Satellite Navigation
Digital Standards for
R&S®SMBV100A
Operating Manual
(;×>K<)
1173142712
Version 14
Operating Manual
This document describes the software options for satellite navigation: GPS, Assisted GPS, GPS P-Code,
Galileo, Assisted Galileo, GLONASS, Assisted GLONASS, COMPASS/BeiDou, QZSS L1 C/A, SBAS,
Enh. GNSS and GNSS Extensions, incl. Extension to 12 and 24 Satellites, Obscuration Simulation and
Automatic Multipath, Antenna Pattern, Spinning and Attitude Simulation
Described are the following software options:
●
R&S®SMBV-K44/-K65/-K66/-K67/-K91/-K92/-K93/-K94/-K95/-K96/-K101/-K102/-K103/-K105/-K107/K110
1415.8060.xx, 1415.8560.xx, 1415.8683.xx, 1419.2509.xx, 1415.8577.xx, 1415.8583.xx,
1415.8660.xx, 1415.8677.xx, 1419.2521.xx, 1415.8790.xx, 1415.8802.xx, 1415.8819.xx,
1415.8825.xx, 1419.2350.02, 1419.2709.xx, 1419.2273.xx
This manual describes firmware version 4.70.108.xx and later of the R&S®SMBV100A.
© 2020 Rohde & Schwarz GmbH & Co. KG
Mühldorfstr. 15, 81671 München, Germany
Phone: +49 89 41 29 - 0
Fax: +49 89 41 29 12 164
Email: info@rohde-schwarz.com
Internet: www.rohde-schwarz.com
Subject to change – Data without tolerance limits is not binding.
R&S® is a registered trademark of Rohde & Schwarz GmbH & Co. KG.
Trade names are trademarks of the owners.
1173.1427.12 | Version 14 | Satellite Navigation
The following abbreviations are used throughout this manual: R&S®SMBV100A is abbreviated as R&S SMBV, R&S®WinIQSIM2TM is
abbreviated as R&S WinIQSIM2
ContentsSatellite Navigation
Contents
1 Preface.................................................................................................. 11
1.1 About This Manual...................................................................................................... 11
1.2 Documentation Overview........................................................................................... 12
1.2.1 Quick Start Guide Manual............................................................................................. 12
1.2.2 Operating Manual and Help.......................................................................................... 12
1.2.3 Service Manual............................................................................................................. 12
1.2.4 Instrument Security Procedures....................................................................................13
1.2.5 Basic Safety Instructions...............................................................................................13
1.2.6 Data Sheets and Brochures.......................................................................................... 13
1.2.7 Release Notes and Open Source Acknowledgment (OSA).......................................... 13
1.2.8 Application Notes, Application Cards, White Papers, etc..............................................13
2 Welcome to the GNSS Satellite Navigation Standards.....................14
2.1 Accessing the GNSS Dialog.......................................................................................15
2.2 Scope........................................................................................................................... 15
3 About the GNSS Options.....................................................................16
3.1 Overview of the Basic Real-Time GNSS Options.....................................................18
3.1.1 Real-time Generation.................................................................................................... 19
3.1.2 Multi-satellite GNSS Signal........................................................................................... 19
3.1.3 GNSS System Configurations.......................................................................................21
3.1.4 Signal Dynamics........................................................................................................... 21
3.1.5 Modulation Control........................................................................................................ 21
3.1.6 Multiple Almanacs......................................................................................................... 21
3.1.7 On-the-fly Configuration of the Satellites Constellation.................................................22
3.1.8 Signal Generation with Projection of the Ephemeris Navigation Data.......................... 22
3.1.9 Dynamic Exchange of Satellites....................................................................................23
3.1.10 Flexible Power Configuration and Automatic Dynamic Power Control......................... 23
3.1.11 Simulation of Uninterrupted Location Fix...................................................................... 24
3.1.12 Real-Time S.P.O.T. Display........................................................................................... 25
3.2 GPS P-Code (R&S SMBV-K93)...................................................................................25
3.3 Enhancements of Assisted GNSS Options GPS, Galileo and GLONASS..............25
3.3.1 Support of RINEX Files................................................................................................. 26
3Operating Manual 1173.1427.12 ─ 14
ContentsSatellite Navigation
3.3.2 Predefined Test Scenarios as Basis for A-GNSS Protocol and Conformance Testing
...................................................................................................................................... 26
3.3.3 Custom Build Scenarios................................................................................................26
3.3.4 Generation of Assistance Data..................................................................................... 27
3.4 Extension to 12 / 24 Satellites (R&S SMBV-K91/-K96).............................................27
3.5 Functional Overview of Option GNSS Enhanced (R&S SMBV-K92).......................28
3.5.1 Moving Scenarios..........................................................................................................28
3.5.2 Static Multipath Signal Generation................................................................................29
3.5.3 Configuration of the Atmospheric Parameters.............................................................. 29
3.5.4 Time Conversion Configuration.....................................................................................30
3.5.5 Leap Second Simulation............................................................................................... 30
3.5.6 Internal Waypoint Resampling...................................................................................... 30
3.5.7 Motion Smoothening Using Vehicle Description File.....................................................30
3.5.8 Hardware in the Loop (HIL)...........................................................................................31
3.5.8.1 Tips for Best Results..................................................................................................... 32
3.5.8.2 HIL Commands............................................................................................................. 33
3.5.8.3 Synchronization.............................................................................................................34
3.5.8.4 System Latency.............................................................................................................34
3.5.8.5 Latency Calibration....................................................................................................... 35
3.5.8.6 Adding a Constant Delay to Compensate for Command Jitter..................................... 36
3.5.8.7 Interpolation.................................................................................................................. 37
3.5.8.8 Trajectory Prediction..................................................................................................... 38
3.6 GNSS Extension for Obscuration Simulation and Automatic Multipath
(R&S SMBV-K101)....................................................................................................... 39
3.7 GNSS Extension for Antenna Pattern (R&S SMBV-K102)....................................... 40
3.8 GNSS Extension for Spinning and Attitude Simulation (R&S SMBV-K103).......... 43
3.9 Functional Overview of Option Differential GPS (R&S SMBV-K110)...................... 44
3.9.1 File Conversion Tool......................................................................................................44
3.9.2 SBAS Configuration...................................................................................................... 45
3.9.3 Improving the Simulation Accuracy, Simulation of SV Perturbation and Errors............ 47
4 GNSS Configuration and Settings......................................................50
4.1 GNSS Main Dialog.......................................................................................................50
4.1.1 General Settings for GNSS Simulation......................................................................... 51
4.1.2 User Environment......................................................................................................... 56
4Operating Manual 1173.1427.12 ─ 14
ContentsSatellite Navigation
4.1.3 Navigation Data.............................................................................................................58
4.1.4 Advanced Configuration................................................................................................62
4.2 GNSS System Configuration Settings...................................................................... 62
4.3 Localization Data Settings......................................................................................... 65
4.4 Obscuration and Auto Multipath Settings................................................................ 71
4.4.1 Common Settings..........................................................................................................71
4.4.2 Vertical Obstacles Settings........................................................................................... 74
4.4.3 Roadside Planes Settings............................................................................................. 78
4.4.4 Full Obscuration Settings.............................................................................................. 81
4.4.5 Ground/Sea Reflection..................................................................................................82
4.4.6 Land Mobile Multipath................................................................................................... 84
4.5 Antenna Pattern/Body Mask Settings....................................................................... 88
4.6 Time Conversion Configuration Settings................................................................. 91
4.7 GNSS/RNSS Configuration Settings......................................................................... 94
4.8 File Conversion Tool Settings....................................................................................96
4.9 SBAS Configuration Settings.................................................................................... 99
4.9.1 SBAS General Settings...............................................................................................100
4.9.2 Timing Setting............................................................................................................. 102
4.9.3 Almanac Configuration................................................................................................105
4.9.4 RINEX File Configuration............................................................................................ 107
4.9.5 Ionospheric Grid File Configuration.............................................................................108
4.9.6 PRN Mask File Configuration...................................................................................... 110
4.9.7 Fast Correction File Configuration...............................................................................111
4.9.8 Long Term Correction File Configuration.....................................................................113
4.9.9 Fast Correction Degradation Factor Configuration......................................................115
4.9.10 Clock-Ephemeris Covariance Matrix Configuration.....................................................116
4.9.11 Service Configuration.................................................................................................. 117
4.9.12 Degradation Factors Configuration..............................................................................118
