. An
ellipsoid has a smooth surface, which does not match the earth’s geoidal surface closely, so
GPS altitude measurements can contain a large vertical error component. Conventionally
surveyed positions usually reference a geoid, which has an undulating surface and
approximates the earth’s surface more closely to minimize altitude errors.

Ephemeris is a tabulation of the positions of all GPS sat el l i tes at gi ven point s in ti m e.
Epoch is a period of time or a date selected as a point of reference.
Error Ellipse is a statistical measure of the positional error at a give n point computed fr om the

propagat i o n o f all error s a ff ecting the position s olution and expressed by its semi-major an d
semi-minor axis (vectors of greatest and least magnitude) and the covariance (rotation angle in
the reference coordinate system). Two-dimensional errors are typically propagated at one
standard deviation (39.4% probability that the positioning lies on or within the ellipse) or 2.1447
times the standard deviation (95% confidence) level.

European Geostationary Navigation Overlay Service (EGNOS) a European satellite system
used to augment the two military satellite navigation systems now operating, the US GPS and
Russian GLONASS systems.

Fractional Instantaneous Phase Measurement is a measurement of the carrier beat phase that
does not include any integer cycle count.

Frequency Band is a range of frequencies in a region of the electromagnetic spectrum.
Frequency Spectrum is the distr i bu ti on of signal am pli tudes as a function o f frequency of the

constituent signal waves.
Galileo is the navigation satellite system currently being developed and implemented by the

European Space Agency, the European Union. Initial operation is planned for 2008.
Geodetic Leveling Network is a network of vertical control or benchmarks whose heights are

known as accurately as possible, and whose horizontal position is known only approximately.
Geoid is the gravity -equipotential surface that best approximates mean sea level over the entire

surface of the earth. The surface of a geoid is too irregular to use for GPS readings, which are
measur ed r elat ive to an ellipsoid. C onventionally s ur vey e d pos it ions reference a ge oi d.
Calculating the distance between the geoid and ellipsoid at each position and subtracting this
from the GPS altitude measurement can obtain more accurate GPS readings.

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Geoidal Height is the undul ation of the geoid abo ve or below the referenc e el l ips oid.
Geographical Information System (GIS) is a computer system capable of assembling, storing,

manipulating, updating, analyzing and displaying geographically referenced information, i.e.
data identified according to their locations. GIS technology can be used for scientific
investigations, resource management, and development planning. GIS software is used to
display, edit, query and analyze all the graphical objects and their associated information.

Global Positioning System (GPS) geometrically, there can only be one point in space, which
is the correc t dis tance from each of four k n ow n po i nts . GPS measure s the di s t ance from a point
to at least fo ur satel l i te s from a constellation of 24 N AVSTAR satellite s or bi ti ng t he earth at a
very high altitude (approximately 20,200km). These distances are used to calculate the point’s
position.

GPS Aided Geo Augmented Navigation (GAGAN) is an Indian satellite system that provides
a set of corrections for the GPS satellites, which are valid for the Indian region. They incorporate
satellite orbit and clock corrections.

GPS Time is a measure of time. GPS time is based on UTC, but does not ad d per i o di c ‘le ap
seconds’ to correct for changes in the earth’s period of rotation. As of April 2008 GPS time is 14
seconds ahead of UTC.

Greenwich Mean Time (GMT) is the local time of the 0° meridian passing through Greenwich,
England.

Handover Word is the word in the GPS message that contains time synchronization
information for the transf er from th e C/ A-c od e t o t he P-code.

Horizontal Geodetic Network is a network f or which the horizontal, coordinate, latitude, and
longitud e of the control points in the network are determined as accurately as possible, and
heights ar e kn own onl y approxi mately.

Independent Baseline those basel ines that provi de a unique position sol ution for a given
station.

Integer-cycle Ambig u it y is the unknown number of whole carrier cycles between the satellite
and the receiver.

Ionosphere is the region of the earth’s atmosphere between the stratosphere and the
exosphere approximately 50 to 250 miles above the earth’s surface

Ionospheric Refraction Delay is a delay in th e propagation of the GPS signal caused by the
signal traveling through the ionosphere.

Issue of Data, Clock (IODC) indicates the iss u e n um ber of the data s et an d t hereby provides
the user with a convenient means of detecting any change in the correction parameters. The
transmitted IODC will be different from any value transmitted by the satellite during the
preceding seven days.

