通信系统包括pcm，hdb3编码和译码，最佳接收机ask，qpsk，fsk调制方式-The communication system includes pcm, hdb3 encoding and decoding, the best receiver ask qpsk, FSK modulation mode

生成一个随机序列，然后对其进行HDB3编码，最后对其解码，显示出来-Generating a random sequence, then subjected HDB3 encoding, and finally decodes, displayed