The principles of source code and channel code are expatiated. The presentations of HDLC procedure, CRC, ARQ are given. The ECM transmission of the facsimile document is implemented on Visual C++ 6.0 platform.

• 详细阐述了信源、信道编解码原理，对HDLC规程、CRC校验、ARQ差错控制方式进行详细介绍，并在Visual C++6.；0平台上实现了传真报文的ECM方式传输。