| 摘要 |
PURPOSE: To avoid the complexity of a circuit accompanying the increase in throughput by eliminating the problem that a CDMA system received frame synchronizing circuit causes nondetection or misdetection of a synchronizing code in noise or multipath environment. CONSTITUTION: A path detecting circuit 11 extracts timing of each path at each symbol timing point of a received reverse spread signal and separately output it on a time base. Each timing point is regarded as a trigger point and a reverse spread signal at each timing point is stored in (n) latches 121-12n. Then 1st-(n)th path correlation arithmetic parts 141-14n are provided to perform correlation with the output of a synchronizing word register 13 at each timing of a path and output respective correlation values, which are put together by a composition part 15 and then decided by a decision circuit 16; and a frame timing detecting circuit 17 detects frame timing. A 1st path correlation arithmetic part 141 is always in processing and others are allowed to perform processing only when there is frame timing. |
