Microprocessor bit synchronizer for Shuttle payload communications

Communication with Shuttle-launched payloads will be accomplished initially over a limited range up to ten nautical miles via the Space Shuttle Orbiter payload communications subsystem. Command data are transmitted to, and telemetry data are received from payloads on multiple S-band frequency channels. A description is presented of aspects of NASA Payload Signal Processor (PSP) development, giving particular attention to the innovative features of the microprogrammable bit synchronizer/detector. The PSP performs the basic functions of subcarrier demodulation, bit and frame synchronization as well as matched filter bit detection. The PSP microprocessor performs the complete 32 bit multiple precision correlation in 19 instruction cycles.