4.9.13 Visualizing the Parameters Variation Over Time.........................................................120
4.9.14 EGNOS and WAAS Navigation Data as Raw Files.....................................................122
4.10 Satellite Configuration Settings...............................................................................124
4.10.1 Power Configuration....................................................................................................125
4.10.2 General Satellites Settings..........................................................................................133
5Operating Manual 1173.1427.12 ─ 14
ContentsSatellite Navigation
4.10.3 Configuration of the Satellite Constellation................................................................. 137
4.10.4 Individual Satellite Settings......................................................................................... 139
4.10.5 Modulation Control...................................................................................................... 144
4.10.6 Signal Dynamics......................................................................................................... 145
4.10.7 Global Signal Configuration........................................................................................ 148
4.10.8 Satellites Power Tuning...............................................................................................150
4.10.9 Navigation Message Configuration............................................................................. 152
4.10.10 Static Multipath Configuration..................................................................................... 163
4.11 Atmospheric Configuration Settings...................................................................... 165
4.12 Real-Time S.P.O.T. Settings......................................................................................174
4.12.1 Display Type................................................................................................................179
4.12.2 Real-Time Information.................................................................................................179
4.12.3 Reference Location..................................................................................................... 180
4.12.4 Trajectory View Settings..............................................................................................181
4.13 Data Logging Settings.............................................................................................. 182
4.13.1 Data Logging General Settings................................................................................... 184
4.13.2 Configure Logging Settings.........................................................................................188
4.14 Assistance Data Generation Settings..................................................................... 193
4.15 Trigger/Marker/Clock Settings................................................................................. 203
4.15.1 Trigger In.....................................................................................................................204
4.15.2 Marker Settings........................................................................................................... 207
4.15.3 Clock Settings............................................................................................................. 209
4.15.4 Global Settings............................................................................................................210
5 How to Perform Signal Generation Tasks with the GNSS Options
............................................................................................................. 211
5.1 Generating a GNSS Signal for Simple Receiver Tests (Static Mode)................... 213
5.2 Generating a GNSS Signal with Automatic Exchange of the Satellites...............213
5.3 Generating a GNSS Signal with Manual Exchange of the Satellites.................... 214
5.4 Generating a QZSS Test Signal................................................................................215
5.5 Generating A-GPS Custom Build Scenarios.......................................................... 215
5.6 Generating an A-GPS Test Signal............................................................................216
5.7 Generating an A-GNSS Test Signal......................................................................... 217
5.8 Generating a GNSS Assistance Data...................................................................... 217
6Operating Manual 1173.1427.12 ─ 14
ContentsSatellite Navigation
5.9 Creating Multipath Scenarios.................................................................................. 218
5.10 Generating a GPS Signal Modulated with P Code................................................. 222
5.11 Configuring the Navigation Parameters................................................................. 223
5.12 Adjusting the Power Settings.................................................................................. 224
5.13 Generating a GNSS Signal for Receiver Sensitivity Tests.................................... 225
5.14 Handling NMEA Files................................................................................................ 227
5.15 Creating GNSS Scenarios in a User Environment................................................. 227
5.16 Visualizing the Effect of an Antenna Pattern..........................................................232
5.17 Creating and Modifying Antenna Patterns and Body Masks................................ 235
5.18 Using the File Conversion Tool................................................................................239
5.19 Using the SBAS Settings..........................................................................................243
5.20 Simulating SV Perturbations and Errors................................................................ 247
5.21 Generating GNSS Signal with Several Instruments...............................................254
6 Remote-Control Commands............................................................. 257
6.1 Programming Examples........................................................................................... 259
6.2 Primary Settings........................................................................................................259
6.3 GNSS System Configuration....................................................................................267
6.4 User Environment, Antenna Pattern and Body Mask............................................ 270
6.5 Localization Data.......................................................................................................274
6.6 Navigation Data......................................................................................................... 280
6.7 Obscuration and Auto Multipath..............................................................................283
6.8 Hardware in the Loop (HIL)...................................................................................... 294
6.9 Almanac / RINEX Configuration...............................................................................302
6.10 Time Conversion Configuration...............................................................................309
6.11 SBAS Configuration..................................................................................................315
6.12 Static Multipath Configuration.................................................................................327
6.13 Satellites Configuration and Satellites Signal Settings.........................................331
6.14 Modulation Control................................................................................................... 342
6.15 Signal Dynamics....................................................................................................... 344
6.16 Global Signal Configuration.....................................................................................348
6.17 Power Tuning and Power Settings.......................................................................... 349
6.18 Navigation Message Configuration......................................................................... 355
6.19 Atmospheric Configuration......................................................................................378
7Operating Manual 1173.1427.12 ─ 14
ContentsSatellite Navigation
6.20 Assistance Data Settings......................................................................................... 383
6.21 S.P.O.T Configuration and Real-Time Commands................................................. 399
6.22 Data Logging............................................................................................................. 417
6.23 Trigger Settings.........................................................................................................426
6.24 Marker Settings......................................................................................................... 430
6.25 Clock Settings........................................................................................................... 432
Annex.................................................................................................. 435
A User Environment Files.....................................................................435
A.1 Movement or Motion Files........................................................................................435
A.1.1 Waypoint File Format.................................................................................................. 435
A.1.2 Vector Trajectory File Format......................................................................................436
A.1.3 NMEA Files as Source for Movement Information...................................................... 439
A.1.4 Trajectory Description Files.........................................................................................439
A.1.5 Resampling Principle.................................................................................................. 443
A.1.6 Calculating the Maximum Time Duration of a Movement File.....................................444
A.2 Vehicle Description Files (Used for Smoothening)................................................445
A.3 Antenna Pattern and Body Mask Files....................................................................446
A.4 Land Mobile Multipath (LMM) Files..........................................................................448
B RINEX Files.........................................................................................450
B.1 RINEX Format Description....................................................................................... 450
B.2 Example of a RINEX File...........................................................................................451
C NMEA Scenarios................................................................................ 453
D SBAS Message Files Format.............................................................455
D.1 SBAS Message Files Extracts..................................................................................455
D.2 Interpolation and Correction Data Sampling Principle..........................................459
E Channel Budget..................................................................................461
F QZSS Navigation Message Scheduling........................................... 464
G List of Predefined Test Scenarios.................................................... 465
H List of Predefined Files......................................................................471
8Operating Manual 1173.1427.12 ─ 14
ContentsSatellite Navigation
Glossary: List of Publications with Further or Reference Informa-
tion.......................................................................................................478
List of Commands..............................................................................480
Index....................................................................................................501
9Operating Manual 1173.1427.12 ─ 14
ContentsSatellite Navigation
10Operating Manual 1173.1427.12 ─ 14
1 Preface
1.1 About This Manual
This operating manual provides all the information specific to the GNSS options. All
general instrument functions and settings common to all applications and operating
modes are described in the main R&S SMBV operating manual.
