各种数字调制解调方法的MATLAB实现，输出为信噪比图像。包括BPSK,DPSK,QAM,QPSK(包括有无格雷编码的对比)-A variety of digital modulation and demodulation MATLAB implementation of the method, the output SNR images. Including BPSK, DPSK, QAM, QPSK (including comparative Have Gray coding)