NavCom RT-3020 User Manual Rev.F

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NavCom Technology, Inc.

20780 Madrona Avenue Torrance, California 90503 USA

Tel: +1 310.381.2000 Fax: +1 310.381.2001

sales@navcomtech.com www.navcomtech.com

P/N: 9

31000

3001

RT-3020 User Guide – Rev. F

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RT-3020 User Guide – Rev. F

List of Figures..........................................................iv

List of Tables ............................................................ v

Notices ...........................................................vi

Trademarks ................................................................vi

FCC Notice................................................................. vi

User Notice................................................................ vii

Limited Warranty .......................................................viii

StarFire™ Licensing...................................................ix

USG FAR....................................................................ix

Global Positioning System ......................................... ix

Revision History.......................................................xi

Use of this Document.............................................xii

Related Documents.......................................................xii

StarUtil User Guide.................................................... xii

Technical Reference Manual.....................................xiii

RINEXUtil User Guide...............................................xiii

Integrators Toolkit......................................................xiii

NavCom Release Notes............................................xiii

Related Standards........................................................ xiv

ICD-GPS-200 ........................................................... xiv

RTCM-SC-104.......................................................... xiv

CMR, CMR+............................................................. xiv

NMEA-0183.............................................................. xiv

Publicly-Operated SBAS Signals ............................. xiv

Chapter 1 Introduction .....................................17

System Overview...........................................................17

GPS Sensor System .................................................17

Accuracy....................................................................18

Features ....................................................................18

Output Data Rate.......................................................18

NCT Binary Proprietary Data.....................................19

NMEA-0183 Data ......................................................20

Models ...........................................................................21

RT-3020S..................................................................21

RT-3020M..................................................................21

Antennae........................................................................22

Standard....................................................................22

Spread Spectrum Radio Antenna..............................22

RT-3020 User Guide – Rev. F

Airborne (option)........................................................23

Controller.......................................................................23

Applications...............................................................26

Unique Features............................................................26

Chapter 2 Interfacing........................................ 29

Electrical Power.........................................................29

Communication Ports................................................32

CAN Bus/Event .........................................................35

Event .........................................................................35

1 PPS ........................................................................36

Indicator Panel...............................................................37

Chapter 3 Installation....................................... 41

Standard Antenna .....................................................41

GPS Sensor...............................................................43

Block Diagram...........................................................45

Communication Port Connectivity.............................46

GPS Antenna Connector...........................................48

SSR Antenna Connector...........................................50

Basics of RTK Surveying...............................................50

Chapter 4 Configuration .................................. 53

Factory Default Settings ................................................54

Message Descriptions...............................................56

3rd Party Controller Configuration Settings................57

Chapter 5 Safety Instructions.......................... 59

Transport...................................................................59

RF Exposure Compliance.........................................59

Maintenance..............................................................59

External Power Source..............................................60

Safety First ................................................................60

A GPS Module Specifications.............................61

Features ....................................................................61

Time-To-First-Fix.......................................................62

Dynamics...................................................................63

Measurement Performance.......................................63

User programmable output rates ..............................64

Data Latency .............................................................64

1PPS .........................................................................64

Built-in Radio Performance .......................................65

Connector Assignments............................................65

Input/Output Data Messages.....................................66

LED Display Functions (Default)...............................66

Satellite Based Augmentation System Signals.........67

RT-3020 User Guide – Rev. F

Physical and Environmental......................................67

B Antenna Specifications ....................................69

Radiation Pattern.......................................................71

C Event Input Configuration................................75

Glossary ..........................................................77

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RT-3020 User Guide – Rev. F

List of Figures

Figure 1: RT-3020 Supplied Equipment..................25

Figure 2: Universal Power Adapter.......................... 30

Figure 3: AC Power Cord ........................................ 30

Figure 4: Optional DC Power Cable........................31

Figure 5: RT-3020 Front View.................................33

Figure 6: NavCom Serial Cable...............................34

Figure 7: RT-3020M Only Back View......................35

Figure 8: RT-3020 Indicator Panel .......................... 37

Figure 9: Standard GPS/L-band Antenna................ 41

Figure 10: RT-3020 Base Plate Dimensions...........44

Figure 11: RT-3020S/M Block Diagram................... 45

Figure 12: Radio Port Configuration, StarUtil..........46

Figure 13: Communication Port Connections..........47

Figure 14: RTK setup – Good Line of Sight............. 52

Figure 15: RTK Setup – Poor Line of Sight.............52

Figure 16: StarUtil NMEA Message List.................. 54

Figure 17: StarUtil Rover Navigation Setup............. 55

Figure 18: PN: 82-001002-3002 Ant Dimensions....70

Figure 19: AN-2004T Radiation Pattern..................71

Figure 20: PN: 82-001002-3001 Ant Dimensions....73

Figure 21: Event Cable Wiring Diagram.................. 75

Figure 22: PPS & Event Latch Configuration .......... 76

Figure 23: Event Latch Output Rate........................ 76

Figure 24: DTE to DCE RS-232 Pin Assignments... 80

RT-3020 User Guide – Rev. F

List of Tables

Table 1: Supplied Equipment...................................25

Table 2: External Power Cable Pin-Out...................29

Table 3: Optional DC Pwr Cable Pin Assignments..31

Table 4: Serial Cable Pin-Outs ................................33

Table 5: Link LED Indication (Default Rover Mode).38

Table 6: Base Station Indication..............................38

Table 7: GPS Light Indication..................................39

Table 8: Acceptable Cable Lengths.........................48

Table 9: Factory Setup Proprietary Msgs COM 2....56

Table 10: Standard Antenna....................................69

Table 11: SSR Antenna (with mount) ......................72

Table 12: Event Wiring Connections........................75

RT-3020 User Guide – Rev. F

Notices

RT-3020 GPS Products User Guide P/N 96-310005-3001 Revision F August 2008

Serial Number:

Date Delivered:

Purchased From:

Copyright

computer program(s) described herein may be reproduced, stored, or transmitted by any means, without the expressed written consent of the copyright holders. Translation in any language is prohibited without the expressed written consent of the copyright holders.

Trademarks

‘find your way’, ‘NavCom Globe’ and ‘NAVCOM TECHNOLOGY’ logos are trademarks of NavCom Technology, Inc. StarFire™ is a registered trademark of Deere & Company. All other product and brand names are trademarks or registered trademarks of their respective holders.

FCC Notice

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:

RT-3020 User Guide – Rev. F

1. This device may not cause harmful interference, and

2. This device must accept any interference received, including interference that may cause undesired operation.

The GPS sensor has been tested in accordance with FCC regulations for electromagnetic interference. This does not guarantee non-interference with other equipment. Additionally, the GPS sensor may be adversely affected by nearby sources of electromagnetic radiation.

The Global Positioning System is under the control of the United States Air Force. Operation of the GPS satellites may be changed at any time and without warning.

User Notice

NavCom Technology, Inc. shall not be responsible for any inaccuracies, errors, or omissions in information contained herein, including, but not limited to, information obtained from third party sources, such as publications of other companies, the press, or competitive data organizations.

This publication is made available on an “as is” basis and NavCom Technology, Inc. specifically disclaims all associated warranties, whether express or implied. In no event will NavCom Technology, Inc. be liable for direct, indirect, special, incidental, or consequential damages in connection with the use of or reliance on the material contained in this publication, even if advised of the possibility of such damages. NavCom Technology, Inc. reserves the right to make improvements or changes to this publication and the products and services herein described at any time, without notice or obligation.

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RT-3020 User Guide – Rev. F

Limited Warranty

NavCom Technology, Inc., warrants that its products will be free from defects in workmanship at the time of delivery. Under this limited warranty, parts found to be defective or defects in workmanship will be repaired or replaced at the discretion of NavCom Technology, Inc., at no cost to the Buyer, provided that the Buyer returns the defective product to NavCom Technology, Inc. in the original supplied packaging and pays all transportation charges, duties, and taxes associated with the return of the product. Parts replaced during the warranty period do not extend the period of the basic limited warranty.

This provision does not extend to any NavCom Technology, Inc. products, which have been subjected to misuse, accident or improper installation, maintenance or application, nor does it extend to products repaired or altered outside the NavCom Technology, Inc. production facility unless authorized in writing by NavCom Technology, Inc.

This provision is expressly accepted by the buyer in lieu of any or all other agreements, statements or representations, expressed or implied, in fact or in law, including the implied warranties of merchantability and fitness for a particular purpose and of all duties or liabilities of NavCom Technology, Inc. To the buyer arising out of the use of the goods, and no agreement or understanding varying or extending the same will be binding upon NavCom Technology, Inc. unless in writing, signed by a dulyauthorized officer of NavCom Technology, Inc.

This limited warranty period is one (1) year from date of purchase.

