An error correction approach based on maximum likelihood estimation combined with hidden Markov models
✍ Scribed by Tadashi Yonezaki; Koji Yoshida; Toshio Yagi; Kiyohiro Shikano
- Publisher
- John Wiley and Sons
- Year
- 2002
- Tongue
- English
- Weight
- 306 KB
- Volume
- 85
- Category
- Article
- ISSN
- 1042-0967
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
This paper proposes an error‐correction algorithm for channel error using the hidden Markov model (HMM). The proposed method uses two probabilities calculated by the information source model (HMM) and the channel model, under the constraint of the received code sequence, and estimates the transmitted code sequence by maximum likelihood. Consequently, the robustness to error can be improved without adding error‐correcting code by applying the proposed method to the preprocessing of the existing code system. Using the code sequence obtained by quantizing the LSP parameters, the reduction of cepstrum distortion in error correction by the proposed method is examined. It is found that the distortion can be reduced by approximately 39% by the proposed method (16‐state HMM) for a code sequence with 3% random errors. © 2002 Scripta Technica, Electron Comm Jpn Pt 3, 85(5): 63–71, 2002