Patent ID: 8515743

Claim:
A method for searching a fixed codebook, comprising: obtaining a basic codebook, the basic codebook comprising initial position information of N pulses on M tracks, wherein each of the M tracks comprises multiple positions, and wherein N and M are positive integers; in a search round, repeating the following search process for K times: (1) choosing, from the basic codebook, n pulses from the N pulses as search pulses, wherein n is a positive integer smaller than N; and (2) replacing each of initial positions of the n search pulses with a different position on the same track, so as to obtain a searched codebook; wherein K is a positive integer larger than or equal to 2, at least two search pulses are chosen in at least one of the K search processes, the at least two search pulses are distributed on different tracks, and the search pulses vary with each search process; choosing an optimal codebook from the basic codebook and the K searched codebooks according to a preset criterion; and replacing the basic codebook with the optimal codebook as a basic codebook for a next search round.