| 摘要 |
<P>PROBLEM TO BE SOLVED: To control an amplification factor so as to allow a reception signal to have an optimum amplitude. <P>SOLUTION: An antenna 64 receives the reception signal, and a VGA 77 amplifies the reception signal by a first amplification factor. An amplifier 75 amplifies the signal outputted from the VGA 77 by a second amplification factor. An amplifier 78 performs amplification by a third amplification factor which is obtained by multiplying the second amplification factor by a prescribed coefficient. A comparator 76 outputs output data based on a comparison result after comparing a peak value of the signal outputted from the amplifier 75 with a prescribed threshold. A comparator 80 outputs comparison data, based on the comparison result after comparing the peak value of the signal outputted from the amplifier 78 with a threshold identical to that of the comparator 76. An AGC circuit 81 controls the first amplification factor based on a count value being the number of times of the level transition of comparison data in a prescribed period. The present invention can be applied to a communication apparatus, for example. <P>COPYRIGHT: (C)2009,JPO&INPIT |
