代码实现了一个根升余弦成型滤波器，2PAM信号通过此成型滤波器，并且匹配接收，画出了发送和接收波形，验证了代码的正确性。-The code designs a root raised cosine filter,2PAM signal transmitted through the filter and matched using the same filter, I plot the transmitted signal and received signal to verify the correctness of the code.