Entanglement-assisted classical communication over quantum channels for binary Markov sources

Abstract

Symbol-based iterative decoding is proposed for the transmission of classical Markov source signals over a quantum channel using a three-stage serial concatenation of a convolutional code (CC), a unity-rate code and a two-qubit superdense (SD) protocol. A modified symbol-based maximum a posteriori algorithm is employed for CC decoding to exploit the Markov source statistics during the iterative decoding process. Extrinsic information transfer chart analysis is performed to evaluate the benefit of the extrinsic mutual information gleaned from the CC decoder for sources with different correlations. We evaluate the bit error rate performance of the proposed coding scheme and compare it with the relevant benchmark schemes, including the turbo coding-based SD scheme. We demonstrate that a near-capacity performance can be achieved using the proposed scheme and when utilizing sources having a high correlation coefficient of $\rho =0.9$, the proposed coding scheme performs within 0.53 dB from the entanglement-assisted classical capacity.