| 摘要 |
PROBLEM TO BE SOLVED: To reduce the effect of interference between a transmission circuit and a reception circuit and between reception circuits by controlling an oscillating frequency of a prescribed local oscillation circuit among a plurality of local oscillation circuits in response to a required discrimination result. SOLUTION: A storage device 18 stores either or both of a transmission reception channel where intermediate frequencies for transmission/reception are overlapped and a reception channel where an intermediate frequency of a reception signal is overlapped with any of harmonics of a local oscillation circuit used for a demodulator 13 of a circuit of a reception system. Furthermore a controller 17 controls oscillated frequencies of a 1st reception local oscillator 7, a 2nd reception local oscillator 12, a modulator use local oscillator 16 and a transmission local oscillator 8 so as to avoid intermediate frequencies for the terminal and reception from being overlapped in the case that a required channel is selected. Through the control above, the effect of interference on a reception characteristic of the transmission intermediate frequency and the effect of interference on a harmonic reception characteristic of the local oscillation circuit of the demodulator in the reception system circuit are reduced to prevent deterioration in the reception characteristic.
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