Multiple Access Channels With States Causally Known at Transmitters
The state-dependent Multiple Access Channel (MAC) is considered where the state sequences are known causally to the encoders. First, a MAC with two independent states each known causally to one encoder is revisited, and a new achievable scheme inspired by the recently proposed noisy network coding is presented. This scheme is shown to achieve a rate region that is potentially larger than that provided by recent work for the same model. Next, capacity results are presented for a class of channels that include modulo-additive state-dependent MACs. It is shown that the proposed scheme can be easily extended to an arbitrary number of users.