Title :
MIMO video broadcast via transmit-precoding and SNR-scalable video coding
Author :
Xu, Jun ; Hormis, Raju ; Wang, Xiaodong
Author_Institution :
Dept. of Electr. Eng., Shanghai Jiao Tong Univ., Shanghai, China
fDate :
4/1/2010 12:00:00 AM
Abstract :
Video transmission on multiuser wireless channels faces manifold challenges in both source- and channel-coding. We propose a framework to analyze three facets of this idea: video distortion, transmit power, and delay. In the scenario considered here, both the transmitter and end-users are equipped with multi-antenna transceivers. The goal is to broadcast video to all users; however, the video is differentiated in quality to match the spatial and temporal variation of the channel. An emerging coding standard that is well-suited to this scenario is the Scalable Video Coding (SVC) extension of H.264. We employ the medium-grain scalability (MGS) feature of SVC, which allows us to generate quality-scalable layers from a single video sequence. For transport, the transmitter employs the block-diagonal zero-forcing (ZF) precoding technique, a well-known technique which yields good performance. With these assumptions, the idea here is to compute a precoder at fixed intervals. Crucially, the cross-layer framework allocates layers of video to the end-users jointly with precoder computation. The framework also ensures that delay and buffer constraints are met, which is necessary for real-time video. In terms of solution approach, the problem turns out to be a difficult mixed-integer nonlinear optimization problem. However, we show that it is tractable via a primal-dual method. We analyze performance in various configurations, gaining insight into the relationship between the main system parameters.
Keywords :
MIMO communication; multi-access systems; precoding; transceivers; video coding; video communication; wireless channels; H.264 standard; MIMO video broadcast; block-diagonal zero-forcing precoding; coding standard; delay; medium grain scalability; multiantenna transceiver; multiuser wireless channel; real time video; scalable video coding; transmit power; transmit precoding; video distortion; video transmission; Broadcasting; Delay; MIMO; Multimedia communication; Nonlinear distortion; Scalability; Static VAr compensators; Transceivers; Transmitters; Video coding; MIMO; SVC; broadcast channels; precoding; quality layers; scalable video;
Journal_Title :
Selected Areas in Communications, IEEE Journal on
DOI :
10.1109/JSAC.2010.100416