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RT-3020 User Guide – Rev. F

StarFire™ Licensing

The StarFire™ signal requires a subscription that must be purchased in order to access the service. Licenses are non-transferable, and are subject to the terms of the StarFire™ Signal License agreement. For further details on the StarFire™ Signal Network, its capabilities, terms and conditions visit

www.navcomtech.com sales@navcomtech.com

or send an email inquiry to

USG FAR

Technical Data Declaration (Jan 1997) The Contractor, NavCom Technology, Inc., hereby

declares that, to the best of its knowledge and belief, the technical data delivered herewith under Government contract (and subcontracts, if appropriate) are complete, accurate, and comply with the requirements of the contract concerning such technical data

Global Positioning System

Selective availability (S/A code) was disabled on 02 May 2000 at 04:05 UTC. The United States government has stated that present GPS users use the available signals at their own risk. The US Government may at any time end or change operation of these satellites without warning.

The U.S. Department of Commerce Limits Requirements state that all exportable GPS products contain performance limitations so that they cannot be used to threaten the security of the United States.

Access to satellite measurements and navigation results will be limited from display and recordable output when predetermined values of velocity and altitude are exceeded. These threshold values are far

RT-3020 User Guide – Rev. F

in excess of the normal and expected operational parameters of the RT-3020 GPS Sensor.

Revision History

Rev F (Aug 2008)

RT-3020 User Guide – Rev. F

Format change Added Revision History Updated Supplied Equipment

Revised photo Added new PN for SSR antenna (includes mount)

Replaced old art work of

RT-3020 dimensions with new art work

Replaced old photos of standard

antenna dimensions with new

photos Added RT-3020 block diagram Added section, SSR Antenna

Connector, to Chapter 3 Added specs for SSR antenna to

Appendix B Added airborne antenna option &

dimensional drawing Added specs for UltraRTK™ Added NMEA message GBS Corrected in Appendix A, the

Antenna Power spec of

5 VDC, 0.05mA to

4.6 VDC, 50mA max

RT-3020 User Guide – Rev. F

Use of this Document

This User Guide is intended to be used by someone familiar with the concepts of GPS and satellite surveying equipment.

 Note indicates additional information

to make better use of the product.

This symbol means Reader Be

Careful. Indicates a caution, care, and/or safety situation. The user might do something that could result in equipment damage or loss of data.

This symbol means Danger. You are in

a situation that could cause bodily injury. Before you work on any equipment, be aware of the hazards involved with electrical and RF circuitry and be familiar with standard practices for preventing accidents.

Revisions to this User Guide can be obtained in a digital format from

http://www.navcomtech.com/Support/

Related Standards

ICD-GPS-200

NAVSTAR GPS Space Segment / Navigation User Interfaces Standard. ARINC Research Corporation; 2250 E. Imperial Highway; El Segundo, California 90245

RTCM-SC-104

Recommended Standards For Differential GNSS Service. Radio Technical Commission For Maritime Services; 1800 N. Kent St, Suite 1060; Arlington, Virginia 22209

CMR, CMR+

Compact Measurement Record; Trimble Navigation Limited; 935 Stewart Drive; Sunnyvale, CA 94085

NMEA-0183

National Marine Electronics Association Standard For Interfacing Marine Electronic Devices. NMEA National Office; 7 Riggs Avenue; Severna Park, Maryland 21146

Publicly-Operated SBAS Signals

RTCA/DO-229D

The Radio Technical Commission for Aeronautics (RTCA) develops consensus-based recommendations regarding communications, navigation, surveillance, and air traffic management (CNS/ATM) system issues.

RTCA. 1828 L Street, NW, Suite 805, Washington, DC 20036.

These organizations implement the RTCA/DO-229D standard set by RTCA:

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RT-3020 User Guide – Rev. F

WAAS (Wide Area Augmentation System)

U.S. Department of Transportation. Federal Aviation Administration. 800 Independence Ave, SW, Washington, DC 20591

EGNOS (European Geostationary Navigation Overlay Service)

European Space Agency. 8, 10 rue Mario-Nikis, F75738 Paris Cedex 15, France.

MSAS (MTSAT Satellite-based Augmentation System)

Japan Civil Aviation Bureau. Ministry of Transport. Kasumigaseki 2-1-3, Chiyoda-ku, Tokyo 100, Japan.

GAGAN (GPS Aided Geo Augmented Navigation)

Indian Space Research Organization. Antariksh Bhavan, New Bel Road, Bangalore - 560 094, India.

RT-3020 User Guide – Rev. F

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RT-3020 User Guide – Rev. F

Chapter 1 ..............................Introduction

System Overview

GPS Sensor System

The RT-3020 GPS sensor delivers unmatched accuracy to the precise positioning community. This unique receiver is designed to integrate easily into a wide variety of surveying and machine control applications.

The RT-3020 has a built-in spread spectrum radio (SSR), a geodetic-quality GPS antenna, and onboard 64MB memory for millimeter level position accuracy from post-processing. The receiver may be configured as base or rover. It is capable of NCT

RTK/

UltraRTK™, RTCM (code and phase v2.3), and

CMR/CMR+ DGPS operating methods. The RT-3020 integrated sensor consists of:

9 Built-in spread spectrum radio (SSR) 9 24-channel, dual-frequency, precision GPS

receiver

9 2 separate SBAS channels, RTCA/DO-229D

compliant (WAAS/EGNOS/MSAS/GAGAN)

There are two models, the RT-3020S and the RT-3020M. Packaging and performance standards of the models are the same; the differences lie in the features, as described later in this chapter.

Refer to Table 1, later in this chapter, for the complete list of supplied equipment.

Requires NCT-2100D Engine

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RT-3020 User Guide – Rev. F

Accuracy

When WAAS, EGNOS, MSAS, or GAGAN (RTCA/DO-229D compliant) SBAS correction signals are used, the system provides <50cm position accuracy.

 System accuracy with WAAS,

EGNOS, MSAS, or GAGAN signals is subject to the quality and update rate of these publicly-operated signals. Refer to Related Standards\Publicly- Operated SBAS Signals for contact information regarding the organizations that implement the RTCA/DO-229D standard.

The system provides instant <0.5cm position accuracy when

UltraRTK™ correction signals are used (base-line, <40km, 0.5cm +1ppm). UltraRTK™ requires GPS software version 4.2 or higher.

The system provides instant <1cm position accuracy when RTK correction signals are used (base-line, <10km, 1cm +1ppm).

 After RTK correction signals are

received, it takes approximately one minute to enter RTK mode.

Features Output Data Rate

The RT-3020 can output proprietary raw data at programmable rates from < rates up to 50Hz

and Position Velocity Time (PVT) data at programmable rates from < predetermined rates up to 25Hz

Requires NCT-2100D Engine. 2Separate Software Option

Required. Standard Output Data Rates Are Model Dependent.

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1Hz to predetermined

1Hz to

through two 115kbps

RT-3020 User Guide – Rev. F

RS-232 serial ports with less than 20ms latency.

1cm horizontal and <2cm vertical accuracy are

< maintained as each output is independently calculated based on an actual GPS position measurement, as opposed to an extrapolation/interpolation between 1Hz measurements.

The system resolves ambiguities at startup or on satellite reacquisition typically within 2 seconds.

The standard output data rates for the RT-3020M only are <

25Hz for proprietary raw data and <10Hz

for PVT data.

NCT Binary Proprietary Data

The sensor can output proprietary raw data containing information including (but not limited to):

9 Satellite Ephemeris (0x81) 9 Satellite Almanac (0x44) 9 Raw Pseudorange Measurements (0xB0) 9 Position, Height, & Time (0xB1) 9 Velocity & Heading (0xB1) 9 Signal to Noise (0x86) 9 Channel Status (0x86) 9 Correction Data (mirror data; 0xEC) 9 Event/Marker (M model only; 0xB4) 9 Measurement Quality (0xB1 and 0xB5)

These data can be integrated in real-time positioning applications or post-processed against any number of software applications designed to handle NCT or RINEX raw data. A Technical Reference Manual is available on NavCom’s web site, which describes the attributes of each of the input/output records (see Related Documents in the fore-matter).

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RT-3020 User Guide – Rev. F

NMEA-0183 Data

The RT-3020 is capable of outputting several standard NMEA-0183 data strings (see Related Standards in the fore-matter) and one proprietary data sting. Each data is headed with GP. The proprietary data sting is denoted with a $PNCT header.

Standard:

9 ALM – GPS Almanac Data 9 GBS – GNSS Satellite Fault Detection 9 GGA – GPS Fix Data 9 GLL – Geographic Position – Lat / Lon 9 GSA – GNSS DOP & Active Satellites 9 GST – GNSS Pseudorange Error Statistics 9 GSV – GNSS Satellites In View 9 RMC – Recommended Min. Specific GNSS Data 9 VTG – Course Over Ground & Ground Speed 9 ZDA – Time & Date

Proprietary (header $PNCT):

9 SET – Solid Earth Tide

Described in the Technical Reference Manual (see Related Documents in the fore-matter)

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RT-3020 User Guide – Rev. F

Models

RT-3020S

This model is designed for:

9 Construction Stakeout 9 Boundary Surveys 9 High Order Control Surveys 9 Topographic Surveys In Rough Terrain.

The sensor can be carried in a backpack with the antenna either pole-mounted from the backpack or on a survey pole with a single cable connection. It can be powered from portable, rechargeable batteries, which allow a full day’s operation.

