Data-transmission system using binary split-phase code

Abstract

For the transmission of binary signals in a succession of pulse cycles, a message pulse generated at a transmitting station during the first half of a cycle is inverted in the second half thereof before being sent over a line to a remote receiving station. There a synchronization signal is extracted from the incoming pulse train to produce a series of equispaced timing pulses normally occurring in the middle of the second half of each cycle. This incoming pulse train is subtractively combined with a replica thereof, relatively phase-shifted by half a cycle, to produce a ternary pulse train which is sampled by the timing pulses to reproduce the original binary pulse train. An error-rate sensor shifts the series of timing pulses by a half-cycle upon detecting any significant disalignment between them and the correct sampling instants.