| 摘要 |
<P>PROBLEM TO BE SOLVED: To carry out inverse spread demodulation by using a spread code generating circuit without need for any externally mounted component and any synchronization control. <P>SOLUTION: The inverse spread demodulator includes: a first spread code generating circuit for generating spread codes; a second spread code generating circuit for generating spread codes rearranged in an opposite direction; a polarity conversion circuit 101 for converting the spread codes in a way that nearly a half the spread codes corresponding to new or old spread signals of which indicate inverting and noninverting states for one period of a clock f2; a hold circuit 108 for holding an adder output when nearly half the spread codes are inverted; a second peak detector 109 for calculating an absolute sum between the adder output when nearly half the spread code is not inverted and an output of the hold circuit to detect a peak; and a spread code control circuit for alternately switching a spread code input from the first spread code generating circuit to the polarity conversion circuit, and input of the spread code from the second spread code generating circuit to the polarity conversion circuit, every time the peak is detected. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
