| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a demodulator which can detect an adjacent channel disturbance. <P>SOLUTION: A second signal level detector 202 has characteristics in which, when an input signal level becomes lower than a desired signal level, an output becomes larger. A frequency component out of a passing band exists in the input signal of a third filter 115 in the state that the adjacent channel disturbance exists. In such case as interference exists in an adjoining channel, the frequency component out of the passing band exists in the input signal of the third filter 115. The frequency out of this passing band is cut off by the third filter 115, the signal level of the output of the third filter 115 becomes lower than the input signal. Accordingly, the output of the second signal detector 202 becomes large, and it is understood that an adjacent channel disturbance exists. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
