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

Analogue joint source-channel coding (JSCC) has been shown to approach the optimal distortion-cost trade-off when transmitting over additive white Gaussian noise channels. In this work, we consider analogue JSCC over frequencyselective channels using orthogonal frequency division multiplexing (OFDM) modulation and multiple antennas at transmission and/or reception, that is, using a multiple input multiple output(MIMO)-OFDM system. Because of its high complexity, optimal Minimum Mean Square Error (MMSE) analogue JSCC decoding is infeasible in MIMO-OFDM systems and a practical two-stage decoding approach made up of an MMSE estimator followed by a maximum likelihood decoder is proposed instead. Three different alternatives for system optimisation are considered: non-adaptive coding, adaptive coding and adaptive coding with precoding. We show that the three considered strategies approach the optimal distortion-cost trade-off, but the best performance is obtained with the adaptive coding scheme when precoding is utilised. Copyright © 2014 John Wiley & Sons, Ltd.