Analog joint source-channel coding over MIMO channels

Abstract

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 is 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.

Analogue joint source‐channel coding for multiple input multiple output–orthogonal frequency division multiplexing systems

“…The advantage of such approach is that performance approximates the optimal distortion-cost trade-off in the whole CSNR region while keeping complexity and delay at a minimum [17]. Recently, we have successfully applied this receiver structure to the case of MIMO transmission systems, where the use of the optimal MMSE decoding is clearly infeasible [9,17]. In Section 3 , we will also corroborate that this approach also attains excellent performance in MIMO-OFDM systems.…”

“…As an example, references consider the use of spatial diversity to improve the performance of analogue JSCC in wireless fading channels. Another example is , where the transmission of analogue samples over single‐carrier multiple input multiple output (MIMO) fading channels is considered. It is also worth mentioning reference where the implementation on a software‐defined radio testbed of a wireless system based on analogue JSCC is presented.…”

Evaluation of Analog Joint Source-Channel Coding Systems for Multiple Access Channels

“…Nevertheless, most works in the literature focus on analog JSCC over Gaussian channels. Some exceptions are the evaluation of analog JSCC over Rayleigh fading channels [11], and the design of analog MIMO JSCC systems for flatfading channels [12] and frequency-selective channels using an OFDM modulation [13]. Although the Shannon-Kotel'nikov mappings employed for these analog JSCC systems are actually optimal for AWGN channels, the results obtained in these works also confirm their utility for fading channels and wireless communications.…”

“…On the other hand, given that the analytical optimization of δ i is very difficult when α i = 2 [7], the optimum values for δ i can be also determined by off-line computer simulations. The obtained values can be looked up in the tables presented in [12].…”

“…Given that the objective is the sum-distortion minimization, CSI can be exploited to obtain the linear access codes that minimize the sum-MSE between the input and output of the channel. This is a reasonable approach if we have in mind that linear MMSE filtering together with ML decoding performs extremely well in point-to-point communications [12], [24].…”