说明：  调制信号解调时，从解调出的信号中提取码元同步时钟，以获得最佳的抽样判决时刻。本程序采用超前-滞后同步法，计数器时钟为16倍的码元时钟。 该程序同步效果很好，已使用在项目中。
(Demodulating the modulated signal, extracts the symbol clock from the synchronizing signal demodulated in order to obtain the best sampling time judgment. This program uses a lead- lag synchronization method, counter clock is 16 times the symbol clock. The program works well synchronized, have been used in the project.)