| 摘要 |
In a speech signal encoding system comprising a maximum similarity series extracting unit (50) for producing a series of excitation pulses appearing at an equidistant time interval and an identical amplitude, the maximum similarity series extracting unit sums up, as a waveform, a series of autocorrelation coefficients to produce a series of summation result coefficients. The autocorrelation coefficients correspond to polarized pulses which are equal to one another in pulse interval and pulse amplitude. The polarized pulses form a plurality of pulse sequences which have phases different from one another. The maximum similarity series extracting unit extracts a polarity of each of the polarized pulses by the use of a dynamic programming method using a degree of an accumulated similarity as an evaluation measure and selects, as the excitation pulse series, one of the pulse sequences which has a maximum waveform similarity between the summation result coefficient series and a series of cross correlation coefficients. |