Kalma n Filtering is a linear system in which the mean squared error between the desired
output and the actual output is minimized when the input is a random signal generated by white
noise. The Kalman filter looks at a target to remove the effects of the noise and get a good
estimate of the location of the target at the present time (filtering), at a future time (prediction),
or at a time in the past (interpolation or smoothing). The Kalman filter is a recursive estimator
with two phases: predict and up date. The pre di ct phase uses the estima te from a prev ious state
to produce an estimate of the current state. The update phase uses the current state
measurements to arrive at a new more accurate estimate.

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L-band is the group o f radi o fre quencies exten ding from ap pr oxi m a tel y 40 0MHz to
approximately 1600MHz. The GPS carrier frequencies L1 (1575.4MHz) and L2 (1227.6 MHz)
are in the L-band range.

L1 carrier frequency is the primary L-band carrier used by GPS satellites to transmit satellite
data. The frequency is 1575.42MHz. It is modulated by C/A code, P-code, or Y-code, an d a 50­bit/second navigation message. The bandwidth of this signal is 1.023MHz.

L2 carrier frequency is the secondary L-band carrier used by GPS satellites to transmit
satellite data. The f requency is 1227.6MHz. It is modulated by P-code, or Y-code, and a 50­bit/second navigation message. The bandwidth of this signal is 10.23MHz.

Land Earth Station (LES) is the poi nt on t h e ear t h’ s sur fac e wh er e dat a is up link e d to a
satellite.

Latitude (lat) is the north/sout h com p onent of the coordinat e o f a point on the surface on the
earth; expressed in angular measurement from the plane of the equator to a line from the center
of the earth to the point of interes t. Often abbr ev iated as Lat.

Least Squares Adjustment is a mathematical technique used on data sets that attempts to find
the number t h at pr ov ides the ‘best fit’ to the data. It does so by minimizing the sum of the
squares of the residuals, which are the difference between the estimated ‘best fit’ and the data
point squared. It is carried out using an iterative process. Furthermore, it is a method of
determining the curve that best describes the relationship betwee n ex p ected and observed se ts
of data by mini m iz i n g the s um s of the squares of deviation be tw e en observed and exp ected
values.

LEMO is a type of data or power connector.
Logging Interval is the f requency at which positions generated by the receiver are logged to

data files .
Longitude (long) is the east/west component of the coordinate of a point on the surface of the

earth; expressed as an angular measurement from the plane that passes through the earth’s
axis of rotation and the 0° meridian and the plane that passes through the axis of rotation and
the point of interest. Often abbreviated as Lon.

Mean Sea Level (MSL) is a vertical surface that represents sea level.
Meridian one of the lines joining the north and south poles at ri g ht an gl es to the equator,

designa te d by degrees of longitud e, from 0° at Greenwich to 18 0° .
Meteorological (.YYm) files one of the three file types that make up the RINEX file format .

Where YY indicates the last two digits of the year the data was collected. A meteorological file
contains atmospheric information.

Monitor Station is one of five worldwide stations maintained by the DoD and used in the GPS
control segment to monitor and control satellite clock and orbital parameters. Corrections are
calculated and uploaded to each satellite at least once per day. See Control Segment.

MTSAT Sa tellite-based Augmentation System (MSAS is a Japanese satellite system that
provides a set of corrections for the GPS satellites, which are valid for the Japanese region.
They incorporate satellite orbit and clock corrections.

Multipath is a phenomenon whereby GPS signals from a satellite arrive at an antenna having
traversed different paths. The signal traversing the longer path may have been reflected off one

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or more objects —the ground, a vehicle, boat, building or some other surface—and once
receive d by the antenna, will yield a larger pseudo-range estimate and increase the error.

Multipath Error is a positioning error resulting from interference between radio waves that has
traveled between the transmitter and the receiver by two paths of different electrical lengths.

Navigation Code uses the two GPS carrier waves and operates on a very low frequency (about
50Hz). This code communicates the GPS message (a string of data) from the GPS satellites to
the GPS receivers on L1 and L2 carrier waves.

Navigation (.YYn) files one of the thr ee file typ es that mak e up the RINEX file form at. Wher e
YY indicates the last two digits of the year the data was collected. A navig ati o n file contains
satellite position and time information.

Navigation Message is the 1500-bit message broadcast by each satellite at 50bps on both L1
and L2 beacons. This message contains system time, clock correction parameters, ionospheric
delay model parameters, and the vehicle’s ephemeris and health. This information is used to
process the GPS signal to obtain user position and velocity.

NAVSTAR is the name given to GPS satellites, originally manufactured by Rockwell
International.

Observation (.YYo) file s one of the three file types that make up the RINEX file format . Where
YY indicates the last two digits of the year the data was collected. An observation file contains
raw GPS posit i on infor m ation.