RT-3020M

This model is ideal for vehicle mounting to suit a wide variety of machine guidance and control applications in:

9 Construction 9 Agriculture 9 Mining 9 Military

It is equipped with additional features allowing interconnectivity with a wide variety of antennas, vehicle data busses and other instrumentation to suit specific applications and configurations. Features that distinguish this model include:

9 A 1PPS output port 9 A combined Event/CAN Bus interface port

 The GPS antenna port provides 4.3VDC.

Care must be taken to select an appropriately rated GPS antenna if the standard NavCom antenna is not used.

An Event latch interface may be necessary for mechanically

devices (i.e. camera shutter)

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RT-3020 User Guide – Rev. F

Antennae

Standard

The standard integrated antenna (PN: 82-001002-

3002) tracks all GPS, WAAS, EGNOS, MSAS, GAGAN, and StarFire™ signals. The compact GPS antenna has excellent tracking performance and a stable phase center for GPS L1 and L2. This antenna is listed in the NOAA GPS Antenna Calibration tables, as NAVAN2004T. The robust housing assembly features a standard 5/8” BSW thread for mounting directly to a surveyo pole, tripod, or mast and is certified to 70,000 feet (see Specifications for restrictions).

r’s

 Although rated to 70K feet, this antenna is not

designed for aircraft installations. Contact

sales@navcomtech.com

for aircraft solutions.

Spread Spectrum Radio Antenna

The RT-3020, configured as a reference station or rover, communicates via the integrated 2-way, 2.4GHz Spread Spectrum Radio (SSR). The SSR was designed specifically for GPS RTK. It has built-in interference rejection to prevent extraneous radio signals from interfering with the reception or transmission of the correction data.

The supplied SSR 2.4GHz Radio Antenna (PN: 91310020-3001) includes the antenna with mount. The antenna has a black polyurethane finish and a female TNC connector.

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RT-3020 User Guide – Rev. F

 The SSR 2.4GHz Radio Antenna

without mount (PN: 82-001000-0003) is an option.

 The RT-3020 complies with FCC

exposure limits. Individuals are required to be a minimum of 20 cm (8 in) away from the SSR transmitting antenna when used in the basic configuration. If the transmitting system is modified from the basic setup, check FCC regulations for compliance with exposure limits.

Airborne (option)

The airborne integrated antenna (PN: 82-001002-

3001) tracks all GPS, WAAS, EGNOS, MSAS, GAGAN, and StarFire™ signals. The compact GPS antenna has excellent tracking performance and a stable phase center for GPS L1 and L2. This antenna is listed in the NOAA GPS Antenna Calibration tables, as NAVAN2008T. The robust housing assembly features a flat mounting surface with four mounting holes and a downward facing TNC connector. This antenna is also certified to 70,000 feet (see Specifications for restrictions).

Controller

The RT-3020 GPS sensor is designed for use with an external controller solution connected via one of two serial COM ports.

This may be accomplished using a PC, Tablet PC or Personal Digital Assistant (PDA) and a software program which implements the rich control language

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RT-3020 User Guide – Rev. F

defined for NavCom GPS products. Refer to the user’s guide of your controller solution for further information. NavCom lists several application software solutions on our website:

http://www.navcomtech.com/Support/ApplicationSoftware.cfm

In addition, NavCom provides a Windows™ based software utility, called StarUtil, with the receiver.

The StarUtil User Guide, P/N 96-310008-3001, is available on-line at

http://www.navcomtech.com/Support/DownloadCenter.cfm?categ ory=manuals.

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RT-3020 User Guide – Rev. F

Included Items

Figure 1: RT-3020 Supplied Equipment

Table 1: Supplied Equipment

RT-3020 GPS Sensor

(RT-3020S P/N 92-310054-3001) (RT-3020M P/N 92-310054-3002)

Compact L1/L2 Tri-Mode GPS Antenna

(P/N 82-001002-3002) GPS Antenna Cable, 12 ft

(P/N 94-310058-3012) SSR 2.4GHz Radio Antenna with Mount

(P/N 91-310020-3001) LEMO 7-Pin to DB9S Data Cable, 6 ft

(P/N 94-310059-3006) CD-Rom containing User Guides, brochures, software

utilities, and technical papers. (P/N 96-310006-3001)

LEMO 4-Pin Universal AC/DC Power Adapter 12vdc, 2A

(P/N 82-020002-5001) SSR Antenna Cable, 3 ft {Not Shown}

(P/N 94-310065-3003) RT-3020 User’s Guide {Not Shown}

(P/N 96-310005-3001) Ruggedized Travel Case {Not Shown}

(P/N 79-100100-0002)

11 American 2-Pin AC power Cord, 10 ft {Not Shown}

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RT-3020 User Guide – Rev. F

Applications

The RT-3020 GPS sensor meets the needs of a large number of applications including, but not limited to:

9 High-Order Control Survey 9 Construction Stakeout 9 Boundary Survey 9 Topographical Survey 9 Machine Control

NavCom lists several application software solutions on our website:

http://www.navcomtech.com/Support/ApplicationSoft ware.cfm

Unique Features

The RT-3020 GPS sensor has many unique features:

 NCT RTK/UltraRTK™

The RTK/UltraRTK™ algorithm developed by NavCom provides fast initialization and the NCT ultra compact binary data format for RTK/UltraRTK™ ensures robust data throughput on the built-in spread spectrum radio.

 Positioning Flexibility

The RT-3020 is capable of using WAAS, EGNOS, MSAS, GAGAN (RTCA/DO-229D compliant) code corrections via two internal Satellite Based Augmentation System (SBAS) channels. The RT-3020 automatically configures to use the most suitable correction source available and changes as the survey dictates (this feature can be overridden).

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RT-3020 User Guide – Rev. F

 Data Sampling

RT-3020S GPS L1 and L2 raw measurement data is up to 5Hz

in the standard configuration. An optional upgrade allows 10, 25, and 50Hz raw measurement data via either of the two serial ports.

The PVT (Position, Velocity, & Time) data is output at up to 5 Hz in the standard configuration. An optional upgrade allows 10 and 25Hz position updates for highly dynamic applications.

RT-3020M GPS L1 and L2 raw measurement data is up to 25Hz

in the standard configuration. An optional upgrade allows 50Hz raw measurement data via either of the two serial ports.

The PVT (Position, Velocity, & Time) data is output at up to 10 Hz in the standard configuration. An optional upgrade allows 25Hz position updates for highly dynamic applications.

 GPS Performance

The RT-3020 utilizes NavCom’s NCT-2100 GPS engine, which incorporates several patented innovations. The engine’s industry leading receiver sensitivity provides more than 50% signal to noise ratio advantage over competing technologies. This results in improved real time positioning, proven through independent tests, when facing various multipath environments.

 Rugged Design

Units have been tested to conform to MIL-STD-810F for low pressure, solar radiation, rain, humidity, saltfog, sand, and dust.

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RT-3020 User Guide – Rev. F

The rugged design of the RT-3020 system components provides protection against the harsh environments common to areas such as construction sites, offshore vessels, and mines.

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RT-3020 User Guide – Rev. F

Chapter 2 .................................Interfacing

This chapter details the RT-3020 GPS sensor connectors, LED display, appropriate sources of electrical power, and how to interface the communication ports.

Electrical Power

A 4-pin LEMO female connector provides electrical power to the RT-3020. It is located below the indicator panel labeled DC PWR. Pin assignments are given in Table 2; see Figure 4 for pin location on the connector.

Table 2: External Power Cable Pin-Out

Pin Description

1 2 3 4

Pins 1 and 2 connect to the same internal point in the RT-3020. Likewise, pins 3 and 4 connect to the same internal point. The supplied power cable is constructed using 26 AWG wire.

Return

Power Input 10 to 30 VDC; 5W

 Power cable longer than 5m (15ft) must make

full use of all four power pins.

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RT-3020 User Guide – Rev. F

The RT-3020 is the supplied universal AC/DC 12V, 2A power adapter (P/N 82-020002-5001).

Figure 2: Universal Power Adapter

 Replacement AC power cords are

available through small appliance retailers (Radio Shack, Walmart, Best Buy, etc.)

Figure 3: AC Power Cord

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RT-3020 User Guide – Rev. F

P/N 94-310060-3010 is an optional 10ft (3m) unterminated power cable fitted with a LEMO plug type (Mfr. P/N FGG.1K.304.CLAC50Z), with red strain relief. The wiring color code and pin assignments are labeled on the cable assembly and provided in Table 3 below.

