Matlab 模拟 CDMA 直接扩频。m序列生成矩阵为p(x) = 1 + x^5 + x^7 + x^8 + x^9 + x^13 + x^15。能画出每阶段的时域、频域图。-Matlab simulation of CDMA Direct Spread Spectrum. m sequence generated matrix for p (x) = 1+ x ^ 5+ x ^ 7+ x ^ 8+ x ^ 9+ x ^ 13+ x