Moderate deviations for joint source-channel coding of systems with Markovian memory

We study the (almost lossless) joint source-channel coding problem from the moderate deviations perspective where the bandwidth expansion ratio tends towards the ratio of the channel capacity and source entropy at a rate larger than n^-1/2 (n being the channel blocklength) and the error probability decays subexponentially. We consider the stationary ergodic Markov (SEM) source as well as discrete memoryless and additive SEM channels. We also discuss the loss due to separation in the moderate deviations setting.