Title :
Burst-by-burst adaptive joint detection CDMA/H.263 based video telephony
Author :
Cherriman, P. ; Kuan, E.L. ; Hanzo, L.
Author_Institution :
Dept. of Electron. & Comput. Sci., Southampton Univ., UK
fDate :
5/1/2002 12:00:00 AM
Abstract :
Since wireless channels exhibit dramatic near-instantaneous channel-quality fluctuations, it is unrealistic to expect that a transceiver relying on time-invariant modulation and coding modes is capable of delivering as good a performance as a near-instantaneously adaptive arrangement. Hence, a near-instantaneously adaptive joint-detection code division multiple access (CDMA)-based video transceiver is proposed for wireless video telephony. Specifically, the transceiver is capable of reconfiguring itself in 1, 2 and 4 bits/symbol direct-sequence CDMA modes and delivers an unimpaired video quality associated with a peak signal-to-noise ratio (PSNR) of 34-41 dB for channel SNRs in excess of about 5 dB over the COST207 bad urban channel model at video rates between 5-26.9 kbits/s using 176×144 pixel quarter common intermediate format (QCIF) and 128×96 pixel sub-QCIF (SQCIF) video formats
Keywords :
adaptive modulation; adaptive signal detection; code division multiple access; mobile radio; quadrature amplitude modulation; spread spectrum communication; time-varying channels; transceivers; video coding; videotelephony; 128 pixel; 144 pixel; 176 pixel; 5 to 26.9 kbit/s; 96 pixel; DS-CDMA; H.263; PSNR; SNR; adaptive QAM; adaptive joint detection; adaptive quadrature amplitude modulation; mobile radio systems; peak signal-to-noise ratio; quarter common intermediate format; sub-QCIF; time-variant wireless channel; urban channel; video coding; video format; video telephony; video transceivers; Fluctuations; Modems; Multiaccess communication; Narrowband; PSNR; Quadrature amplitude modulation; Telephony; Transceivers; Video codecs; Wireless communication;
Journal_Title :
Circuits and Systems for Video Technology, IEEE Transactions on
DOI :
10.1109/TCSVT.2002.1003473
