Distortion Tradeoffs of Different Layered Speech and Media Transmission Techniques Over Wireless MIMO Systems

The paper presents an analysis of strategies that combine layered source coding with various transmission strategies over point- to-point multiple input multiple output (MIMO) wireless systems. We are interested in the potential benefits/tradeoffs such systems have for the transmission of media. In doing so the paper necessarily considers two main issues. The first is to describe a measure/framework that can be used to generally guide the assessment of media (source) quality in the presence of outage events. The measure presented relates to traditional metrics but allows for more careful consideration of outage events. This allows for a more realistic assessment of the net media quality. Having such a measure is central to the MIMO investigation. The second issue is the optimization of media transport over wireless MIMO. With transmission systems one can explore with media (unlike data) the tradeoffs between media quality, the attempted transmission rate and the probability of outage events. With MIMO in particular we can consider adding diversity options enabled by layered source descriptions. The results suggest that MIMO transmission strategies that add diversity (linked to the source) can show benefits to media quality when compared to some media agnostic MIMO strategies that focus only on capacity.