| 摘要 |
PURPOSE:To eliminate the noise of an incoming frequency band giving effect on the incoming line of the entire system caused by the transmission from the subscriber's equipment to the line by providing a recovery repeater for an incoming data signal to a distribution line and a drawing line to which subscriber's equipments are connected. CONSTITUTION:A recovery repeater 5 is connected between a subscriber's equipment 4 and a transmission line 2. The incoming data signal modulated to an incoming frequency band and the noise of the incoming frequency band are given to the demodulator 8 through a branching filter 6 and a band pass filter 7. The demodulator 8 detects the incoming data carrier to demodulate it into the base band and informs the carrier detection information 12 to the modulator 9. The modulator 9 is operated only when the carrier exists and modulates the demodulated signal again into the incoming frequency band and outputs the modulation signal to the transmission line 2 via a branching filter 10. Thus, the transmission of noise generated from the subscriber's equipment 4 to the transmission line 2 is prevented.
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