P-code is the extremely long pseudo-random code generated by a GPS satel l ite. It is intende d
for use only by the U.S. military, so it can be encrypted to Y-code, and then deni es unauthorized
users access.

Parity is a method of detecting communication errors by adding an extra parity bit to a group of
bits. The parity bit can be a 0 or 1 value so that every byte will add up to an odd or even number
(depending on whether odd or even parity is chosen).

PDOP Mask is the highest PDOP value at which a receiver computes positions.
Perigee is the point in the orbit of a satellite about the earth that is the least distant from the

center of the earth.
Phase Center is the point in an antenna where the GPS signal from the satellites is received.

The height above ground of the phase center must be measured accurately to ensure accurate
GPS readings. The phase center height can be calculated by adding the height to an easily
measured point, such as the base of the antenna mount, to the known distance between this
point and the phase center.

Phase Lock is the technique where the phase of a signal is set to replicate the phase of a
reference signal by comparing the phase of the two signals and then using the resultant phase
difference to adjust the reference oscillator to eliminate the difference.

Phase Measurement is measurement expressed as a percentage of a portion of a wave (e.g. a
sine wave) . For ex am ple, a compl e t e wav elength

Position is the latitude, longitude, and altitude of a point. An estim at e of error is often
associated with a position.

Position Dilution of Precision (PDOP) is a measure of the magnitude of Dilution of Position
(DOP) errors in the x, y, and z coordinates.

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Post-processing is a method of differential data correction, which compares data logged from
a known reference point to data logged by a roving receiver over the same period of time.
Variations in the position reported by the reference station can be used to correct the positions
logged by the roving receiver. Post-processing is performed after the user collects the data and
returns to the office, rather than in real time as data is logged, so it can use complex,
calcula ti on s to ac hieve greater accur ac y.

Precise code see P-code.
Precise Ephemeris is the ephemeris computed after the transmission of the satellite signal and

based on satellite tracking information. It is used in post-processing of collected GPS data.
Precision is the degree of agreement or repeatability among a series of individual

measurements, values, or results. The precision of a numerical value can refer to the num ber of
significant digits used to express a quantity or that an instrument can measure to. Precision is
related to the quality of the operation through which the result is obtained.

PRN (Uppercase) typically indicates a GPS satell ite number seque nce fr om 1 – 32.
Projection is a mathematical formula that transforms feature locations between the earth’s

curved surface and a map’s flat surface. A projected coordinate system includes the information
needed to tr an sform locations expr es sed as latitude values to x,y coordinates. Projections
cause distortion in one or more of these spatial properties-distance, area, shape and direction.

Protected code see P-code.
Pseudo-Random Noise (prn) is a sequence of data that appe ar s to be r andomly distribu ted

but can be exactly reproduced. Each GPS satellite transmits a unique PRN in its signals. GPS
receivers use PRNs to identify and lock onto satellites and to compute their pseudoranges.

Pseudorange is the apparent distance from the reference station’s antenna to a satelli te,
calculated by multiplying the time the signal takes to reach the antenna by the speed of light
(radio waves travel at the speed of light). The actual distance, or range, is not exactly the same
because various factors cause errors in the measurement.

Radio Technical Commission for Maritime Services (RTCM) is a standard form at for
Differential GPS corrections used to transmit corrections from a base station to rovers. RTCM
allows both real-time kinematic (RTK) data collection and post-processed differential data
collection. RTCM SC-104 (RTCM Special Committee 104) is the most commonly used version
of RTCM message.

Range is the distance between a satellite and a GPS receiver’s antenna. The range is
approximately equal to the pseudorange. However, errors can be introduced by atmospheric
conditions, which slow down the radio waves, clock errors, irregularities in the satellite’s orbit,
and other factors. A GPS receiver’s location can be determined if you know the ranges from the
receiver to at l east four GPS satellites. Geometrically, there can only be one point in space,
which is th e corr e c t di stance from each of fo ur kno w n poi nts.

Rea l Time GIPSY (RTG) is a processing technique developed by NASA’s Jet Propulsi on
Laboratory to prov i d e a sin gl e set of real time global corrections for the GPS satellites.

Real-Time Kinematic (RTK) is a GPS system that yields very accurate 3D position fixes
immediately in real-time. The base station transmits its GPS position to roving receivers as the
receiver ge nerates them, and the roving receivers use the base station readings to differentially
correct their own positions . Ac curacies of a few centi m eters in all three dime ns ions are possible.
RTK requires dual frequency GPS receivers and high speed radio modems.

