Optimal HDA Schemes for Transmission of a Gaussian Source Over a Gaussian Channel With Bandwidth Compression in the Presence of an Interference

We consider transmission of a Gaussian source over a Gaussian channel under bandwidth compression in the presence of an interference known only to the transmitter. We study hybrid digital-analog (HDA) joint source-channel coding schemes and propose two novel layered coding schemes that achieve the optimal mean-squared error (MSE) distortion. This can be viewed as the extension of results by Wilson [“Joint Source Channel Coding With Side Information Using Hybrid Digital Analog Codes,” IEEE Trans. Inf. Theory, vol. 56, no. 10, pp. 4922-2940, Oct. 2010], originally proposed for sending a Gaussian source over a Gaussian channel in two cases: 1) Matched bandwidth with known interference only at the transmitter and 2) bandwidth compression where there is no interference in the channel. As the main contribution of this work, we provide optimal power allocation strategies for the proposed HDA schemes which enable us to cancel the channel interference and obtain the “optimum performance theoretically attainable” (OPTA) of additive white Gaussian noise (AWGN) channel with no interference in the case of bandwidth compression. We also provide performance analysis in the presence of signal-to-noise ratio (SNR) mismatch where we expect that HDA schemes perform better than strictly digital schemes.