Table 3: Optional DC Power Cable Pin Assignments

Color Signal Pin No

Black 1

Brown

Red 3

Orange

Figure 4: Optional DC Power Cable

The GPS sensor is protected from reverse polarity with an inline diode. It will operate on any DC voltage between 10 and 30VDC, 5 watts (maximum).

Return

Power

 Voltages less than 10VDC will turn the

unit off. To turn the unit on, power must be in the 10 to 30VDC range. Press and hold the I/O switch in for more than 3 seconds.

To set the receiver to power up as soon as power is applied to the DC Input port, refer to the StarUtil Users Guide, Power Management or the

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RT-3020 User Guide – Rev. F

Technical Reference Manual, 0x32 Power Mode Configuration.

Voltages in excess of 30VDC will

damage the unit. The power supply must be well conditioned with surge protection. Vehicular electrical systems which create voltage spikes in excess of 30VDC will benefit from providing power protection during vehicle engine power-up. This can be accomplished through a relay power-on sequence and/or power conditioning (such as a DC to DC converter). Do not connect equipment directly to the vehicles battery without in-line protection (such as a DC to DC converter).

Communication Ports

The RT-3020 provides two 7-pin female LEMO connector communication ports labeled COM1 and COM2 located at the bottom front of the sensor, as shown in Figure 5. Each conforms to the EIA RS-232 standard with data rates from 1.2 to 115.2kbps. The connector pin-outs are described in Table 4. The supplied interface data cable (P/N 94-310059-3006) is constructed as described in Figure 6. The RT-3020 is configured as a DCE device. Laptop and desktop computers are configured as DTE devices, therefore a straight-through cable provides proper connectivity (PC TXD pin 2 connects to RT-3020 RXD pin 2).

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RT-3020 User Guide – Rev. F

Table 4: Serial Cable Pin-Outs

LEMO

Pins

Signal Nomenclature [DCE w/respect to DB9]

CTS - Clear To Send 5VDC to TruBlu

2 RD - Receive Data 2 3 TD - Transmit Data 3 4 DTR - Data Terminal Ready 4 5 RTN - Return [Ground] 5 6 DSR - Data Set Ready 6 7 RTS - Request To Send 7

DB9S

Pins

Figure 5: RT-3020 Front View

TruBlu – NavCom’s Bluetooth wireless accessory; S/N >5000

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RT-3020 User Guide – Rev. F

PN: 94-310059-3006

RD (per DCE Standard Definition) TD (per DCE Standard Definition)

DTR

GND

DSR RTS

CTS / 5VDC

DB9S

1 2 3 4 5 6 7 8

NavCom

Reciever

LEMO

1 2 3 4 5 6 7

07-00039-A

Figure 6: NavCom Serial Cable P/N 94-310059-3006

Connect pin 5 to shield of cable at both ends.

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RT-3020 User Guide – Rev. F

Figure 7: RT-3020M Only Back View

CAN Bus/Event

The RT-3020M provides a balanced (differential) 2-wire CAN Bus technology interface, ISO11898 -24V compliant. The CAN interface uses an asynchronous transmission scheme employing serial binary interchange widely used in the automotive industry. The data rate is defined as 250Kbps maximum with termination resistors at each end of the cable. This port/connector is shared with the Event Input.

 CAN Bus specifications are diverse.

Drivers for the existing hardware must be tailored to the specific manufacturer’s equipment being interfaced to. For further information, e-mail NavCom Customer Support at

customersupport@NavComtech.com

Event

The RT-3020M accepts an event input pulse to synchronize external incidents requiring precise GPS time tagging, such as aerial photography. For example, the action of a camera’s aperture creates

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an input pulse to the Event port. The SF-2050M outputs position and time information relative to each photograph taken.

Specifications:

9 50 Ohm input impedance 9 3Vdc > Input Voltage, High < 6Vdc 9 0Vdc < Input Voltage, Low < 1.2Vdc 9 Minimum pulse width, 100nsec 9 Rising or Falling edge Synchronization

Connecting the shared EVT MKR/CAN BUS port requires a five core, 5mm diameter, cable fitted with a LEMO plug, type FGG.0K.305.CLAC50Z, plus strain relief, NavCom P/N 94-310062-3003.

 An event latch interface unit may be

necessary if the input device pulse is unable to drive the input.

Detailed specifications of the Event Input, cable wiring, and configuration may be found in Appendix C of this User Guide.

1 PPS

A pulse is available from the SF-2050M at an output rate of once per second. This pulse can be used for a variety of Time/ Mark applications where relative timing is required.

Specifications:

9 12.5ns relative accuracy 9 Better than 100ns absolute accuracy 9 50 Ohm, TTL level 9 Pulse width, default 100mS, range 10 – 999mS

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9 Pulse delay, default 0mS, range 0 – 999mS 9 Rising or Falling Edge Synchronization

A BNC female connector provides the 1PPS output pulse. A 3ft (0.9m) long, BNC male to BNC male cable (P/N 94-310050-3003) is available from NavCom.

Indicator Panel

Figure 8: RT-3020 Indicator Panel

The indicator panel provides a quick status view of the base radio signal strength (Rover Mode), base station correction type, GPS navigation/operating mode, and the On/Off (I/O) switch, respectively. Each set of indicators has three LEDs.

To power the unit on or off, depress the I/O switch for more than 3 seconds. All LEDs illuminate for a period of 3-5 seconds during power-up of the GPS sensor.

 Link LEDs

 The Link LEDs are software

configurable via the x3f proprietary command. The factory default configuration is Rover Mode. The Link LEDs are not used in Base Mode.

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Table 5: Link LED Indication (Default Rover Mode)

LINK Status

Command Mode

Repeating Red to Amber to Green indicates Searching for base radio signal

C/No - Strong Signal Strength from base radio

C/No - Medium Signal from base radio C/No - Weak Signal Strength from base

radio

 Base LEDs

Table 6: Base Station Indication

BASE Status

The following BASE LEDs reflect the type of RTK corrections when the RT-3020 is operated as a Base Station

RTK/UltraRTK™ - NCT Proprietary

(1Hz blink rate)

CMR (1Hz blink rate)

RTCM 18, 19 (1Hz blink rate)

20, 21 (5Hz blink rate)

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 GPS LEDs

Table 7: GPS Light Indication

GPS Status

Power is off Power is on, No satellites tracked

Tracking satellites, position not available yet Non-differential positioning Code based differential positioning Dual frequency Phase positioning

 The GPS LEDs blink at the PVT

positioning rate (1, 5, 10, or 25Hz)

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Chapter 3 .................................Installation

This chapter provides guidance on hardware installation for optimum performance.

Standard Antenna

The 5/8 inch BSW threaded antenna mount has a depth of 16mm (0.63 inch).

It is possible to remove the 5/8 inch BSW threaded alloy insert to reveal a secondary means of mounting the antenna, a 1-14UNS-2B thread with a depth of 16mm (0.63 inch). This is a typical marine industry mount for navigation antennas.

The BSW insert is secured in-place with an

adhesive, and its removal will change the shock and vibration sustainability characteristics of the antenna mount.

Figure 9: Standard GPS/L-band Antenna

Do not loosen or remove the eight Phillips

screws on the base of the antenna for mounting purposes. This will VOID the warranty and compromise the environmental seal of the antenna, leading to internal damage.

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9 Antenna placement is critical to good system

performance. Avoid antenna shading by buildings, rooftop structures, foliage, hills/mountains, etc.

9 Locate the antenna where it has a clear view of

the sky, to an elevation angle of 7º if possible. Obstructions below 15º elevation generally are not a problem, though this is dependent on satellite availability for the local region.

9 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 satillte shading) will provide poor positioning results. Even 10º of shading can have a negative effect on performance, though this generally is not the case.

9 Avoid placing the antenna on or near metal or

other electrically reflective surfaces.

9 Do not paint the antenna enclosure with a

metallic-based paint.

9 Avoid placing the antenna near electrical motors

(elevator, air conditioner, compressor, etc.)

9 Do not place the antenna too close to other active

antennas. The wavelength of L2 is 0.244m and L1 is 0.19m. The minimum acceptable separation between antennas is 1m (39 in), which provides 6dB of isolation. For 10 dB of isolation, separate the GPS antennas by 2.5m, and for 13dB of isolation (recommended) separate the antennas by 5m.

9 Active antennas (those with LNA’s or amplifiers)

create an electrical field around the antenna. These radiated emissions can interfere with other nearby antennas. Multiple GPS antennas in close

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proximity to each other can create multipath and oscillations between the antennas. These add to position error or the inability to process the satellite signals.

9 Most antenna’s have better gain when the satellite

is high in elevation. Expect tracking performance to fade as the satellite lowers in elevation. It is not unusual to see 10dB difference in antenna gain (which translates into signal strength) throughout the entire elevation tracking path.

