| 摘要 |
<p>A data transmission system is disclosed which comprises a source of a data signal and a modulator, responsive to the data signal, producing a first modulated signal representing the data signal and a second modulated signal representing a signal (180 second modulated signals are transported via a transmission channel. A first demodulator (50, 100) demodulates the transported first modulated signal and a second demodulator (50, 100) demodulates the transported second modulated signal. A subtractor (60, 70), responsive to the first and second demodulators, produces a signal representative of the data signal.</p> |
