Development of Support Equipment for SATCOM Avionics

Abstract

Demand for satellite communication (SATCOM) infrastructure has led to the development of a geosynchronous spacecraft to enable communications between ground and mobile terminals for video data. When fully loaded, the ground support equipment (GSE) provides handling for payload data of 1.2 Gbps distributed across more than 100 continuous carrier terminals or 1000 time division multiple access (TDMA) terminals. This paper assesses the implementation of GSE to verify the hardware design of this multi-radio, multi-terminal avionics unit. The GSE contains a unique design based around a communications slice, each of which provides one of four L-band interfaces to the unit under test (UUT) for both transmit and receive data. The GSE uses a channel emulator to impose impairments on the radio frequency (RF) signals to include noise, propagation delay, and dynamic frequency offset. For adjacent channel loading, the GSE contains an arbitrary waveform generator (A WG) that can implement simulated terminals in a composite waveform. This function complements the slices that contain servers connected to software defined radios (SDRs). The GSE employs an Ethernet backbone for subsystem control and to move the payload data to and from the SDRs and to the A WG. Test software in the test controller implements ETSI Digital Video Broadcast (DVB) standards for the baseband and high layer data. The test software is based around a Ground Support Equipment Operating System (GSEOS) environment, which provides test logging and automation for a traceable, repeatable environmental test campaign. The test software maintains compatibility with an embedded test software (ETS) on the UUT, which provides customized interfaces for moving higher rate data to and from the UUT.