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Receiver Independent Exchange (RINEX) i s a set o f sta ndard definitions an d f orm at s
designed to be receiver or software manufacturer independent and to promote the free
exchange of GPS data. The RINEX file format consists of separate files, the three most
commonly used are:

Observat i o n (.Y Yo) file,
Navigation (.YYn) file,

Meteorological (.YYm) files;
Where YY indicates the last two digits of the year the data was collected.
Reference station a reference station collects GPS data for a fixed, known location. Some o f

the errors in the GPS positions for this location can be applied to positions recorded at the same
time by roving receivers which are relatively close to the reference station. A reference station is
used to improve the quality and accuracy of GPS data collect ed by roving receivers.

Right Hand Circular Polarization (RHCP) is used to discriminate satellite sig na ls . GPS signals
are RHCP.

Root Mean Square (RMS) is a measurement of precision also applicable for horizontal stations.
Probability fo r RMS is 68.3%, meaning that if 100 observations are made, 68 of them will be
within the root mean square, 1 standard deviation.

Rover is any mobile GPS receiver and field computer collecting data in the field. A roving
receiver’s position can be differentially corrected relative to a stationary reference GPS receiver
or by using GPS orbit and clock corrections from a SBAS suc h as C-Nav.

Roving Receiver see rover
Satellite Based Augmentation System (SBAS) this is a more general term, which

encompa s ses WAAS, C-Nav and EGNOS type corrections.
Satellite C onstellat ion is the arrangement of a set of satellites in space.
Satellite Message is sometimes referred to as the Data (D) code. A low-f requency (50 Hz)

stream o f data on both carr i er s (L 1 and L2) of the satellite signal. The stream of data is
designed to inform the user about the health and position of the satellite. The satellite message
can be decoded by the receiver and used for positioning in real time.

Selective Availability (S/A) is the deliberate degradation of the GPS signal by encrypting the
P-code and dithering the satellite clock. When the US Department of Defense uses S/A, the
signal contains errors, which can cause positions to be inaccurate by as much as 100 meters.

Signal-to-Noise Ratio (SNR) is a measure of a satellite’s signal strength.
Single Diff erence between receivers is the instantaneous difference in the complete carrier

beat phase measurements made at two receivers simultaneous observing the same signal.
Single-frequency is a type of receiv er that only uses the L1 GPS signal. There is no

compensation for ionospheric effects. The C-Nav1010 is a single frequency receiver.
Space Segm en t is the portion of the GPS system with major components in space (e.g.,

satellites).

Space Vehi cle (SV) a GPS satellite.
Spread Spectrum Radio (SSR) is a radio that uses wide band, noise like (pseudo-noise)

signals that are hard to detect, intercept, jam, or demodulate making a ny data transmitte d

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secure. Because spread spectrum signals are so wide, they can be transmitted at much lower
spectral power density (Watts per Hertz), than narrow band signals.

Standard Deviation is a measure of how widely values are dispersed from the mean. The
larger the standard deviation is, the more spread out the values are from the mean. It is the
square root of the average squared deviations of each of the values from the mean.

Time Tag is when a time value is appended to an actual measurement.
Triple Difference between receivers, between satellites, and between epochs (time) is the

difference between a double difference at one ep o c h and the s am e do uble difference at t he
following epoch.

Troposphere is the inner layer of the atmosphere, located between 6 and 12 miles above the
earth’s surface.

Twice Distance Root Mean Square (2dRMS) is a measurement that varies in its probability
from 95.4 % to 98.2%, meaning tha t i f 100 observations are tak en , bet ween 95 and 98 of those
observations will be within the 2dRMS where approximation = 2ơ

Universal Time Coordinated (UTC) a time standard maintained by the US Naval Observatory,
based on local solar mean time at the Greenwich meridian. GPS time is based on UTC.

User Segment is the portion of the GPS system with major components that can be interfaced
by the user (e.g., GPS receivers).

Wide Area Augmentation System (WAAS) is a set of corrections for the GPS satellites, which
are valid for the Americas region. They incorporate satellite orbit and clock corrections.

Wide Area Differential GPS (WADGPS) is a set of corrections for the GPS satellites, which are
valid for a wide geographic area.

World Geodetic System 1984 (WGS84) is the current standard datum for global positioning
and surveying. The WGS-84 is based on the GRS-80 ellipsoid .

Y-code is the name given to encrypted P-code when the U.S. Department of Defense uses
selective availab ility.

Z-count Word is the GPS satellite clock time at the leading edge of the data subframe of the
transmitted GPS message.

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