9 Map obstructions above the horizon using a

compass and inclinometer. Use satellite prediction software with a recent satellite almanac to assess the impact on satellite visibility at that location (available on NavCom’s web site).

GPS Sensor

Mount the RT-3020 GPS sensor to a flat surface. Shock isolators suitable for 1.8kg (4lbs) may be necessary for environments with high vibration, i.e. Earth moving equipment or aircraft installation.

The RT-3020S can be installed in a backpack for mobile surveying applications.

Do not place the sensor be in a confined space or where it may be exposed to excessive heat, moisture, or humidity.

There are no user serviceable parts

inside the RT-3020 GPS sensor. Removing the screws that secure the front end and rear end plates will void the equipment warranty.

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Figure 10: RT-3020 Base Plate Dimensions

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RT-3020 User Guide – Rev. F

Block Diagram

The RT-3020 has three user configurable physical communications ports (two external and one internal) and several logical communications ports. To aid in distinguishing these ports, please refer to the block diagram below.

Figure 11: RT-3020S/M Block Diagram

 These user configurable physical ports are

Com1, Com2, and Radio/Diagnostic. The Com ports are described in the next section.

 Use StarUtil to configure the internal radio

port as the output port for RTK corrections. Select Port Radio from the NCT RTK dropdown list (see Figure 12). This is the setting also for NCT UltraRTK™. The corrections can be simultaneously sent to any of the logical ports, and also the internal MMC Memory Module for logging. Described in the StarUtil User Guide (see Related Documents in the fore-matter).

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Figure 12: Radio Port Configuration, StarUtil

Communication Port Connectivity

Connect the supplied LEMO 7-Pin connector of the serial cable (P/N 94-310059-3006) to COM 2 (factory default Control Port) of the RT-3020. Connect the DB9 end to the control device.

 Some devices may require an additional

adapter. The receiver is configured as a DCE device.

 COM 2 is the RT-3020 logical control port by

default. COM 1 can be configured as the control port by using the appropriate NavCom proprietary commands or StarUtil. However, there are caveats to Logical / Physical port assignments.

The Control Port is a logical input/output port and can not share the physical port with any other logical port. The Control Port typically handles the most data and requires baud rates in excess of 19.2K baud, particularly in multi-hertz measurement and navigation applications. Though Com 1 is physically

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capable of operating at 115K baud, the throughput from the GPS Engine to the IOP is limited to 19.2K baud (refer to Figure 11). Thus, the recommendation to maintain Com 2 as the Control port for multi-hertz applications.

In the Rover, the NMEA Port is an output logical port and may share the data physical port (non-Control) with RTCM, CMR, or NCT RTK/UltraRTK™ input corrections. In the Base Station, the NMEA port can not share the data port with any RTCM, CMR, or NCT RTK/UltraRTK™ output corrections.

Refer to the Technical Reference Manual for available port configuration settings.

Figure 13: Communication Port Connections

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RT-3020 User Guide – Rev. F

GPS Antenna Connector

The connector used on the RT-3020 is a TNC female, labeled GPS ANT or GPS on the front panel of the sensor as shown in Figure 5.

 The RT-3020 GPS connector provides

4.6 VDC, 50mA max to power the antenna preamplifier. Do not disconnect the antenna when the GPS unit is powered on.

The system is supplied with 12ft (3.6m) of RG58/U cable (P/N 94-310058-3012). The cable is fitted with a right angle male TNC connector and a straight male TNC connector respectively.

The cable length between the antenna and RT-3020 should not exceed 7dB loss at 1.575GHz for optimum performance, though the system may tolerate up to 10dB of cable loss with minimal performance. Lower elevation satellite tracking suffers the most with more than 7dB insertion loss.

Table 8: Acceptable Cable Lengths

Cable

Type

RG-58C 19.605 36.00 7.06 64.32 11.00 7.08 RG-142 16.494 43.00 7.09 54.12 13.00 7.04 RG-213 9.564 74.00 7.08 31.38 22.50 7.06 RG-223 17.224 41.00 7.06 56.51 12.50 7.06 LMR600 3.407 207.00 7.05 11.18 63.00 7.04 LMR400 5.262 133.00 7.00 17.26 41.00 7.08 LMR240 10.127 70.00 7.09 33.23 21.00 6.98 LMR195 14.902 47.00 7.00 48.89 14.00 6.85

Atten.

(dB) per

100 Ft.

Cable Length in Feet

Loss in dB

Atten.

(dB)

per

100 m

Cable

Length

Meters

Loss in dB

In-line amplifiers suitable for all GPS frequencies may be used to increase the length of the antenna cable,

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but care should be exercised that tracking performance is not degraded due to multiple connections, noise from the amplifier, and possible ingress of moisture and dust to the in-line amplifier. In-line amplifier or splitter devices must pass DC power from the receiver to the antenna, or source the appropriate voltage and current to the antenna (see Antenna Specifications). In-line amplifiers may also over-saturate the receiver front-end if improperly used.

 The antenna cable can degrade signal

quality if incorrectly installed, or the cable loss exceeds NavCom specifications. Take care not to kink, stretch, distort, or damage the antenna cable. Do not place the cable adjacent to cables carrying electrical power or radio frequencies. In these instances, attempt to cross cables at 90º angles in an effort to reduce crosscoupling of RF signals.

Where the GPS antenna is exposed to

sources of electromagnetic discharge such as lightning, install a properly grounded in-line electrical surge suppressor between the GPS sensor and antenna. Install protective devices in compliance with local regulatory codes and practices. Protective devices must pass DC power from the receiver to the antenna.

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SSR Antenna Connector

The connector used on the RT-3020 is a BNC female, labeled SSR ANT or SSR on the front panel of the sensor as shown in Figure 5.

 The RT-3020 SSR connector is

passive. It does not provide power.

The system is supplied with 3ft (0.91m) of RG58/U cable (P/N 94-310065-3003). The cable is fitted with a straight male BNC connector and a straight male TNC connector respectively. A 3dB cable loss in the cable length between the antenna and the RT-3020 drops power in half, e.g., 1 W to ½ W.

The RT-3020 complies with FCC

Basics of RTK Surveying

RTK (Real-Time Kinematic) is a GPS system that yields very accurate 3D position fixes immediately in real-time.

A reference station (base station) transmits its GPS position to roving receivers as the receiver generates them. The roving receivers use the reference station readings to differentially correct their own positions. Accuracies of a few centimeters in all three dimensions are possible. RTK requires dual

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frequency GPS receivers and high speed radio modems.

Proper setup of a reference station minimizes GPS errors in the rover. The reference GPS sensor is set up at a known surveyed location. With this position locked in, it transmits its code, clock, and reference station coordinate information to the roving sensor(s). The roving sensor(s) uses this information to correct each GPS measurement it receives.

The RT-3020, configured as a reference station or rover, communicates via the integrated 2-way,

2.4GHz Spread Spectrum Radio (SSR). The SSR was designed specifically for GPS RTK. It has built-in interference rejection to prevent extraneous radio signals from interfering with the reception or transmission of the correction data.

The RT-3020, when configured as a reference station, can transmit corrections to any number of roving receivers capable of picking up the radio signal and decoding one of the three GPS correction formats (NavCom proprietary, RTCM, or CMR). At

2.4Ghz, data broadcast via modulated radio carrier frequency is limited to line of sight for error free reception. The signal can be received in less than ideal environments, though some data loss may occur. The SSR integrated into the RT-3020 provides valid corrections up to a maximum of 10km via RTK or 40km via

UltraRTK™, depending on the fade margin environment in which the equipment is operated.

Setup of the reference station sensor above the roving sensors is recommended to enable transmission to all rovers in all directions with minimal obstruction. High frequency radio signals generally travel a shorter distance than lower frequency signals, and do not penetrate obstructions as well over distance. Figure 14

Requires NCT-2100D Engine

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and Figure 15 illustrate proper and improper RTK reference station installation.

Figure 14: RTK setup – Good Line of Sight

Figure 15: RTK Setup – Poor Line of Sight

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Chapter 4 ...............................Configuration

The RT-3020 has a rich interface and detailed control language, allowing each unit to be individually tailored to a specific application.

There are essentially 3 methods available to configure and control the RT-3020:

9 StarUtil – This program is a NavCom developed

utility designed to configure and view many (but not all) of the RT-3020 functions. In addition to its setup capabilities, StarUtil can capture and log data, upload new software and licenses to the three internal processors, and query and display various receiver performance functions. Though it is developed as an Engineering tool, it has its own place in the commercial market as well. The program is provided on the CD with the RT-3020.

9 3

part controller – Some manufacturers have already integrated NavCom’s control features in their bundled hardware and software solution kits in a variety of applications including GIS, Machine Control, Aerial Photogrammetry, Land & Oceanographic Survey, Agriculture, and Military products. Information on these applications is available from the NavCom web site and customer service.

