Layered video multicast using diversity embedded space time codes
In traditional wireless multicast systems, the system is optimized to provide high reliability to users with the worst channel conditions. However this results in a waste of available bandwidth for users with a good channel conditions. In particular for transmission of video, this wasted bandwidth can be used to deliver higher quality video to some of the users. This paper addresses this problem by using diversity embedded space time codes (DESTC) to send multiple layers of video simultaneously. DESTC provides unequal error protection to different video layers, thereby delivering high quality video to users with good channel conditions while still providing acceptable quality to users with poor channel conditions. The performance of DESTC is compared to a single-layer orthogonal space-time code used for single-layer video delivery as well as layered video delivery with time division multiplexing. The results show that the use of DESTC is advantageous over both strategies in multicast video delivery.