| 摘要 |
PURPOSE:To smooth the system operation by multiplexing a signal of plural subscribers and transmitting the result and changing the transmission capacity of the transmission line in response to the traffic on the transmission line so as to decrease the effect due to noise and attenuation of rainfall. CONSTITUTION:A multiplexer 2 of the communication system recognizes the presence of a subscriber signal from a signal input terminal 1 and applying multiplexing to the subscriber signal only, and the result is fed to a variable capacity modulator 3. The modulator 3 brings the multiplexing signal into a narrow band signal of a transmission capacity C1 and applies it to a variable capacity demodulator 4 at the reception side. A clock extraction circuit 10 of the demodulator 4 detects the increase/decrease in the input clock number at an input point (a). Then a variable band filter 8 and a demodulator 9 are controlled depending on the clock number in response to the subscriber's traffic to output a signal received at the optimum band at an output point (b). The signal is distributed to a signal output terminal 6 by using a multiplexer 5 so as to reduce the effect on the system due to noise and rainfall attenuation. |