9 User Program – User’s may develop unique

operating programs to control the RT-3020 (potentially in conjunction with other devices or utilities). To facilitate this effort, NavCom has two additional tools available: the Integrators Tool Kit (ITK) and the Technical Reference Manual (TRM). Information on these tools is available from the NavCom web site and customer service.

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Factory Default Settings

 COM1

9 Configuration - Data port 9 Rate – 19.2Kbps 9 Output of NMEA messages GGA & VTG

scheduled @ 1Hz rate

 Though the output rate defaults to

1Hz, the data output rate can be changed to On Change. Making this selection in the NMEA output list will better reflect the navigation rate selected in the Rover Setup screen.

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Figure 16: StarUtil NMEA Message List

RT-3020 User Guide – Rev. F

Figure 17: StarUtil Rover Navigation Setup

This port is normally used to output data to other devices or machines that can make immediate use of the precise positioning data available from the RT-3020. COM1 also serves as the DGPS correction input/output port when NCT RTK/UltraRTK™, CMR, or RTCM RTK correction services are in use.

 COM2

9 Configuration - Control Port 9 Rate – 19.2Kbps

This port is normally used to input and output proprietary messages used for navigation and receiver setup. Table 9 describes the default messages needed to best initiate surveying with minimal effort.

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The user has full control over the utilized message types and their associated rates via either StarUtil or a third party software/utility.

Table 9: Factory Setup Proprietary Msgs COM 2

Msg Rate Description 44 On Change Almanac 81 On Change Ephemeris 86 On Change Channel Status A0 On Change Alert Message AE 600 Seconds Identification Block B0 On Change Raw Measurement Data B1 On Change PVT Solution

 The term “On Change” indicates that

the RT-3020 will output the specified message only when the information in the message changes. On occasion, there may be an epoch without a message block output.

Message Descriptions

The following message descriptions are fully defined in the Technical Reference Manual (see Related Documents)

9 44 Packed Almanac:

Data corresponding to each satellite in the GPS constellation, including: GPS Week number of collected almanac, GPS Time of week [in seconds] of collected almanac, almanac reference week, almanac reference time, almanac source, almanac health, pages 1-25, and sub-frames 4 and 5.

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9 81 Packed Ephemeris:

Individual satellite tracking information including: GPS Week number of collected ephemeris, GPS Time of week [in seconds] of collected ephemeris, IODC, and sub-frame 1, 2, and 3 data.

9 86 Channel Status:

Receiver channel status information containing: the GPS week, GPS Time of Week, NCT-2100 Engine status, number of satellites viewed/tracked, PDOP, tracked satellite identity, satellite elevation and azimuth, C/No for the L1 and L2 signals, and correction age for each satellite.

9 A0 Alert Text Message:

Details message receipt and processing.

9 AE Identification Block:

Details the receiver software versions (NCT-2000 or NCT-2100, and IOP) and digital serial numbers.

9 B0 Raw Measurement Data:

Raw Measurement Data Block containing: the GPS Week, GPS Time of Week, Time Slew Indicator, Status, Channel Status, CA Pseudorange, L1 Phase, P1-CA Pseudorange, P2-CA Pseudorange, and L2 Phase. This data stream is repeated for each individual tracked satellite.

9 B1 PVT (Position, Velocity, and Time):

Provides: GPS Week number, satellites used, latitude, longitude, navigation mode, and DOP information.

3rd Party Controller Configuration Settings

Please refer to the third party controller solution manual/user guide if your RT-3020 GPS sensor is part of an integrated solution.

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Chapter 5 .................... Safety Instructions

The RT-3020 GPS sensor is designed for precise navigation and positioning using the Global Positioning System. Users must be familiar with the use of portable GPS equipment, the limitations thereof and these safety instructions prior to use of this equipment.

Transport

Always carry the NavCom equipment in its case. The case must be secured during transport to minimize shock and vibration.

Utilize all original packaging when transporting via rail, ship, or air.

RF Exposure Compliance

The RT-3020 complies with FCC exposure limits. Individuals are required to be a minimum of 20 cm (8 in) away from the SSR transmitting antenna when used in the basic configuration. If the transmitting system is modified from the basic setup, check FCC regulations for compliance with exposure limits.

Maintenance

The NavCom equipment may be cleaned using a new lint free cloth moistened with pure alcohol.

Connectors must be inspected, and if necessary cleaned before use. Always use the provided connector protective caps to minimize moisture and dirt ingress.

Inspect cables regularly for kinks and cuts as these may cause interference and equipment failure.

Damp equipment must be dried at a temperature less than +40°C (104°F), but greater than 5°C (41°F) at

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the earliest opportunity.

External Power Source

If the RT-3020 is used with the optional external power cable (P/N 94-310060-3010), it must be connected to the chosen external power solution in accordance with Chapter 2 Interfacing/Electrical Power. It is important that the external power source allow sufficient current draw for proper operation. Insufficient supplied current will cause damage to the external power source.

If your chosen external power source is a disposable battery, please dispose of the battery in accordance with your local regulations.

Safety First

The owner of this equipment must ensure that all users are properly trained prior to using the equipment and are aware of the potential hazards and how to avoid them.

Other manufacturer’s equipment must be used in accordance with the safety instructions issued by that manufacturer. This includes other manufacturer’s equipment that may be attached to NavCom Technology, Inc. manufactured equipment.

Always use the equipment in accordance with local regulatory practices for safety and health at work.

There are no user serviceable parts inside the RT-3020 GPS sensor. Accessing the inside of the equipment will void the equipment warranty.

Take care to ensure the RT-3020 does not come into contact with electrical power installations, the unit is securely fastened and there is protection against electromagnetic discharge in accordance with local regulations.

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A.................... GPS Module Specifications

The technical specifications of this unit are detailed below. NavCom Technology, Inc. is constantly improving, and updating our technology. For the latest technical specifications for all products go to:

http://www.navcomtech.com/Support/

These GPS sensors are fitted with an internal Lithium coin cell battery used to maintain GPS time when power is removed from the unit. This allows faster satellite acquisition upon unit power up. The cell has been designed to meet over 10 years of service life before requiring replacement at a NavCom approved maintenance facility.

Features

9 “All-in-view” tracking with 26 channels

(12 L1 GPS + 12 L2 GPS + 2 SBAS)

9 RTK processing with on-the-fly initialization

9 UltraRTK™ (40km) 9 Fast ambiguity resolution 9 NavCom’s ultra compact RTK format, RTCM,

CMR or CMR+

9 2 separate SBAS channels, RTCA/DO-229D

compliant (WAAS/EGNOS/MSAS/GAGAN)

9 Fully automatic acquisition of satellite broadcast

corrections

9 Rugged and lightweight package for mobile

applications

9 L1 & L2 full wavelength carrier tracking 9 C/A, P1 & P2 code tracking

Requires NCT-2100D Engine

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9 User configurable as base or rover 9 User programmable output rates 9 Integrated Spread Spectrum Radio (SSR) 9 64MB internal memory for data recording 9 Output of NMEA-0183 v3.1 messages 9 Superior interference suppression 9 Patented multipath rejection 9 Self-survey mode (position averaging) 9 CAN bus interface (RT-3020M Only) 9 1PPS Output (RT-3020M Only) 9 Event Marker (RT-3020M Only)

9 TruBlu™ Wireless Connectivity, Bluetooth

compatible

Time-To-First-Fix

Cold Start

Satellite Acquisition

< 60 seconds (typical; with Almanac)

< 5 minutes (typical; without Almanac)

Ambiguity

< 2 seconds (90% of the time)

Resolution Satellite

Reacquisition

< 6 seconds outage time;

immediate reacquisition (< 1 second)

< 30 seconds software, typical; with outage time < 65 seconds

> 65 outage time requires full acquisition process

Requires NCT-2100D Engine

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Dynamics

Acceleration: up to 6g Speed: < 515 m/s* Altitude: < 60,000 ft*

*Restricted by export laws

Measurement Performance

Real-time RTCA/DO-229D Standard SBAS Accuracy (WAAS/EGNOS/MSAS/GAGAN)

Position (H): Position (V): Velocity:

<0.5 m <0.7 m

0.01 m/s

Code Differential GPS <200km (RMS)

Position (H): Position (V): Velocity:

UltraRTK™ Positioning <40km (RMS) (0x5E)

Position (H): Position (V): Velocity:

<12 cm +2ppm <25 cm +2ppm

0.01 m/s

<0.5 cm +1ppm <1.0 cm +1ppm

0.01 m/s

RTK Positioning <10km (RMS) (0x5B)

Position (H): Position (V): Velocity:

<1 cm +1ppm <2 cm +1ppm

0.01 m/s

Pseudo-range Measurement Precision (RMS)

Raw C/A code : Raw carrier phase noise:

Requires GPS software version 4.2 or higher.

