| 摘要 |
The TDM cable transmission system samples the input analogue signals and converts the samples into pulse-position modulated (P.P.M.) signals. The P.P.M. signals are converted at the transmitter into rectangular waveforms whose edges are position-modulated. At the receiver the signal passes over a low pass filter having a Gaussian transfer function and consisting of the cable itself, an amplifier and a regenerator. The rectangular wave is converted back into the P.P.M. signal and the P.P.M. signal then converted back into the analogue signal. The transmission system has a bandwidth that is narrower than normal for P.P.M. systems. |