The main focus in this manual is on the provided settings and the tasks required to
generate a signal. The following topics are included:
●
Welcome to the GNSS options R&S SMBV-K44/-K66/-K94/-K105/-K107/-K110
Introduction to and getting familiar with the options
●
About the GNSS options
Background information on basic terms and principles in the context of GNSS signal generation
●
GNSS configuration and settings
A concise description of all functions and settings available to configure signal generation with their corresponding remote control command
●
How to perform typical signal generation tasks with the GNSS options
The basic procedure to perform signal generation tasks and step-by-step instructions for more complex tasks or alternative methods
And detailed examples to guide you through typical signal generation scenarios
and allow you to try out the application immediately
●
Remote control commands
Remote commands required to configure and perform signal generation in a
remote environment, sorted by tasks
(Commands required to set up the instrument or to perform common tasks on the
instrument are provided in the main R&S SMBV operating manual)
Programming examples demonstrate the use of many commands and can usually
be executed directly for test purposes
●
Annex
Reference material such as description of file formats, extensive lists, and tables
●
List of remote commands
Alphabetical list of all remote commands described in the manual
●
Index
PrefaceSatellite Navigation
About This Manual
Contents and scope
This description assumes R&S SMBV equipped with all available options. Depending
on your model and the installed options, some of the functions may not be available on
your instrument.
Notes on screenshots
When describing the functions of the product, we use sample screenshots. These
screenshots are meant to illustrate as much as possible of the provided functions and
11Operating Manual 1173.1427.12 ─ 14
possible interdependencies between parameters. The shown values may not represent
realistic usage scenarios.
The screenshots usually show a fully equipped product, that is: with all options installed. Thus, some functions shown in the screenshots may not be available in your particular product configuration.
1.2 Documentation Overview
This section provides an overview of the R&S SMBV user documentation. Unless
specified otherwise, you find the documents on the R&S SMBV product page at:
www.rohde-schwarz.com/manual/smbv100a
1.2.1 Quick Start Guide Manual
Introduces the R&S SMBV and describes how to set up and start working with the
product. Includes basic operations, typical measurement examples, and general information, e.g. safety instructions, etc. A printed version is delivered with the instrument.
PrefaceSatellite Navigation
Documentation Overview
1.2.2 Operating Manual and Help
Separate manuals for the base unit and the software options are provided for download:
●
Base unit manual
Contains the description of all instrument modes and functions. It also provides an
introduction to remote control, a complete description of the remote control commands with programming examples, and information on maintenance, instrument
interfaces and error messages. Includes the contents of the quick start guide manual.
●
Software option manual
Contains the description of the specific functions of an option. Basic information on
operating the R&S SMBV is not included.
The contents of the user manuals are available as help in the R&S SMBV. The help
offers quick, context-sensitive access to the complete information for the base unit and
the software options.
All user manuals are also available for download or for immediate display on the Internet.
1.2.3 Service Manual
Describes the performance test for checking the rated specifications, module replacement and repair, firmware update, troubleshooting and fault elimination, and contains
mechanical drawings and spare part lists.
12Operating Manual 1173.1427.12 ─ 14
The service manual is available for registered users on the global Rohde & Schwarz
information system (GLORIS, https://gloris.rohde-schwarz.com).
1.2.4 Instrument Security Procedures
Deals with security issues when working with the R&S SMBV in secure areas. It is
available for download on the Internet.
1.2.5 Basic Safety Instructions
Contains safety instructions, operating conditions and further important information.
The printed document is delivered with the instrument.
1.2.6 Data Sheets and Brochures
The data sheet contains the technical specifications of the R&S SMBV. It also lists the
options and their order numbers and optional accessories.
PrefaceSatellite Navigation
Documentation Overview
The brochure provides an overview of the instrument and deals with the specific characteristics.
See www.rohde-schwarz.com/brochure-datasheet/smbv100a
1.2.7 Release Notes and Open Source Acknowledgment (OSA)
The release notes list new features, improvements and known issues of the current
firmware version, and describe the firmware installation.
The open source acknowledgment document provides verbatim license texts of the
used open source software.
See www.rohde-schwarz.com/firmware/smbv100a
1.2.8 Application Notes, Application Cards, White Papers, etc.
These documents deal with special applications or background information on particular topics.
See www.rohde-schwarz.com/application/smbv100a.
13Operating Manual 1173.1427.12 ─ 14
Welcome to the GNSS Satellite Navigation StandardsSatellite Navigation
2 Welcome to the GNSS Satellite Navigation
Standards
The R&S SMBV-K44/-K65/-K66/-K67/-K91/-K92/-K93/-K94/-K95/-K96/-K101/-K102/K103/-K105/-K107/-K110 are firmware applications that add functionality to generate
signals in accordance with GPS, Galileo, GLONASS, QZSS, COMPASS/BeiDou and
SBAS.
The global navigation satellite system (GNSS) solution for the R&S SMBV is suitable
for R&D lab tests or production tests. Supported are all possible scenarios, from simple
setups with individual, static satellites all the way to flexible scenarios generated in real
time. The realtime scenarios can include up to 24 GPS, Glonass, Galileo, QZSS and
BeiDou satellites.
