“A powerful flexible choice for R&D applications, supports multi-system, multi constellation GNSS testing”
The GSS8000 Multi-GNSS constellation simulator series has been designed to meet all the demanding requirements of research and development teams involved in satellite navigation and positioning systems.
Due to its modular design, the GSS8000 can be readily adapted to the requirements of different applications. Multiple RF carriers, selected from a range of constellations and signals, can be accommodated in a single signal generator chassis.
A GSS8000 system comprises a controller computer running Spirent’s powerful simulation software SimGEN, and a signal generator configured to meet specific test needs. Multiple chassis can be combined to form an integrated, coherent signal generator if more signals or outputs are required.
An extensive range of system extensions allows users to tailor their system to their specific needs, today and in the future.
Standard capabilities enabled through SimGEN include simulation of atmospheric effects, multipath reflections, terrain obscuration, antenna reception gain and phase patterns, differential corrections, trajectory generation for land, air, sea and space vehicles and comprehensive error generation.
An easy to use graphical user interface (GUI) allows modification of a wide range of variables from pre-set defaults, enabling the user to focus their time on the areas of test important to them. Complete scenarios are readily shared between systems, supporting collaborative activities and speeding up the R&D cycle.
Due to its modular design, the GSS8000 can be readily adapted to the requirements of different applications.

Multiple RF Carriers
- Up to 3 RF carriers, selected from a range of constellations and signals, can be accommodated in a single signal generator chassis
Realtime Simulation
- Standard capabilities enabled through SimGEN include simulation of atmospheric effects, multipath reflections, terrain obscuration, antenna reception gain and phase patterns, differential corrections, trajectory generation for land, air, sea and space vehicles and comprehensive error generation
Intuitive and Easy to Use Interface
- An easy to use graphical user interface (GUI) allows modification of a wide range of variables from pre-set defaults, enabling the user to focus their time on the areas of test important to them. Complete scenarios are readily shared between systems, supporting collaborative activities and speeding the R&D cycle
The GS8000 is packed with user focused features - brought together these make the GS8000 the testing product of choice:


Multiple Signals Combined
- Up to 3 carriers in a single chassis
- GPS, GLONASS, Galileo, BeiDou-2 and SBAS supported
- Architecture supports future Compass & QZ signals
- Open and encrypted signals available
- Up to 48 channels in a chassis plus up to 192 additional programmable multipath channels (total 240 channels per chassis)
- One or two RF outputs per chassis
Comprehensive Modelling
- Extensive multipath modelling
- Antenna gain and phase pattern
- Lever arm effects modelled
- Ionosphere and Troposphere modelling
- DGPS corrections
- Pseudorange ramps for RAIM testing
- ISCN support
Unmatched Pedigree and Support
- Regional support centre network
- E-mail, online and telephone support
- Regular software upgrades
- Knowledge base and on-line tracking system
- Every system includes deep and comprehensive features from over 20 years of GNSS testing
experience
- Application notes and test methodologies
Standard Features Enabled by SimGEN Include
- Simulation of multipath reflections, terrain obscuration, antenna reception gain patterns, differential corrections, trajectory generators for land, air, sea and space vehicles and comprehensive error generation and system modelling.
- Also supplied as standard is a low-latency, high-rate hardware-in-the-loop capability.
Whether testing with multiple signals from a single constellation or testing hybrid systems with signals from multiple constellations, the GSS8000’s modular design can be configured to meet your needs. An enormous range of system configuration options is supported on the GSS8000 system, a few examples are shown below.

- GSS4150 (for LAAS VDB emulation)
- GSS7765 (Modelled interference generator)
- SimINERTIAL (for GPS / inertial system testing)
- SimDATA (data capture and handling package)
- SimREMOTE (remote control and hardware-in-the-loop testing)
- SimAUTO (automotive sensor simulation, coherent with GPS L1, L2 signals)
- SimMCODE / SDS M-Code* (for testing GPS M-Code receiver technology)
*available to authorised users only
| Example Configuration Options |
| GSS8000 |
+ |
SimGEN |
+ |
SimINERTIAL |
| GSS8000 |
+ |
SimGEN |
+ |
GSS4150 |
| GSS8000 |
+ |
SimGEN |
+ |
Users systems |
Extensions and Options
Increasingly, GNSS receivers and sensors do not operate in isolation. If development and verification testing of integrated systems is required then it is essential that other sensors are emulated and other signals are reproduced coherent with the GNSS signals.
The GSS8000 has been designed to operate with all of Spirent's extensive range of options and system extensions. For example: Inertial sensors can be emulated by SimINERTIAL. Wheel tick sensors and VSS signals are reproduced by SimAUTO. Noise and channel interference can be reproduced by the GSS7765. LAAS VDB broadcasts are produced by the GSS4150. In all cases, coherent control is achieved via Spirent's SimGEN software suite.
SimINERTIAL: Operational performance of an Integrated GPS/Inertial (IGI) system can be established in the laboratory using real-time emulation of the inertial sensor outputs along with a GSS8000 constellation simulator. All signals are coherently generated to exactly match the simulated vehicle trajectory. Typical inertial sensor performance can be represented by a sensor error model driven by the simulated motion, with appropriate coefficients entered by the user.
SimMCODE / SDS M-Code*: The GSS8000 series supports AES M-Code testing with SimMCODE and SDS M-Code testing via the SDS extension to SimMCODE.
*Available to authorised users only
SimCLASS / SimSAAS*: Provides SA/A-S simulation for testing of SAASM equipment using customer furnished AOCs.
*Available to authorised users only
SimAUTO: SimAUTO provides a turnkey solution to testing integrated vehicle navigation systems comprising GPS and dead reckoning (DR) sensors such as gyros or wheel ticks. SimAUTO allows parameters such as vehicle geometry and odometer pulse rate to be set and saved to a vehicle
personality file for future use.
Advanced interference simulation GSS7765: The GSS7765 offers a very broad range of interfering signal options, which may be used to represent a varied array of threat sources. The GSS7765 also supports noise generation with variable bandwidth and can be configured to support up to 4 fully independent interference sources.
Hardware-in-the-loop extensions SimREMOTE: Extends the GSS8000's comprehensive standard remote control facility to include GPIB and SCRAMNet+ in addition to Ethernet.
GSS4150*: The GSS4150 VDB simulator has been designed to provide an integrated source of the VHF data broadcast element of GBAS, such as LAAS. The data messages are constructed in real time using error modelling applied to a simulated GPS reference receiver and fixed data entered by the user. The GSS4150 varies the signal level in response to the distance of separation from the defined simulated transmitter location and the simulated aircraft position, and in response to the simulated VHF antenna reception pattern.
*For more details on the Spirent GSS4150, please contact your local Spirent representative