Please use this identifier to cite or link to this item:
|Title:||Estimation of unreliable packets in subband coding of speech|
|Authors:||Wong, W.C. |
|Source:||Wong, W.C.,Seshadri, N.,Sundberg, C.-E.W. (1991-02). Estimation of unreliable packets in subband coding of speech. IEE Proceedings, Part I: Communications, Speech and Vision 138 (1) : 43-49. ScholarBank@NUS Repository.|
|Abstract:||A robust speech communications system over a digital mobile radio channel is considered. We examine a system using 12 Kbit/s embedded subband coding of speech and rate compatible punctured convolutional (RCPC) codes with generalised Viterbi decoding for combined error detection and correction. System performance is improved by exploiting the frame-to-frame redundancy in the subband energy profile used for adaptive bit allocation in the subband coder. Unreliable subband side information about the energy profile is identified through a two-stage process comprising the channel error detector and a source-based subband energy profile error detector. The subband side information deemed unreliable is replaced with the estimates based on frame-to-frame redundancy. This improved error detection capability in the subband side information allows a judicious reassignment of channel error protection bits to the subband main information, leading to an overall improvement in system performance. Using a realistic simulation model of a digital mobile radio communication system, an improvement of up to 4.4 dB in recovered speech segmental SNR is obtained at a channel SNR of 6 dB, compared with a system with only channel error protection.|
|Source Title:||IEE Proceedings, Part I: Communications, Speech and Vision|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Dec 15, 2017
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.