Analog joint source-channel coding over MIMO channels

Francisco J Vazquez-Araujo, Oscar Fresnedo, Luis Castedo, Javier Garcia-Frias
2014 EURASIP Journal on Wireless Communications and Networking  
Analog joint source-channel coding (JSCC) is a communication strategy that does not follow the separation principle of conventional digital systems but has been shown to approach the optimal distortion-cost tradeoff over additive white Gaussian noise channels. In this work, we investigate the feasibility of analog JSCC over multiple-input multiple-output (MIMO) fading channels. Since, due to complexity constraints, directly recovering the analog source information from the MIMO channel output
more » ... not possible, we propose the utilization of low-complexity two-stage receivers that separately perform detection and analog JSCC maximum likelihood decoding. We study analog JSCC MIMO receivers that utilize either linear minimum mean square error or decision feedback MIMO detection. Computer experiments show the ability of the proposed analog JSCC receivers to approach the optimal distortion-cost tradeoff both in the low and high channel signal-to-noise ratio regimes. Performance is analyzed over both synthetically computer-generated Rayleigh fading channels and real indoor wireless measured channels. infinite complexity and infinite delay. Indeed, when digital communication systems are designed to perform close to their theoretical limit, sources have to be compressed using powerful vector quantization (VQ) and entropy coding methods, and data has to be transmitted using capacity-approaching digital codes that make use of long block lengths. Thus, the suitability of the separation principle for the design of practical communication systems with severe constraints on delay and/or complexity is not clear. Discrete-time analog communication systems based on the transmission of continuous-amplitude channel symbols can be considered an attractive alternative to digital communication systems. For a lossy source-channel communication system to be optimal, the source distortion and the channel cost should lie on the optimal distortion-cost tradeoff curve. An example of such an optimal system is the direct transmission of discrete-time uncoded Gaussian samples over AWGN channels, both with the same bandwidth [3] . In this case, optimality arises because Gaussian sources are probabilistically matched to the AWGN channel. This idea is further explored in [4] where a set of necessary and sufficient conditions for any discrete-time memoryless point-to-point communication system to be optimal is provided. These conditions are satisfied not only by digital systems designed according to the separation principle but also by analog joint
doi:10.1186/1687-1499-2014-25 fatcat:mpo3qkawcbbkxd22f4oe2jhk4m