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在发射机和接收机的整个系统中,音频信号调制一个射频信号,已调信号经滤波产生一个具有给定频宽的单边带信号,采用单边带信号同只有该信号频宽几分之一的信号混频、外差的方法,对单边带频宽进行压缩,由此获得的频带被压缩了的单边带信号经由线路传输到接收机.在接收机里,采用一个较高频率的信号同接收到的单边带信号混频外差的方法以及采用从接收机输入端得到的一个信号同该较高频率信号混频、外差方法,把单边带信号的频宽扩展到原来未被压缩时的信号频宽.这个系统容许传输一个频宽为最初调制信号频宽1/4的单边带信号.
In the entire system of transmitter and receiver, the audio signal modulates a radio frequency signal, the modulated signal is filtered to produce a single sideband signal of a given bandwidth, and a single sideband signal is used with a fraction of the signal bandwidth A signal mixing, heterodyne method, the bandwidth of the single sideband is compressed, the resulting band is compressed by the single sideband signal transmitted to the receiver through the receiver in the use of a higher frequency And the received single-sideband signal, and a signal obtained from the input of the receiver is mixed with the higher-frequency signal. The heterodyne method expands the bandwidth of the single-sideband signal to The original uncompressed signal bandwidth allows the system to transmit a single-sideband signal with a bandwidth of 1/4 of the original modulated signal bandwidth.