| 摘要 |
PURPOSE:To realize a 1-frequency system with excellent frequency utilizing efficiency by using an output of a phase difference detector to control a variable frequency oscillator. CONSTITUTION:The one-frequency repeater is operated by a transmitter 4, a receiver 5 and antennas 8, 9. Further, the subtractor 3 subtracts an output of the multiplier 2 being the multiplication of -alpha with an output of the frequency shifter 1 from the sum between the interference of transmission and reception and a normal reception signal in order to eliminate the interference corresponding to the quantity alpha of interference between transmission and reception. In this case, in applying interference from a transmission carrier deviated largely from a reception carrier to a filter of the receiver 5, the edge of the band of the interference signal is cut off by the filter of the receiver to cause waveform distortion. Then a phase difference detector 100 and a variable frequency oscillator 202 constitute a phase locked loop, which is synchronized with a variable frequency oscillator 302 of the reception side. Thus, both the carrier frequencies of transmission and reception are made coincident to exclude the said waveform distortion. |