20cm @ 42 dB-Hz L1: 0.95 mm @ 42 dB-Hz

L2: 0.85 mm @ 42 dB-Hz

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User programmable output rates

RT-3020S PVT 1, 2, 5Hz Standard

10 & 25Hz Optional

Raw data 1, 2, 5Hz Standard

10, 25, & 50Hz Optional RT-3020M PVT 1, 2, 5, 10Hz Standard

25Hz Optional Raw data 1, 2, 5, 10, 25Hz Standard

50Hz Optional

Data Latency

PVT < 20 ms at all nav rates Raw data < 20 ms at all rates

1PPS

Accuracy: 12.5ns (Relative; User

Configurable); (RT-3020M Only)

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Built-in Radio Performance1

Frequency Band: 2.400GHz - 2.485GHz Modulation: Frequency Hopping Spread

Spectrum

Data Rate: 9600bps (configurable) Transmit Power:2 1-Watt max Receiver

Sensitivity:

-105dBm

Range @ Max. Power (36dBm

10km (6.2 miles) Line of Sight

EIRP): Maximum EIRP: 36dBm3

Subject to Country Licensing

EIRP and hopping bandwidth restrictions vary depending on local regions. Contact NavCom Technology, Inc. for regulations in your local area.

Using high gain antenna. High gain antenna’s are available from www.antenex.com

; MHA range utilizing 2.4 GHz, 8dB, gain antenna.

Connector Assignments

Data Interfaces:

2 serial ports from 1200 bps to 115.2 kbps CAN Bus I/F RT-3020M Only Event Marker

RT-3020M Only

I/P 1PPS RT-3020M Only

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Input/Output Data Messages

NCT Proprietary Data

NMEA-0183 Messages

(Output Only) Proprietary

NMEA-0183 Type (Output Only)

Code Corrections RTCM 1 or 9

RTK Correction Data (I/O)

PVT , Raw Measurement Satellite Messages Nav Quality Receiver Commands

ALM, GBS, GGA, GLL, GSA, GST, GSV, RMC, VTG, ZDA

SET

WAAS/EGNOS/MSAS/GAGAN NCT Proprietary RTCM 18,19 or 20, 21

CMR+/CMR (Msg. 0, 1, 2)

 See Related Standards at the front of

this manual for information on the various data formats

LED Display Functions (Default)

Link Base Station

GPS

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Base Radio Signal (Rover Mode) Type of Correction/Rate (Base Mode)

Position Quality

RT-3020 User Guide – Rev. F

Satellite Based Augmentation System Signals

RTCA/DO-229D Standard (WAAS/EGNOS/MSAS/GAGAN)

Physical and 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: SSR Antenna: GPS Antenna: CAN bus + Event: 1PPS Output:

Antenna Power 4.6 VDC, 50mA max bias for

Temperature (ambient)

Operating Storage:

Humidity: 95% non-condensing

10 VDC to 30 VDC 5 W

2 x 7 pin Lemo 4 pin Lemo BNC TNC-F 5 pin Lemo (RT-3020M only) BNC (RT-3020M only)

LNA

-40º C to +55º C

-40º C to +85º C

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RT-3020 User Guide – Rev. F

B........................... Antenna Specifications

Table 10: Standard Antenna

Part Number 82-001002-3002 Frequency 1525-1585 MHz

GPS L1 plus INMARSAT StarFire™

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

≤ 2.0:1 / 9.54 dB min.

60mA +

-55°C to +85°C

stable

10mA @ 5VDC

 NavCom P/N 82-001002-3001 is an

optional aircraft mount antenna, also rated to 70,000 feet (21,336m).

 Designed to DO-160D Standard

StarFire™ is not applicable to the RT-3020.

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Figure 18: PN: 82-001002-3002 Antenna Dimensions

 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 our web site:

http://www.navcomtech.com/Support/Dow nloadCenter.cfm?category=antenna

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Radiation Pattern

24º

RT-3020 User Guide – Rev. F

6.5dB @ 90º

32º

-4dB @ 5º

0dB

07-00008-A

-4.5dB @ 5º

0dB

Figure 19: AN-2004T Radiation Pattern

Optimal antenna performance is realized at elevations 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)

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Table 11: SSR Antenna (with mount)

Part Number 91-310020-3001 Frequency 2.4 GHz Polarization Vertical Impedance 50 ohms VSWR / RL < 2.0:1 / 9.54 dB RF Power Handling 10 Watts Cable Connector TNC Operating Temp Finish

-20°C to +65°C Polyurethane

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Figure 20: PN: 82-001002-3001 Antenna Dimensions

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C ...................... Event Input Configuration

Figure 21 details the wiring of the Event/Can cable assembly (NavCom P/N 94-310062-3003).

Refer to Chapter 2 Interfacing/Event for detailed electrical specifications.

Table 12 details the wiring configuration required for Event-Hi, and Event-Lo pulse sensing.

Figure 21: Event Cable Wiring Diagram

Table 12: Event Wiring Connections

Pin #

1 Event-Lo Tie Event-Hi to Ground 2 Event-Hi Tie Event-Lo to Ground 3 Ground N/A

Once the cable is wired to correspond with the event pulse requirements, configure the receiver to output the message containing a time mark, referenced to the time kept within the receiver, indicating when the event is sensed (xB4).

The Event Input can be triggered on the Rising or Falling edge of the input pulse. Configuration is possible thru the StarUtil program. Select Receiver > Setup > PPS and Event Latch from the menu bar.

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Signal

Name

Event Sync Wiring

RT-3020 User Guide – Rev. F

The PPS and Event Latch window opens (see Figure 22).

Figure 22: PPS & Event Latch Configuration

In StarUtil, enable the Event Latch message (0xB4) in the NCT Binary Messages output list. Select Receiver > Messages > NCT output from the menu bar to open the list. Set the Message Rate for 0xB4 to On Trigger. Right-Click in the Rate cell for message B4. Select Other > On Trigger from the menu (see Figure 23). Once configured, the Event Latch Message (0xB4) is output upon recognition of an input trigger by the receiver.

 Message 0xB4 is described in the

Technical Reference Manual (see Related Documents in the fore-matter).

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Figure 23: Event Latch Output Rate

RT-3020 User Guide – Rev. F

Glossary

.yym files see meteorological 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).

almanac files an almanac file contains orbit information, clock corrections, and atmospheric delay parameters for all satellites tracked. It is transmitted to a receiver from a satellite and is used by mission planning software.

alt see altitude. altitude 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 height above mean sea level (MSL).

Antenna Phase Center (APC) 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.

APC see antenna phase center or phase center. Autonomous positioning (GPS) 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

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GPS receiver can perform, yielding position fixes that are precise to 100 meters with Selective Availability on, and 30 meters with S/A off.

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.

base station see reference station. baud rate (bits per second) the number of bits sent

or received each second. For example, a baud rate of 9600 means there is a data flow of 9600 bits each second. One character roughly equals 10 bits.

bits per second see baud rate. bps see baud rate. BSW (British Standard Whitworth) a type of coarse

screw thread. A 5/8” diameter BSW is the standard mount for survey instruments.

C/A code see Coarse Acquisition code. CAN BUS a balanced (differential) 2-wire interface

that uses an asynchronous transmission scheme. Often used for communications in vehicular applications.

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

civilian code see Coarse Acquisition code. Coarse Acquisition code (C/A or Civilian code)

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

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COM# 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) a standard format for DGPS corrections used to transmit corrections from a reference station to rover sensors. See Related Standards in Notices.

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

convergence period (StarFire™) is the time necessary for the received StarFire™ signal corrections to be applied and the position filtered to optimal performance. The convergence period is typically 30 to 45 minutes to achieve <decimeter accuracy. This period may be overcome using the Quick Start method.

data files files that contain Proprietary, GPS, NMEA, RTCM, or any type of data logged from a GPS receiver.

datum A reference datum is a known and constant surface which can be used to describe the location of unknown points. Geodetic datums define the size and shape of the earth and the origin and orientation of the coordinate systems used to map the earth.

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 Communications Equipment. Defined pin assignments based on the IEEE RS-232 signaling standard. See the Figure G-1:

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Modem

DTE

DB25RJ45 DB9DB9 DB25 6 5

4 2 3

1 8

4 5

Straight-Through Cable

DCD

RD TD

DTR GND DSR

RTS

CTS

DCE

1 2 3 4 5 6 7 8

07-00041-A

8 3 2

7 6 4 5

Figure 24: DTE to DCE RS-232 Pin Assignments

DGPS see Differential GPS. Differential GPS (DGPS) a positioning procedure

that uses two receivers, a rover 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) 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 DOPs to measure different components of the error. Note: this is a unitless value. see also PDOP.

DOP see Dilution of Precision. DTE Data Terminal Equipment. See DCE.

