A set of consecutive digit time slots in which the position of each digit time slot can be identified by reference to a frame alignment signal. 一組連續的數字時間片段，每一數字時間片段在組內的位置可參考幀同步信號來標識。
Experiments show that this method can implement the frame synchronization head detection, and thus realize the correct de-multiplexing of the digital signals. 實驗表明，此方案成功地在光纖通信系統的接收端檢測到幀同步信號，從而實現了數據的正確分接。