The GNSS key features are:
●
Support of GPS L1/L2 (C/A and P code), Glonass L1/L2, Galileo E1, BeiDou and
QZSS L1, including hybrid constellations
●
Realtime simulation of realistic constellations with up to 24 satellites and unlimited
simulation time
●
Flexible scenario generation including moving scenarios, dynamic power control
and atmospheric modeling
●
Configuration of realistic user environments, including obscuration and multipath,
antenna characteristics and vehicle attitude
●
Static mode for basic receiver testing using signals with zero, constant or varying
Doppler profiles
●
Enabling / disabling particular signal components individually.
●
Support of assisted GNSS (A-GNSS) test scenarios, including generation of assistance data for GPS, Glonass, Galileo and BeiDou
●
Realtime external trajectory feed for hardware in the loop (HIL) applications
●
High signal dynamics1), simulation of spinning vehicles and precision code (P code)
simulations to support aerospace and defense applications
●
Enhanced simulation capabilities for aerospace applications by supporting groundbased augmentation system (GBAS)
See the description "Avionics Standards Digital Standards" for R&S®SMBV operating manual.
1)
Can be subject to export restrictions.
This operating manual contains a description of the functionality that the application
provides, including remote control operation.
All functions not discussed in this manual are the same as in the base software and
are described in the R&S SMBV operating manual. The latest version is available at:
www.rohde-schwarz.com/manual/SMBV100A
14Operating Manual 1173.1427.12 ─ 14
Welcome to the GNSS Satellite Navigation StandardsSatellite Navigation
2.1 Accessing the GNSS Dialog
To open the dialog with GNSS settings
► In the block diagram of the R&S SMBV, select "Baseband > Satellite Navigation".
A dialog box opens that displays the provided general settings.
The signal generation is not started immediately. To start signal generation with the
default settings, select "State > On".
2.2 Scope
Tasks (in manual or remote operation) that are also performed in the base unit in the
same way are not described here.
In particular, it includes:
●
Managing settings and data lists, like storing and loading settings, creating and
accessing data lists, or accessing files in a particular directory.
●
Information on regular trigger, marker and clock signals and filter settings, if appropriate.
●
General instrument configuration, such as configuring networks and remote operation
●
Using the common status registers
Scope
For a description of such tasks, see the R&S SMBV operating manual.
15Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
3 About the GNSS Options
Global navigation satellite system (GNSS) employs the radio signals of several navigation standards, like GPS, Galileo, GLONASS, and BeiDou. For several years, GPS
used to be the only standard available for civilian navigation through its C/A civilian
code. Nowadays, the GNSS signals and systems are undergoing fast development,
some systems are getting modernized and some are new. In the foreseeable future,
several more GNSS satellites utilizing more signals and new frequencies are available.
The GNSS implementation in the R&S SMBV enables you to generate the signal of up
to 6, 12 or 24 GNSS satellites, depending on the installed options. Signal generation is
done in real time and thus it is not limited to a certain time period.
Brief introduction to the global navigation satellite systems (GNSS)
●
GPS
The Global Positioning System (GPS) consists of several satellites circling the
earth in low orbits. The satellites transmit permanently information that can be used
by the receivers to calculate their current position (ephemeris) and about the orbits
of all satellites (almanac). The 3D position of a receiver on the earth can be determined by carrying out delay measurements of at least four signals emitted by different satellites.
Being transmitted on a single carrier frequency, the signals of the individual satellites can be distinguished by correlation (gold) codes. These ranging codes are
used as spreading code for the navigation message which is transmitted at a rate
of 50 bauds.
●
Galileo
Galileo is the European global navigation satellite system that provides global positioning service under civilian control. It is planed to be inter-operable with GPS and
GLONASS and other global satellite navigation systems.
The fully deployed Galileo system consists of 30 satellites (27 operational and 3
spares). Three independent CDMA signals, named E5, E6 and E1, are permanently transmitted by all Galileo satellites. The E5 signal is further subdivided into
two signals denoted E5a and E5b (see Figure 3-1).
●
GLONASS
Glonass is the Russian global navigation satellite system that uses 24 modernized
Glonass satellites touring the globe. Together with GPS, up to 54 GNSS satellites
are provided, which improves the availability and therefore the navigation performance in high urban areas.
16Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Figure 3-1: GNSS frequency bands
●
COMPASS/BeiDou
The fully deployed BeiDou navigation satellite system (BDS) is a Chinese satellite
navigation system. This navigation system is also referred as BeiDou-2 and is
expected in 2020. The BDS is a global satellite navigation system a constellation of
35 satellites to cover the globe. This constellation includes 5 geostationary orbit
satellites (GEO) and 30 non-geostationary satellites; 27 in medium earth orbit
(MEO) and 3 in inclined geosynchronous orbit (IGSO).
The BDS uses frequency allocated in the E1, E2, E5B, and E6 bands.
●
Quasi-Zenith satellite system (QZSS)
The Quasi-Zenith satellite system is a regional space-based positioning system.
The system is expected to be deployed in 2013 and the satellites would be a visible Japan.
In its final deployment stage, the QZSS uses a total number of three regional not
geostationary and highly inclined satellites. The QZSS does not aim to cover the
globe but to increase the availability of GPS in Japan, especially in the larger
towns.
The QZSS uses signals that are similar to the GPS public signals.
●
Assisted GNSS (A-GNSS)
Assisted GNSS (A-GNSS) was introduced to different mobile communication
standards to reduce the time to first fix (TTFF) of a user equipment (UE) containing
a GNSS receiver. This is achieved by transmitting information (assistance data)
mainly about the satellites directly from a base station to the UE.
For example, a standalone GPS receiver needs about 30 to 60 seconds for a first
fix and up to 12.5 minutes to get all information (almanac).
In A-GNSS "UE-based mode", the base station assists the UE by providing the
complete navigation message along with a list of visible satellites and ephemeris
data. In addition to this information, the UE gets the location and the current time at
the base station. That speeds up both acquisition and navigation processes of the
GPS receiver and reduces TTFF to a few seconds.
In A-GNSS "UE assisted mode", the base station is even responsible for the calculation of the UE's exact location. The base station takes over the navigation based
on the raw measurements provided by the UE. Since the acquisition assistance
17Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Overview of the Basic Real-Time GNSS Options
data provided by the base station already serves speeding up the acquisition process, the UE only has to track the code and carrier phase.
Brief introduction to the satellite-based augmentation systems (SBAS)
The satellite-based augmentation system uses geostationary satellites (GEO) to broadcast GNSS coarse integrity and wide area correction data (error estimations), as well
as ranging signal to augment the GNSS.
The SBAS broadcasts augmentation data in the GPS frequency band L1 (carrier frequency of 1575.42 MHz), uses the BPSK modulation, and the C/A PRN code of GPS.
The SBAS provides data for a maximum of 51 satellites. In the SBAS, the term pseudo
random number (PRN) is used instead of the term space vehicle (SV). There are 90
PRN numbers reserved for SBAS, where the numbering starts at 120.
Several SBAS systems are still in their development phase, like for example the SDCM
in Russia Federation, and GAGAN in India.
