State-Dependent DMC with a Causal Helper

A memoryless state sequence governing the behavior of a state-dependent channel is to be described causally an encoder wishing communicate over said channel. Given maximal-allowed description rate, we seek that maximizes Shannon capacity. It shown maximum need not achieved by (symbol-by-symbol) description. Such descriptions are, however, optimal when receiver cognizant or allowed depend on message. For other cases, block-Markov scheme with backward decoding proposed.