Microprocessor Bit Synchronizer for Shuttle Payload Communications

An example of the growing influence of the microprocessor in communications is illustrated in this description of the payload bit synchronizer and other related payload signal processing functions for the Space Shuttle. Stored in firmware the microprogrammed control at 2.56 M-instructions/s accomplishes bit synchronization, matched filter detection, NRZ-
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conversion and frame synchronization for some thirty combinations of PCM formats and data rates.