RECEPTION METHOD AND RECEPTION DEVICE FOR SPREAD SPECTRUM COMMUNICATION SYSTEM

PROBLEM TO BE SOLVED: To provide a reception method and a reception device for a spread spectrum communication system capable of radio long distance communication by compensating deviation of a carrier frequency to remove limitation of making the bandwidth of a signal narrow.SOLUTION: A reception device 2 of the invention comprises: carrier frequency generation means 32; a matched filter 34 which is despreading means for despreading a reception signal frequency-converted by the carrier frequency; binary tree generation means 35 which divides the spread sequence of the reception signal to calculate a despreading vector for each partial sequence, turns the phase of the despreading vector by a certain angular to the positive or negative direction, branches out to two branches, and continues to branch out until the end of the spread sequence; maximum value detection means 36 which, in relation to a plurality of paths from the first to the last of the binary tree, calculates each norm of a combination despreading vector combining the despreading vector calculated for each partial sequence, and detects as despreading data a path about which the norm of the combination despreading vector becomes the largest among the plurality of paths; and demodulation means 38.