SBAS systems that are currently in operation argument the US GPS satellite navigation system, so that they are suitable for example for civil aviation navigation safety
needs. The following SBAS systems are supported by R&S SMBV:
●
EGNOS
EGNOS (European geostationary navigation overlay service) EGNOS is the European SBAS system
●
WAAS
WAAS (wide area augmentation system) is the SBAS system in United States
●
MSAS
MSAS (multi-functional satellite augmentation system ) is the SBAS system working in Japan. It uses the multi-functional transport satellites (MTSAT) and supports
differential GPS.
●
GAGAN
GAGAN (GPS aided geo augmented navigation system) is the SBAS implementation by the Indian government.
See also Chapter 3.9.2, "SBAS Configuration", on page 45.
3.1 Overview of the Basic Real-Time GNSS Options
This section gives an overview of the options:
●
GPS (R&S SMBV-K44)
●
Galileo (R&S SMBV-K66)
●
GLONASS (R&S SMBV-K94)
●
QZSS (R&S SMBV-K105)
●
BeiDou (R&S SMBV-K107)
Throughout this description, these options are denoted as basic GNSS options.
18Operating Manual 1173.1427.12 ─ 14
3.1.1 Real-time Generation
●
With the option R&S SMBV-K44, up to six GPS satellites transmitting L1 or L2 signals with C/A-code can be simulated.
●
With the option R&S SMBV-K66, up to six Galileo satellites transmitting E1 signal
can be simulated.
●
With the option R&S SMBV-K94, up to six GLONASS satellites transmitting L1 or
L2 signal can be simulated.
●
With the option R&S SMBV-K107, up to six BeiDou satellites transmitting L1 or L2
signal can be simulated.
The simulation of the QZSS satellite requires the option R&S SMBV-K105 additionally
to any of the options listed above.
3.1.2 Multi-satellite GNSS Signal
The instrument calculates a multi-satellite GNSS signal in three different simulation
modes, the static mode, the auto localization mode and the user localization mode.
About the GNSS OptionsSatellite Navigation
Overview of the Basic Real-Time GNSS Options
In "Static mode", static satellites with constant Doppler shifts are provided for simple
receiver test, like receiver sensitivity, acquisition and tracking test, or production tests.
The selection and configuration of any localization data, such as receiver location for
instance are not enabled.
See Chapter 5.1, "Generating a GNSS Signal for Simple Receiver Tests (Static
Mode)", on page 213.
The superposition signal of up to six dynamic satellites at a specific receiver location is
generated in one of the localization modes. The major difference to the static mode
implies the possibility to specify the receiver's location. Although, both the localization
modes are provided for the generation of a realistic GNSS signal, there are some differences between them.
●
"Auto Localization"
This mode is provided for the generation of a GNSS signal with automatic
exchange of satellites. The automatic exchange of satellites improves the position
dilution of precision and ensures satellite visibility at the simulated receiver location.
This mode ensures an optimal satellite constellation, automatic dynamic calculation
of the satellite power at any moment and ephemeris projection from the selected
almanac.
In this simulation mode, the connected GNSS receiver can be forced to obtain a
3D fix at a predefined or user-defined static geographical location. Instrument
equipped with the option GNSS enhanced R&S SMBV-K92 can also simulate moving receivers (see Chapter 3.5.1, "Moving Scenarios", on page 28).
●
"User Localization"
This mode provides flexible configuration of the satellite constellation, the power
settings and the individual satellites parameters. For instruments equipped with
assistance option R&S SMBV-K65, this mode also enables the extraction of the
navigation message from RINEX files. Dynamic exchange of satellites is possible
with activation and deactivation of the individual satellites. The power settings are
19Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Overview of the Basic Real-Time GNSS Options
enabled for configuration but the automatic dynamic calculation function of the
instrument can also be utilized.
This mode is required for the generation of user-defined assisted GPS test scenarios.
The Table 3-1 gives an overview of the supported functionality per simulation mode.
Some functionalities require further options.
Table 3-1: Cross-reference between the simulation mode, supported functionality and the required options
Simulation mode /
Function
Configuration of static receiver location No Yes Yes R&S SMBV-K44/K66/K94/
GNSS system configuration Yes Yes Yes R&S SMBV-K44 and
Almanac/RINEX Almanac Almanac Almanac and
Projection of navigation message No Yes Yes R&S SMBV-K44/K66/K94/
S.P.O.T. display No Yes Yes R&S SMBV-K44/K66/K94/
Assistance GNSS data generation No No Yes R&S SMBV-K44/K66/K94/
Configuration of satellite constellation Yes No Yes R&S SMBV-K44/K66/K94/
Static Auto localization User localization Required options
K105/K107
R&S SMBV-K66 and
R&S SMBV-K94 and
R&S SMBV-K105 and
R&S SMBV-K107
R&S SMBV-K44/K66/K94/
RINEX file supported
K105/K107
R&S SMBV-K65/K67/K95/
K105/K107 for RINEX files
K105/K107
K105/K107
K105/K107 and
R&S SMBV-K65/K67/K95
K105/K107
Power mode User Auto Auto/User R&S SMBV-K44/K66/K94/
K105/K107
Exchange of satellites No Automatic Manual R&S SMBV-K44/K66/K94/
K105/K107
Maximum number of satellites Up to 12/24 Up to 12/24 Up to 12/24 R&S SMBV-K91/-K96
Motion files
Motion smoothening
Extract attitude from motion file
Time conversion configuration Yes No Yes R&S SMBV-K92
Navigation message configuration Configurable Read-only Configurable R&S SMBV-K92
Atmospheric configuration Yes Yes Yes R&S SMBV-K92
Static multipath configuration No No Yes R&S SMBV-K92
Automatic Multipath&Osculation scenarios
No Yes Yes R&S SMBV-K92
No Yes Yes R&S SMBV-K92 and
R&S SMBV-K102
20Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Overview of the Basic Real-Time GNSS Options
Simulation mode /
Function
Antenna Pattern/Body mask No Yes Yes R&S SMBV-K102
Attitude/Body rotation angle files
User-defined vehicle spinning
Hardware in the loop (HIL) No Yes Yes R&S SMBV-K92 (motion
File conversion tool
SBAS configuration
Modulation control
Signal dynamics
Static Auto localization User localization Required options
No Yes Yes R&S SMBV-K92 and
R&S SMBV-K103
only)
R&S SMBV-K103 (motion
and attitude)
No - Yes R&S SMBV-K44 and
R&S SMBV-K110
Yes No No R&S SMBV-K44/K66/K94/
K105/K107
3.1.3 GNSS System Configurations
Instrument equipped with the GNSS basic options GPS, Galileo, GLONASS, BeiDou
and QZSS can generate the signal of hybrid GNSS satellite constellation with radio signals of all navigation standards. Mixed configurations are enabled only in the common
or close-range frequency bands, e.g. L1/E1.
