精选优质文档-倾情为你奉上SX simplex(transmission)单工传输FDX full-duplex 全双工HDX half-duplex 半双工 AM amplitude modulation 调幅FM frequency modulation调频PM phase modulation调相FDM frequency-division multiplexing频分复用TDM time-division multiplexing时分复用MA multiple access多路存取、多路访问CW continuous-wave连续波CDMA code-division multiple access码分复用PAM pulse amplitude modulation脉幅调制PCM pulse-code modulation脉码调制PPM pulse position modulation脉位调制PWM pulse width modula
