TIME-DIVISION MULTIPLEX WITH SYNCHRONIZATION SYSTEM.

This report describes a digital multiplex system, and more particularly a pulse code modulation, time-division multiplex system having improved bit and frame synchronization circuits in the demultiplexer. The digital multiplex system was developed for the Reliable Acoustic Path program test vehicles. This time-division multiplex system accomplishes a multichannel transmission capability by digitally coding a number of clipped input signals at distinct time intervals. The samples from individual data channels are then transmitted sequentially so that only one circuit from data source to receiver is completed at any given instant. Bit and Frame synchronization in the demultiplexer are accomplished by observing certain properties of the multiplexed data stream and by perturbing the demultiplexer timing countdown. The implementation and operation of the time-division multiplex is described and pertinent illustrations are included. Author