摘要 |
PURPOSE:To increase the degree of freedom of the selection of a synchronous pattern and to simplify a synchronous detecting method by transmitting a block-synchronizing flag and block data following it from a frame-synchronizing position successively. CONSTITUTION:Synchronizing flags of data blocks each consisting of (n) bits are transmitted from time slots in phase with a frame-synchronizing bit #1. One frame consists of (m) time slots, and n>m, so one block is transmitted by using more than one frame. When one-block data is transmitted and then there is no data block to be transmitted next, an idle pattern is sent to a transmission line and when transmitted data is generated, the next block is sent from the earliest frame-synchronizing position (#l-1). At a reception side, the detecting operation for the synchronizing flag is started at a frame-synchronizing position and when the synchronizing flag is detected, the synchronizing-flag detection operation is interrupted during the period of block data reception. Once the idle pattern is detected, the operation is restarted. |