Capacity of a class of relay channel with orthogonal components and non-causal channel state

In this paper, a class of state-dependent relay channel with orthogonal channels from the source to the relay and from the source and the relay to the destination is studied. The two orthogonal channels are corrupted by common channel state which is known to both the source and the relay non-causally. The lower bound on the capacity for the channel is derived firstly. Then, we show that if the receiver output Y is a deterministic function of the relay input X_r, the channel state S and one of the source inputs X_D, i.e. Y = f(X_r, X_D, S), the explicit capacity can be characterized.