Performance evaluation of 32 kbits/s real-time and dual-direction video communication system for wireless channels

Citation
N. Matoba et al., Performance evaluation of 32 kbits/s real-time and dual-direction video communication system for wireless channels, IEEE CIR SV, 11(5), 2001, pp. 664-672
Citations number
8
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Eletrical & Eletronics Engineeing
Journal title
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY
ISSN journal
1051-8215 → ACNP
Volume
11
Issue
5
Year of publication
2001
Pages
664 - 672
Database
ISI
SICI code
1051-8215(200105)11:5<664:PEO3KR>2.0.ZU;2-N
Abstract
This paper describes the construction and performance evaluation of a mobil e video communication system composed of an H.263 video encoder, decoder, a nd RF transceiver equipment. It can establish a video connection using a 32 kbits/s wireless channel because it uses automatic repeat request (ARQ) as the error control scheme, Retransmission control can produce excessive tra nsmission delay but the improved ARQ protocol and coding-rate control schem e adopted by this sl;stem minimizes the delay. This ARQ protocol uses short ARQ frame length and an acknwoledgement/negative acknowledgement (ACK/NAK) indicator. The coding-rate control scheme uses backward NAK signals to red uce the coding rate of the video encoder as necessary. We measure the trans mission delay characteristics of this video system and confirm that the pro posed scheme can reduce the delay over a noisy channel. Subjective assessme nt tests involving videophone usage are also conducted. Test results show t hat in a noisy channel (BER = 3 x 10(-3)) this system can achieve the same mean opinion score as in a noiseless channel.