说明：  1.由用户输入发射天线和接收天线的数量和SNR的值，画出MIMO通道性能的PDF和CDF,通道符合雷利分布。2.输入发射天线和接收天线数量及SNR范围，计算通道的性能，画出所有capacity v.s SNR图。
( ​ ​ 1. transmit and receive antennas are input by the user of the number and SNR draw MIMO channel performance of PDF and CDF, in line with Rayleigh distribution channel. 2. Enter the number of transmit and receive antennas and SNR range, computing performance channel draw all capacity vs SNR map.)