AWGN-Rayleigh-BPSK-DSSS(BPSK调制解调直接序列扩频系统源代码(白噪声及瑞利衰落误码率比较)并给出误码率曲线的程序-AWGN-Rayleigh-BPSK-DSSS (BPSK direct sequence spread spectrum modulation and demodulation system source code (white noise and Rayleigh fading error rate comparison) and the procedu