| 摘要 |
<P>PROBLEM TO BE SOLVED: To attain improvement in CNR by ensuring a dynamic range of optical transmission while suppressing the peak of an analog signal. <P>SOLUTION: If the amplitude of a reception signal S1 from an antenna 111 is greater than a prescribed threshold, a phase control unit 117 generates an opposite-phase signal attenuated in a prescribed ratio and a first adder 120 adds the signal S6 to a signal S5, thereby reducing the amplitude of a multiplexed signal S7. Furthermore, if the amplitude of the reception signal S1 from the antenna 111 is smaller than the prescribed threshold, the phase control unit 117 generates an in-phase signal S6 attenuated in the prescribed ratio and the first adder 120 adds the signal S6 to the signal S5, thereby enlarging the amplitude of the multiplexed signal S7. A second adder 121 multiplexes a phase control signal Sg and the signal S7 in frequency bands that are different from each other, the phase control signal Sg being indicative of a magnitude relation between the amplitude of the reception signal S1 and the prescribed threshold. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
