PURPOSE: To eliminate the blocking of a relay function, by adjusting a phase amplitude adjusting circuit so that the correlation between a detected signal and a specific modulation signal can be zeroed and cancelling a detour signal between transmission and reception antennas.
CONSTITUTION: An output signal of a synthesizer 4 is modulated at a modulator 7 and a modulation signal generator 8, amplified 3 for relay and transmitted via a branching filter 5 and a transmission antenna 2. A normal signal out of signals inputted to the amplifier 3 is not subject to a low frequency amplitude modulation, but an interference signal and a feedback signal are subject to the low frequency amplitude modulation. A signal branched at a reception input branching filter 9 is envelope-detected 10 and components in correlation with the modulation signal from the generator 8 out of detected outputs are specified for the relation of phase and amplitude of the interference signal versus the feedback signal. When the correlation component is zero, both the signals are made to the opposite phase equal amplitude.
OKAMOTO SHIGEHARU
NOJIMA TOSHIO
NAKAJIMA NOBUO
NARA TAKEJI
