Title :
Estimating unreliable packets in subband coded speech [digital mobile radio]
Author :
Wong, W.C. ; Seshadri, N. ; Sundberg, C.-E.W.
Author_Institution :
Dept. of Electr. Eng., Nat. Univ. of Singapore, Singapore
Abstract :
A robust digital mobile radio communication system using 12-kb/s embedded subband speech coding and rate-compatible punctured convolutional (RCPC) codes with generalized Viterbi decoding for combined error detection and correction is examined. Unreliable subband-coded speech side-information is identified and replaced using various estimation strategies. By using a realistic simulation model with 4-DPSK (differential phase-shift keying) modulation over a mobile channel, improvements of 1 to 4.4 dB in recovered speech segmental SNR (signal-to-noise ratio) are obtained compared to a system with only channel-based error correction. Informal subjective tests support these gains
Keywords :
decoding; digital radio systems; encoding; error correction codes; error detection codes; mobile radio systems; packet switching; phase shift keying; speech analysis and processing; 12 kbit/s; 4-DPSK; error correction; error detection; estimation; generalized Viterbi decoding; mobile radio channel; rate-compatible punctured convolutional codes; recovered speech segmental SNR; robust digital mobile radio communication system; simulation model; subband coded speech; unreliable packets; unreliable side-information; Convolution; Convolutional codes; Decoding; Differential phase shift keying; Error correction codes; Land mobile radio; Phase modulation; Robustness; Speech coding; Viterbi algorithm;
Conference_Titel :
Global Telecommunications Conference, 1990, and Exhibition. 'Communications: Connecting the Future', GLOBECOM '90., IEEE
Conference_Location :
San Diego, CA
Print_ISBN :
0-87942-632-2
DOI :
10.1109/GLOCOM.1990.116825