GNSS system configurations can be also used to configure general-purpose global
parameters for the simulation.
3.1.4 Signal Dynamics
For basic receiver testing, the R&S SMBV generates signals with varying Doppler
effects in static mode. Thus you can define Doppler profiles with configurable maximum dynamics (velocity, acceleration and jerk).
3.1.5 Modulation Control
In static mode, the instrument allows you to disable modulation components individually, like data source, spreading code, time sequence, meandering, navigation message.
3.1.6 Multiple Almanacs
The instrument supports the configuration of the almanac files used. One almanac file
per GNSS navigation standard can be selected.
The Galileo and Beidou satellite constellation are not yet fully in orbit. Hence, no almanac files for Galileo and BeiDou are available. In this implementation, predicted Galileo
21Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Overview of the Basic Real-Time GNSS Options
and Beidou almanac files are provided for test purposes. The almanac files for GPS
and Galileo use the same format.
Current GNSS almanac data can be downloaded via the Internet and stored on the
hard disk of the instrument:
●
US Coast Guard Navigation Center GPS Homepage http://www.navcen.uscg.gov/?
pageName=gpsAlmanacs
The almanac files are named xxx.alm (for YUMA files) or xxx.al3 (for SEM
files),
Where xxx denotes the day of a year
●
http://www.celestrak.com/GPS/almanac/
The naming convention of the almanac file is: almanac.sem/
yuma.weekXXXX.YYYYYY.txt,
Where xxxx denotes the GPS week and yyyyyy the time of almanac (TOA)
●
ftp://ftp.glonass-iac.ru/MCC/ALMANAC/
The file extension of the Glonass almanac file is: xxx.agl
●
Japanese Space Agency homepage http://qz-vision.jaxa.jp/USE/en/almanac
Available are QZSS almanacs or QZSS+GPS almanac data files.
The almanac files are named zzyyyyxxx.alm (for YUMA files) or
zzyyyyxxx.alm.xml (for XML files),
Where zz=q for QZSS almanacs and zz=qg for QZSS+GPS almanacs;
yyyy denotes the year and xxx denotes the day of a year.
For detailed information on the content and frame structure of navigation data, refer to
the specifications.
3.1.7 On-the-fly Configuration of the Satellites Constellation
The simulation mode "User Localization" makes the satellite constellation user-definable. The individual satellite parameters and the navigation message parameters are
enabled for configuration. Additionally, active satellites can be turned off or the satellite
constellation can be extended with new satellites at any time and on-the-fly. Changes
in the satellite constellation do not cause an interruption of the currently running signal
calculation. Changes in ephemeris of an active satellite and the power settings are performed without signal calculation restart, too. Hence, satellites ephemeris adjustment
can be performed during the time the satellite is disabled and the updated parameters
are used from the moment this satellite is active again. This functionality can be used
to perform manual exchange of satellite's at user-defined moment of time.
This on-the-fly reconfiguration during signal generation is especially beneficial by time
consuming measurements or test.
3.1.8 Signal Generation with Projection of the Ephemeris Navigation Data
In GPS and GLONASS, there is a requirement regarding the time span between the
simulation time and the reference time of the current satellite ephemeris page. This
22Operating Manual 1173.1427.12 ─ 14
Overview of the Basic Real-Time GNSS Options
time span has to be within the maximum allowed value of two hours (GPS) and of half
an hour (GLONASS).
To overcome this limitation in the simulation time, the instrument applies a special algorithm for projecting the ephemeris navigation data. This projection algorithm updates
the ephemerides and allows the generation of a navigation message without limitation
in the simulation time.
3.1.9 Dynamic Exchange of Satellites
In this implementation, the exchange of satellites can be performed automatically or
manually.
●
To enable the instrument to perform automatic exchange of satellites, select the
"Auto Localization" mode.
In this mode, the instrument constantly monitors and updates the simulated satellite's constellation based on two criteria, the optimal satellite constellation with minimum PDOP and the satellite's visibility respecting the Elev. Mask Angle. The
PDOP is a constellation parameter that is calculated by the instrument and displayed in real time. The satellite's visibility is a satellite parameter which indicates
that the satellite elevation at a specific user location is above a configurable elevation mask.
For the particular satellite's conditions and the number of satellites, the software
calculates and monitors the PDOP and the satellite's visibility values. It selects the
moment of time to change the satellite's constellation. Satellites that do not fulfill
the criteria for minimum PDOP and sufficient visibility are exchanged dynamically
and on-the-fly. Information about the expected time of the next upcoming
exchange is provided by the parameter Next Constellation Change.
See Chapter 5.2, "Generating a GNSS Signal with Automatic Exchange of the Sat-
ellites", on page 213.
●
In "User Localization" mode, the exchange of the satellites is not performed automatically, but the satellite's constellation is fully configurable. Satellites can be
turned off, reconfigured and turned on again, the existing satellite constellation can
be extended with new satellites. Hence, an exchange of the satellites can be configured and performed manually at any moment of time.
See Chapter 5.3, "Generating a GNSS Signal with Manual Exchange of the Satel-
lites", on page 214.
About the GNSS OptionsSatellite Navigation
3.1.10 Flexible Power Configuration and Automatic Dynamic Power Control
The instrument employs a dynamic power control concept. To provide better flexibility,
two power modes are provided, the "Auto" and the "User" power modes.
●
"User" power mode is intended for dynamical configuration of the power of each
satellite separately and manually.
●
"Auto" power mode enables an internal dynamical automatic power control. The
power is calculated automatically based on the satellite-to-receiver distance which
varies with the time.
23Operating Manual 1173.1427.12 ─ 14
Overview of the Basic Real-Time GNSS Options
For examples and information about the power calculation, see:
●
Chapter 4.10.1, "Power Configuration", on page 125
●
Chapter 5.12, "Adjusting the Power Settings", on page 224.
3.1.11 Simulation of Uninterrupted Location Fix
The simulation of uninterrupted location fix requires a GNSS signal that fulfills the following conditions:
●
An optimal satellite's constellation is selected and monitored constantly, i.e. the
exchange of the satellites is performed automatically.
●
The power of the satellites is monitored and updated constantly depending on the
satellite-to-receiver distance and some channel parameters, e.g. atmospheric
effects.
●
The age of the ephemeris (t - toe) is respected.
For example, the simulation time is always within the allowed time span of 2h
around the GPS reference time of the current ephemeris page. For GLONASS, this
time is usually 30 minutes.
About the GNSS OptionsSatellite Navigation
The Table 3-2 gives an overview on how the localization modes fulfill these criteria.
