On sliding block coding for transmission of a source over a stationary nonanticipatory channel

It is shown that the capacity Cb of a stationary nonanticipatory channel with respect to block coding is at least as great as the capacity Cs of the channel with respect to sliding block coding. For several types of stationary nonanticipatory channels (namely, ergodic channels, channels with additive random noise, and averaged channels whose components are discrete memoryless channels), it is shown that Cb = Cs, thereby generalizing a result of Gray and Ornstein for the discrete memoryless channel