An improved algorithm for residual signal excitation based on LPC 10

Under narrowband shortwave communication conditions, digital speech coding is mostly in the form of low-rate linear predictive coding, but LPC parametric coding recovers low naturalness of speech with buzz. In this paper, we propose a method to improve the residual signal excitation based on LPC10. At the coding end, the prediction coefficients are solved based on linear prediction analysis, and the original speech is inverse filtered based on the prediction coefficients and differs from the original speech signal to obtain the residual signal; at the decoding end, the original muffled pulse excitation is replaced with the residual signal, and the improved synthesized speech improves the hum in the original LPC synthesized speech. The generated speech and the original speech are scored by PESQ algorithm, and the result showed that the improved speech score is 1.68, which is 0.34 points higher than the LPC 10 synthesized speech score.