Patent ID: 7724369

Claim:
A correlator comprising: a counter for receiving a pulse signal at given time intervals and counting the number of pulses; a sampling part for receiving the number of pulses counted by the counter; a delay part for receiving and sequentially delaying an output from the sampling part; an operation part for performing a product-sum operation of the output from the sampling part and the output delayed by the delay part for each channel; and a control part for setting a delay time or a sampling time T n for the channel n to T n =f n ×T o , where f n =a n−1 ×f n−1 +a n−2 ×f n−2 +a n−3 ×f n−3 + . . . +a 1 ×f 1 , a i ={0, 1}, and i=n− 1, n− 2, . . . , 1 (note that a series f n represents an integer geometric sequence of which a geometric ratio r asymptotically converges to 1≦r<2, and T o represents a unit sampling time defined by a base clock).