| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an automatic amplitude control circuit which can accurately perform control under any control conditions. <P>SOLUTION: This automatic amplitude control circuit comprises a multiplier 13, a low-pass filter 14, a comparator 15, a 1st absolute value circuit 16 and a 2nd absolute value circuit 18, and a delay circuit 17. The multiplier 13 multiplies the signal outputted by the low-pass filter 14 by a 1st orthogonal signal Ich. The 1st absolute value circuit 16 finds the amplitude of the 1st orthogonal signal Ich outputted by the multiplier and the 2nd absolute value circuit finds the amplitude of a 2nd orthogonal signal Qch. The delay circuit sends the output signal from the 2nd absolute value circuit with a delay of at least one symbol. The comparator compares the amplitude of the 1st orthogonal signal with the amplitude of the 2nd orthogonal signal after the output signal is delayed by the delay circuit. <P>COPYRIGHT: (C)2003,JPO |
