Wideband Digital Signal Processor
The Quasar Satellite Technologies Channel Combiner performs spectral synthesis for the multi-beam phased-array receiver.
The Quasar Channel Combiner signal receives up to 80 MHz of bandwidth divided into 10 dual-polarisation beams, each with a bandwidth of 8 MHz, channelized and oversampled at ~17.6 kHz, and quantised with 16 bits per sample. The signal processor will implement four modes of operation.
The Channel Combiner executes on a single server equipped with an NVIDIA Connect-X 5 dual-port Network Interface Card (NIC). A 100GbE port receives a stream of CODIF (CSIRO Oversampled Data Interchange Format) UDP packets from the phased-array beam-former, and a 10GbE port sends a stream of VITA-49 UDP packets for downstream signal processing.
The Channel Combiner acts as a synthesis filter bank, combining fine channels into wider bands of tunable width and center frequency, while applying windows in both the time and frequency domains to improve signal quality.