Table 3-2: Criteria for the generation of GNSS signal for simulation of uninterrupted location fix
Criteria
Simulation
Mode
"Auto Localization"
"User Localization"
Optimal Satellite's Constellation
Selected and updated automatically
Automatic dynamic exchange
of the satellites
Initial optimal satellite's constellation
Manual user-defined exchange
of the satellites
Power Monitoring and
Update
Performed automatically Projection of the ephem-
Performed automatically Projection of the ephem-
Age of Ephemeris
eris from the almanac
eris or many ephemeris
pages are made available
Both localization modes provide a realistic signal. The decision which localization
mode is used is a trade-off between the following:
●
The better accuracy of the ephemeris retrieved from a RINEX file or a manual
ephemeris configuration
●
The automatic selection of the optimal satellite's constellation with automatic
exchange of the satellites.
See:
●
Chapter 5.2, "Generating a GNSS Signal with Automatic Exchange of the Satellites", on page 213
●
Chapter 5.3, "Generating a GNSS Signal with Manual Exchange of the Satellites",
on page 214
24Operating Manual 1173.1427.12 ─ 14
Enhancements of Assisted GNSS Options GPS, Galileo and GLONASS
3.1.12 Real-Time S.P.O.T. Display
The real-word situation of disappearance and reappearance of satellites can be
observed in real time in the special "Real-Time S.P.O.T." (Satellites and Position Online
Tracker) display. The "Real-Time S.P.O.T." view is also a dynamic display of several
parameters like HDOP, PDOP, receiver's location, elapsed time and the trajectory of a
moving receiver.
The display is enabled for "Auto Localization" and "User Localization" modes.
3.2 GPS P-Code (R&S SMBV-K93)
The option GPS P-Code (R&S SMBV-K93) is available for instruments equipped with
option GPS (R&S SMBV-K44).
It enhances the option GPS with the following functionality:
●
Generation of a position accuracy (P-Code) signal
●
Configuration of P or C/A+P satellite signals, additionally to the civilian C/A signal.
About the GNSS OptionsSatellite Navigation
About the P-Code
P-Codes are one week long codes with a high chip rate 10.23 MHz. The higher chip
rate significantly increases the performance compared to the civilian C/A codes used
by commercial receivers. P-Code signal provides better carrier to noise sensitivity.
Another difference compared to the C/A signals is that P-Code signals are only sensible to less than 30 m multipath delay whereas C/A signals are sensible to 300 m.
See Chapter 5.10, "Generating a GPS Signal Modulated with P Code", on page 222.
3.3 Enhancements of Assisted GNSS Options GPS, Galileo and GLONASS
This section gives an overview of the Assisted GNSS Options.
Assisted GNSS option Required basic option Enhancement
Assisted GPS
(R&S SMBV-K65)
Assisted Galileo
(R&S SMBV-K67)
GPS
(R&S SMBV-K44)
Galileo
(R&S SMBV-K66)
Functionality for A-GPS/A-GNSS test scenarios for
3GPP FDD, GSM and EUTRA/LTE
Generation of user-defined test scenarios
Assisted GLONASS
(R&S SMBV-K95)
GLONASS
(R&S SMBV-K94)
Functionality for A-GLONASS/A-GNSS test scenarios for 3GPP FDD and EUTRA/LTE
25Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Enhancements of Assisted GNSS Options GPS, Galileo and GLONASS
3.3.1 Support of RINEX Files
Additionally to the almanac files, a Receiver Independent Exchange Format RINEX
files are supported. RINEX files are standard formats generated by Control Stations
(CS) and many commercial receivers. RINEX Navigation Files usually comprise the
ephemeris sets for several satellites with different TOE and TOC. One RINEX File is
enough to describe satellite orbits for a period longer than two hours and sometimes
up to one day.
You can download RINEX files for the Internet and store them on the hard disk of the
instrument, e.g. :
●
http://cddis.gsfc.nasa.gov/gnss_datasum.html#brdc
●
ftp://ftp.glonass-iac.ru/MCC/BRDC
●
http://qz-vision.jaxa.jp/USE/en/ephemeris
3.3.2 Predefined Test Scenarios as Basis for A-GNSS Protocol and Conformance Testing
An instrument equipped with the assisted options supports test scenarios as basis for
A-GPS/A-GLONASS/A-GNSS protocol and conformance test cases. A-BeiDou/A-Galileo test scenarios are included in the corresponding basic options. Some of the test
cases require additional options.
Test scenario vs. test case
An instrument equipped with the required options provides predefined test scenarios,
not the standard conform test cases.
The provided test scenarios are suitable basis for the test cases. However, to perform
a particular test case as specified by the 3GPP test specification, configure the settings
as required. In particular, adjust the receiver location, the simulation time, active satellites in the pre-selected satellite constellation, power setting, etc.
Refer to the corresponding 3GPP test specification for the required values.
See also Chapter 5.7, "Generating an A-GNSS Test Signal", on page 217.
For an overview of the supported test scenarios, see Chapter G, "List of Predefined
Test Scenarios", on page 465.
3.3.3 Custom Build Scenarios
The assisted options (R&S SMBV-K65/-K67/-K95) and are not limited to be used for AGNSS testing exclusively. Despite the predefined scenarios, it is also possible to define
any user-specific test scenario.
For testing of standalone GNSS receivers, the assisted options offer full flexibility on
the simulated satellites including definition of the complete navigation message. The
simulation mode "User Localization" can be used to get an optimal satellite's constellation and to adjust the navigation message to the exact requirements.
26Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Extension to 12 / 24 Satellites (R&S
The basic BeiDou option (R&S SMBV-K107) is sufficient for this kind of tests. Additional assisted option is not required.
See Chapter 5.5, "Generating A-GPS Custom Build Scenarios", on page 215.
3.3.4 Generation of Assistance Data
Besides generating the satellite signals for predefined test scenario, the assisted
options (R&S SMBV-K65/-K67/-K95) also provide assistance data in line with the simulated scenario. Assistance data can be provided to the UE by a protocol tester. Certainly, this also applies to user-defined test scenarios.
For the generation of A-QZSS and A-BeiDou user-defined test signals, the basic
QZSS/BeiDou option (R&S SMBV-K105/-K107) is sufficient. Additional assisted option
is not required.
See:
●
Figure 5-2
●
Chapter 5.8, "Generating a GNSS Assistance Data", on page 217
SMBV-K91/-K96)
3.4 Extension to 12 / 24 Satellites (R&S SMBV-K91/-K96)
These options extend the maximum number of simulated satellites.
●
Instrument equipped with the option R&S SMBV-K91 is enabled to generate the
signal of up to 12 configurable satellites.
Any hybrid 12-satellite configuration is possible, for example a combination like 10
C/A GPS + 1 Galileo E1 + 1 GLONASS R-C/A. The available satellites depend on
the availability of the basic options, on the enabled standards in the "GNSS System
Configurations", and the selected "RF Band"
●
The R&S SMBV-K96 requires the option R&S SMBV-K91 and further extends the
maximum number of simulated satellites.
Instruments equipped with this combination can generate the signal of up to 24
GPS C/A, Galileo E1, Glonass R-C/A and BeiDou B1-C/A satellites.
The option R&S SMBV-K96 does not enhance the number of P-code satellites/
taps.
