STRS GPS and Galileo Receiver for the ISS (GARISS)(LEW-20096-1)

The GARISS waveform implements a GNSS receiver that performs position determination using the L5/E5a band of the GPS/Galileo satellite constellations. It was operated in a space environment on the SCaN Testbed platform aboard the ISS. The waveform takes L-band input as one bit samples at 38 MHz and uses FPGA and CPU processing to implement acquisition, tracking, navigation message decoding, and position-velocity-time (PVT) generation. Signals from both constellations are combined when generating PVT, which often leads to better visibility than using a single constellation alone. The computed PVT and other receiver metrics are output as telemetry logs.