Patent ID: 7003022

Claim:
A matched filter for obtaining a correlation between a signal received through a multipath transmission line and a spreading code sequence, comprising: N partial filters, each partial filter having a predetermined number m of taps, that are serially connected; first adder means for adding outputs of activated partial filters from among the N partial filters; control means for dividing, based on a time width of effective paths included in the received signal, the spreading code sequence into subsequences, each subsequence having m chips, activating n partial filters from among the N partial filters, wherein n satisfies n*m*Ts≧Td>(n−1)*m*Ts, where Ts represents a sampling period of the received signal and Td represents a maximum delay time of the multipath signal, and supplying the subsequences to the n activated partial filters; end second adder means for integrating outputs of the first adder means; wherein N, m, and n are integers; m≧2; and N≧2; n≧1.