Adaptive multi-rate wideband( AMR-WB) is a high-quality wideband voice encoding technology,in which full searching( FS) algorithm is commonly used in vector quantification. The FS algorithm has relatively high accuracy,however,the computation is complex and the search speed is slow. To solve the defects mentioned above,the authors propose a improved vector quantification codeword search algorithm,in which the partial distortion search algorithm is introuced and the setting of its initial matching codeword i...