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dual-frequency a type of GPS receiver that uses both L1 and L2 signals from GPS satellites. A dualfrequency receiver can compute more precise position fixes over longer distances and under more adverse conditions because it compensates for ionospheric delays. The SF-2050 is a dual frequency receiver.

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.

EGNOS (European Geostationary Navigation Overlay Service) a European satellite system used

to augment the two military satellite navigation systems now operating, the US GPS and Russian GLONASS systems.

elevation 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 a mathematical figure approximating the earth’s surface, generated by rotating an ellipse on its minor axis. GPS positions are computed relative to the WGS-84 ellipsoid. 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.

epoch literally a period of time. This period of time is defined by the length of the said period.

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GAGAN (GPS Aided Geo Augmented Navigation)

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.

geoid 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 measured relative to an ellipsoid. Conventionally surveyed positions reference a geoid. More accurate GPS readings can be obtained by calculating the distance between the geoid and ellipsoid at each position and subtracting this from the GPS altitude measurement.

GIS (Geographical Information Systems) 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 correct distance from each of four known points. GPS measures the distance from a point to at least four satellites from a constellation of 24 NAVSTAR satellites orbiting the earth at a very high altitude. These distances are used to calculate the point’s position.

GMT see Greenwich Mean Time. GPS see Global Positioning System. GPS time a measure of time. GPS time is based on

UTC, but does not add periodic ‘leap seconds’ to

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RT-3020 User Guide – Rev. F

correct for changes in the earth’s period of rotation. As of September 2002 GPS time is 13 seconds ahead of UTC.

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

HAE see altitude, and ellipsoid. IODC Issue of Data, Clock - The IODC indicates the

issue number of the data set and thereby 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.

JPL Jet Propulsion Laboratory. Kbps kilobits per second. L-Band the group of radio frequencies extending

from approximately 400MHz to approximately 1600MHz. The GPS carrier frequencies L1 (1575.4MHz) and L2 (1227.6 MHz) are in the L-Band range.

L1 carrier frequency 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, and a 50 bit/second navigation message. The bandwidth of this signal is

1.023MHz. L2 carrier frequency the secondary L-Band carrier

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

lat see latitude. latitude (lat) the north/south component of the

coordinate of a point on the surface on the earth; expressed in angular measurement from the plane of

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the equator to a line from the center of the earth to the point of interest. Often abbreviated as Lat.

LED acronym for Light Emitting Diode. LEMO a type of data or power connector. LES Land Earth Station the point on the earth’s

surface where data is up linked to a satellite. logging interval the frequency at which positions

generated by the receiver are logged to data files.

lon see longitude. longitude (long) 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 Long.

Mean Sea Level (MSL) a vertical surface that represents sea level.

meridian one of the lines joining the north and south poles at right angles to the equator, designated by degrees of longitude, from 0° at Greenwich to 180°.

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.

MSAS (MTSAT Satellite-based Augmentation System) 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.

MSL see Mean Sea Level.

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multipath error 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 (.YYn) 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 navigation file contains satellite position and time information.

observation (.YYo) 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. An observation file contains raw GPS position information.

P/N Part Number. P-code the extremely long pseudo-random code

generated by a GPS satellite. It is intended for use only by the U.S. military, so it can be encrypted to Ycode deny unauthorized users access.

parity 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).

PDA Personal Digital Assistant. PDOP see Position Dilution of Precision. PDOP mask the highest PDOP value at which a

receiver computes positions. phase center 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

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RT-3020 User Guide – Rev. F

of the antenna mount, to the known distance between this point and the phase center.

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

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

Post-processing 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 you have collected the data and returned to the office, rather than in real time as you log the data, so it can use complex, calculations to achieve greater accuracy.

Precise code see P-code. PRN (Uppercase) typically indicates a GPS satellite

number sequence from 1 – 32. prn (Lower Case) see Pseudorandom Noise. Protected code see P-code. Proprietary commands those messages sent to and

received from GPS equipment produced by NavCom Technology, Inc. own copyrighted binary language.

pseudo-random noise (prn) a sequence of data that appears to be randomly distributed 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 the apparent distance from the reference station’s antenna to a satellite, calculated

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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.

PVT GPS information depicting Position, Velocity, Time in the NCT proprietary message format.

Quick Start (StarFire™) a startup mode that allows instant <decimeter accuracy with received StarFire™ signals, allowing the convergence period to be waived. The Quick Start (user input) position should have an accuracy of better <decimeter to achieve maximum results. Any error in the user input position will bias the StarFire™ position error accordingly, until convergence can correct the bias. In this scenario, convergence may take longer than the typical startup convergence period.

Radio Technical Commission for Maritime Services see RTCM.

range 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 least four GPS satellites. Geometrically, there can only be one point in space, which is the correct distance from each of four known points.

RCP a NavCom Technology, Inc. proprietary processing technique in which carrier phase measurements, free of Ionospheric and Troposphere effects are used for navigation.

Real-Time Kinematic (RTK) a GPS system that yields very accurate 3D position fixes immediately in

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real-time. The base station transmits its GPS position to roving receivers as the receiver generates them, and the roving receivers use the base station readings to differentially correct their own positions. Accuracies of a few centimeters in all three dimensions are possible. RTK requires dual frequency GPS receivers and high speed radio modems.

reference station a reference station collects GPS data for a fixed, known location. Some of 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 collected by roving receivers.

RHCP Right Hand Circular Polarization used to discriminate satellite signals. GPS signals are RHCP.

RINEX (Receiver Independent Exchange) is a file set of standard definitions and formats 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:

the observation (.YYo) file, the navigation (.YYn) file, meteorological (.YYm) files; where YY indicates

the last two digits of the year the data was collected.

rover 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 such as StarFire™.

roving receiver see rover.

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RTCM (Radio Technical Commission for Maritime Services) a standard format 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.

RTK see Real-time kinematic. RTG Real Time GIPSY, a processing technique

developed by NASA’s Jet Propulsion Laboratory to provide a single set of real time global corrections for the GPS satellites.

S/A see Selective Availability. SBAS (Satellite Based Augmentation System) this

is a more general term, which encompasses StarFire™, WAAS, EGNOS, MSAS, and GAGAN type corrections.

Selective Availability (S/A) is the deliberate degradation of the GPS signal by encrypting the Pcode 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-frequency is a type of receiver that only uses the L1 GPS signal. There is no compensation for ionospheric effects.

SNR see signal-to-noise Ratio. StarFire™ a set of real-time global orbit and clock

corrections for GPS satellites. StarFire™ equipped receivers are capable of real-time decimeter positioning.

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Spread Spectrum Radio (SSR) a radio that uses wide band, noise like (pseudo-noise) signals that are hard to detect, intercept, jam, or demodulate making any data transmitted 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.

SV (Space Vehicle) a GPS satellite. 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.

UTC see Universal Time Coordinated. WAAS (Wide Area Augmentation System) a US

satellite system that provides a set of corrections for the GPS satellites, which are valid for the North American region. They incorporate satellite orbit and clock corrections.

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

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

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

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NavCom RT-3020 User Manual Rev.F

Specifications and Main Features

Frequently Asked Questions

User Manual

Table of Contents

List of Figures

List of Tables

Notices

Copyright

Trademarks

FCC Notice

User Notice

Limited Warranty

StarFire™ Licensing

USG FAR

Global Positioning System

Revision History

Use of this Document

Related Documents

StarUtil User Guide P/N 96-310008-3001

Technical Reference Manual P/N 96-3120001-3001

RINEXUtil User Guide P/N 96-310021-2101

Integrators Toolkit P/N 97-310020-3001

NavCom Release Notes

Related Standards

ICD-GPS-200

RTCM-SC-104

CMR, CMR+

NMEA-0183

Publicly-Operated SBAS Signals

RTCA/DO-229D

WAAS (Wide Area Augmentation System)

EGNOS (European Geostationary Navigation Overlay Service)

MSAS (MTSAT Satellite-based Augmentation System)

GAGAN (GPS Aided Geo Augmented Navigation)

System Overview

GPS Sensor System

Accuracy

NCT Binary Proprietary Data

NMEA-0183 Data

Models

RT-3020S

RT-3020M

Antennae

Standard

Spread Spectrum Radio Antenna

Airborne (option)

Controller

Applications

Unique Features

Electrical Power

Communication Ports

CAN Bus/Event

Event

1 PPS

Indicator Panel

Standard Antenna

GPS Sensor

Block Diagram

Communication Port Connectivity

GPS Antenna Connector

SSR Antenna Connector

Basics of RTK Surveying

Factory Default Settings

Message Descriptions

3rd Party Controller Configuration Settings

Transport

RF Exposure Compliance

Maintenance

External Power Source

Safety First

Features

Time-To-First-Fix

Dynamics

Measurement Performance

User programmable output rates

Data Latency

1PPS

Built-in Radio Performance1

Connector Assignments