Efficient Connectivity Topologies for Networked Control Systems

This paper presents a perceptually optimized joint source/channel coding scheme for video transmission over satellite broadcast channel. We express the end-to-end expected distortion in terms of the source coder distortion and the channel distortion. Perceptual distortion model just-noticeable-distortion (JND) is applied to improve the subjective quality of compressed video. 3-D wavelet video codec that is jointly optimized with channel codec can remove spatial and temporal redundancy and provide the scalability of video quality for broadcast channel. In order to conceal the errors under bad channel conditions and prevent the error propagation of arithmetic decoding, slicing method and a channel coding scenario that combines RCPC, Reed-Solomon codes and CRC are proposed. Two perceptual distortion indices based on JND are discussed. These two indices are combined in our joint source/channel coding scenario to achieve minimal bandwidth consumption subject to acceptable visual quality under normal and bad channel conditions. Computer simulation is conducted at difference signal-to-noise ratios (SNR). Our system uses offset QPSK (OQPSK) modulation scheme to combat the nonlinear effect of satellite channels. Acknowledgment: Research supported by the Communications and Networks Consortium sponsored by the U. S. Army Research Laboratory under the Collaborative Technology Alliance Program, Cooperative Agreement DAAD19-01-2-0011, and by the ARO MAASCOM MURI, grant W911NF-08-1-0238.