Encoder Reverberations in Adaptive Predictive Coding

作     者：Mills, James D. Rohrs, Charles E. Magill, Robert B. 

作者机构：Tellabs Res Ctr Mishawaka IN 46545 USA 

出 版 物：《IEEE TRANSACTIONS ON SPEECH AND AUDIO PROCESSING》 (IEEE Trans Speech Audio Process)

年 卷 期：1994年第2卷第1期

页      面：18-23页

核心收录：

主　　题：Reverberation Predictive coding Quantization Decoding Milling machines Speech analysis Predictive models Nonlinear distortion Robustness Delta modulation 

摘      要：In the past, the nonlinear effects of quantization in differential speech coders either were modeled as additive white Gaussian noise or were ignored in analysis and quazntified experimentally. Describing functions are used to model the nonlinear quantizer effects of coarsely quantized difference signals found primarily in adaptive predictive coding (APC) systems. The analysis predicts marginal instabilities in APC encoders. The marginal instabilities result in ringing distortions in the reconstructed signal which, in the past, may have been attributed to pitch and spectral predictor mismatches. Adaptive order prediction is introduced, analyzed, and offered as a method for increasing the robustness of APC encoders.