Digital transmission system.

摘要

The invention concerns a terminal for a telephone system and for receiving digital data in the form of a time multiplexed (TDM) data stream incorporating frames appearing at a predetermined frame period and each frame incorporating a frame word. The terminal comprises frame word detecting means (52) for detecting frame words; alignment detecting means (53, 55, 56) for determining whether a received TDM data stream is in alignment or not; search means (53, 55, 56, 57, 59, 60) for initiating a bit-by-bit search of the incoming data stream for the sequence of bits forming the frame word when an "out-of-alignment" condition has been detected by the said alignment detecting means; and delay means (58) for delaying the start of the bit-by-bit search after an "out-of-alignment" condition has been detected.