Title :
Improved ADPCM voice transmission for TDMA-TDD systems
Author :
Nakamura, Osamu ; Dobashi, Akira ; Seki, Kazuhiko ; Kubota, Shuji ; Kato, Shuzo
Author_Institution :
NTT Radio Commun. Syst. Lab., Take, Yokosuka, Japan
Abstract :
Novel techniques are proposed to improve the adaptive differential pulse code modulation (ADPCM) voice signal transmission quality of time division multiple access-time division duplexing (TDMA-TDD) systems in fading environments. The proposed scheme employs an improved error detection technique with PCM signal differential detection and a cyclic redundancy code. Erroneous PCM bursts are replaced by error-free bursts. Hardware simulation results show that these techniques significantly improve ADPCM voice transmission quality in the fading environments typical of personal communication systems. The developed techniques enhance ADPCM voice transmission quality for cost effective personal communication systems
Keywords :
adaptive systems; cyclic codes; differential pulse code modulation; error detection; fading; personal communication networks; simulation; speech coding; time division multiple access; ADPCM voice transmission; PCM signal differential detection; TDMA-TDD systems; adaptive differential pulse code modulation; cyclic redundancy code; error detection; personal communication systems; time division duplexing; time division multiple access; voice transmission quality; Codecs; Costs; Cyclic redundancy check; Degradation; Fading; Hardware; Phase change materials; Signal detection; Signal processing; Working environment noise;
Conference_Titel :
Vehicular Technology Conference, 1993., 43rd IEEE
Conference_Location :
Secaucus, NJ
Print_ISBN :
0-7803-1267-8
DOI :
10.1109/VETEC.1993.507198