See Chapter 5.21, "Generating GNSS Signal with Several Instruments", on page 254.
There is a limitation of the maximum number of simulated satellites, depending on
whether P code signal and BeiDou satellites are enabled in the GNSS system configuration or not. For details, see Chapter E, "Channel Budget", on page 461.
27Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Functional Overview of Option GNSS Enhanced (R&S
SMBV-K92)
3.5 Functional Overview of Option GNSS Enhanced
(R&S SMBV-K92)
This option enhances the basic options R&S SMBV-K44/-K66/-K94/-K105/-K107 with
the following functionality:
●
Support of motion files
●
Smoothening of the used defined trajectories
●
Real-time motion vectors or hardware in the loop (HIL)
●
Modeling static multipath profiles
●
Configuration of atmospheric effects
●
System time conversion
●
Leap second simulation parameters.
For detailed description, see:
● Moving Scenarios....................................................................................................28
● Static Multipath Signal Generation..........................................................................29
● Configuration of the Atmospheric Parameters........................................................ 29
● Time Conversion Configuration...............................................................................30
● Leap Second Simulation......................................................................................... 30
● Internal Waypoint Resampling................................................................................ 30
● Motion Smoothening Using Vehicle Description File...............................................30
● Hardware in the Loop (HIL).....................................................................................31
3.5.1 Moving Scenarios
The option GNSS enhanced (R&S SMBV-K92) enhances the basic GNSS options by
user-definable moving scenarios.
The following test scenarios require moving scenario:
●
A-GPS test scenarios for 3GPP FDD and GSM (Performance Test Scenario#3)
●
CDMA test case "3GPP2 Moving Test Scenario"
●
A-GNSS Scenario 5 for EUTRA/LTE
Another application field of the moving scenarios is the testing of standalone GNSS
receivers.
In the R&S SMBV, a movement, i.e. a moving receiver is defined in one of the following
ways:
●
By a waypoint file that simulates a "moving" of the connected GNSS receiver
A waypoint can be defined with:
– The WGS 84 geodetic coordinates, see Chapter A.1.1, "Waypoint File Format",
on page 435
– The East-North-Upper (ENU) 2D vector trajectory parameters (line, arc), see
Chapter A.1.2, "Vector Trajectory File Format", on page 436
●
By extracting of the location data from the NMEA files, see Chapter C, "NMEA Sce-
narios", on page 453
28Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Functional Overview of Option GNSS Enhanced (R&S
●
By configurable locations in Cartesian or geodetic coordinates with potentially
defined velocity vector or velocity magnitude parameters in the *.xtd file, see
Chapter A.1.4, "Trajectory Description Files", on page 439
●
By the provided predefined waypoint files for the land, ship, aircraft and spacecraft
vehicles
●
By the KML file format of third-party software, like the Google Earth or Google
Maps. For description of the file format, refer to the Google Earth documentation.
Moving vs. motion
All these file formats describe a moving receiver and are suitable for the simulation of a
movement from one waypoint to the next.
However, only the more extensive file format *.xtd is suitable to describe a motion
including high dynamics e.g. velocity and attitude. In instruments equipped with the
R&S SMBV-K103 option, this file format simulates additionally a body rotation and attitude profile of the receiver’s vehicle.
See also Chapter 3.8, "GNSS Extension for Spinning and Attitude Simulation
(R&S SMBV-K103)", on page 43.
SMBV-K92)
For further information, see Application Note 1GP86 "GPS, Glonass, Galileo, BeiDou
Receiver Testing Using a GNSS Signal Simulator".
3.5.2 Static Multipath Signal Generation
The instrument provides the possibility to simulate the GNSS signal of one or more satellites that undergoes static multipath propagation effects. The static multipath propagation is implemented as a tapped delay model.
See:
●
Chapter 5.9, "Creating Multipath Scenarios", on page 218
●
Chapter 4.4.6, "Land Mobile Multipath", on page 84.
3.5.3 Configuration of the Atmospheric Parameters
In instruments equipped with the option GNSS enhanced (R&S SMBV-K92), the ionospheric navigation parameters and both ionospheric and tropospheric models of the
installed GNSS standards are enabled for configuration.
A possible application of the activation and deactivation of the ionospheric and tropospheric models is to simulate the variation in the pseudorange of the corresponding
GNSS satellites. The ionospheric navigation parameters define what the satellites are
transmitting as ionospheric correction parameters. The models configuration describes
the actual ionospheric and tropospheric models used in the satellite-receiver channel
simulation.
29Operating Manual 1173.1427.12 ─ 14
About the GNSS OptionsSatellite Navigation
Functional Overview of Option GNSS Enhanced (R&S
3.5.4 Time Conversion Configuration
The instrument supports an advanced function for transformation of the GNSS time to
the universal time coordinate basis (UTC) and vice versa. The provided GNSS system
time conversion parameters are zero-order and first order system clock drift parameters in addition to the current leap second (see Chapter 3.5.5, "Leap Second Simula-
tion", on page 30). The leap second describes the difference between the GPS, Gali-
leo, GLONASS or BeiDou system time and UTC system time. It is for example possible
to simulate a system time drift between GPS and Galileo by configuring different time
conversion sets for both UTC-GPS and UTC-Galileo conversion parameters.
The time conversion parameters can be either manually configured or fetched from the
RINEX header. It is recommenced to use the default configurations without system
time offset and/or drift.
3.5.5 Leap Second Simulation
The instrument enables the simulation of leap second in a straightforward way. The
simulation requires only the date and sign of the next leap second, further calculations
are performed automatically.
SMBV-K92)
3.5.6 Internal Waypoint Resampling
For the simulation of motion and body rotation, the R&S SMBV uses a 100 Hz internal
clock. The motion files you load into the instrument can contain waypoints or a combination of waypoints and attitude coordinates with a varying resolution or resolution different than the internally used. The R&S SMBV interpolates (resamples) the motion
files and transforms the used resolution to the internal resolution of 10 ms.
The internal resampling algorithm is based on the great circle approximation. The
instrument resamples the vehicle attitude (yaw/heading, pitch/elevation, roll/bank)
parameters linearly in a common reference basis. Depending on the content of the
motion file, in particular on the way the velocity is defined, the resampling is performed
accordingly.
For more information, see:
●
Chapter A.1.5, "Resampling Principle", on page 443
●
Chapter A.1.6, "Calculating the Maximum Time Duration of a Movement File",
on page 444.
3.5.7 Motion Smoothening Using Vehicle Description File
The selected motion file (for example the waypoint file) contains a set of random waypoints, often without knowledge about the realistic dynamic. Smoothening is a function
that regenerates the motion file based on user-defined maximum dynamics (speed,
acceleration and jerk), sampling rate and proximity (deviation error). The maximum
dynamics and the proximity are retrieved form the vehicle description file *.xvd.
30Operating Manual 1173.1427.12 ─ 14
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