Record and Playback Systems in Multi-GNSS Receiver Testing
Record and playback systems (RPSs) such as the new Spirent GSS6400 can be used at many stages of the GNSS receiver design cycle and for many different tasks. However, one application that may not seem immediately obvious is in testing the ability of multi-GNSS receivers to work with both existing and future satellite systems.
Clearly, the RPS cannot be used to playback signals from non-existent satellites. But used in conjunction with a simulator, the RPS can play a key role in investigations into interoperability.
Under this test setup, the user would capture real-world GPS signals out in the field using the GSS6400 RPS and then return to the laboratory where the signals can be replayed with total fidelity and repeatability. The addition of a multi-GNSS simulator would then allow simultaneous creation of signals from as-yet-unlaunched satellites, say from the Galileo constellation. Then, so long as the replayed and simulated signals are correctly synchronised, then the operator will be able to assess the ability of the receiver under test to work with both the current and future GNSSs.
Alternatively, the same test setup could also be of use to developers of future GNSS constellations in determining exactly which signals will work well with the existing family of GNSSs.
Finally, the GSS6400 RPS can also be used to capture and replay the output from any of Spirent's family of GNSS simulators, offering the advantage that the simulator can be freed up for future projects while the RPS performs those tests that require multiple iterations.
If you would like more information on Spirent’s Record & Playback System, download the eBook or if you’re involved in Multi-GNSS download the Application Note “Multi-GNSS for Technology Developers”