Adaptive Video Transmission over Wireless MIMO System

There has been an interesting issue in multimedia communications over wireless system in recent years. In order to achieve high data rate wireless multimedia communications, spatial multiplexing technique (Foschini & Gans, 1998; Wolniansky et al. 1998) has recently developed as one of the most noteworthy techniques as multiple-input and multiple-output (MIMO) systems. If the channel state information is perfectly available at the transmitter (Driessen & Foschini, 1999; Burr, 2003), we can maximize the channel capacity to design a realizable video transmission system. Under channel capacity limitation, the chapter presents how to employ joint source-channel coding algorithm with adequate modulation techniques to get the possibly best performance in the system design. Adaptive video coding to the varying channel conditions in real-time is well matched to MIMO systems for an optimized video transmission. An important matter in designing adaptive video transmission system is how often the feedback of the channel state information should be carried out. In fact, the feedback interval is mainly decided by the channel characteristics. For wireless fading channels, the feedback information needed to be able to capture the time varying channel characteristics for a true adaptive transmission. Song & Chen (2007, 2008) proposed adaptive algorithm design to utilized partial channel state information from receiver for layered scalable video coding (SVC) transmission over MIMO system. There are some interesting topics related in adaptive video transmission over wireless multimedia communication systems can be found in (Chen & He, 2006). In our proposed system, we investigate the system performance of a joint MPEG-2 coding scheme with convolutional channel coding and space time block coding (STBC) techniques, associated with suitable modulation method (BPSK or QPSK), for video data transmission over a wireless MIMO system with Rayleigh fading noises. Rates assigned to MPEG-2 source code and convolutional channel code as well as space-time block code schemes are based on the feedback information from Performance Control Unit (PCU) under system channel capacity limitation, which ensures the proposed system achieved the best performance compared to a conventional designed system. In a conventional way, source coding and channel coding are designed to accomplish the best system performance respectively. With simply combining the best source coding scheme with the best channel coding scheme together, the system does not promise a better overall performance.