Orthogonalization search for the CELP based speech coding

摘要

A dispersed vector generator used for speech encoder or a speech decoder to improve a speech quality comprising a pulse vector providing section that provides a pulse vector having a signed unit pulse on one element of a vector axis, a dispersion pattern determining section that determines a dispersion pattern out of the set of waveforms predefined before starting the processing of encoding or decoding, and a dispersed vector generating section that convolutes said pulse vector and said determined dispersion pattern to generate a dispersed vector wherein a length of said waveforms is shorter than a length of a sub-frame.