  In this paper, we study the state-dependent two-user interference channel,
where the state information is non-causally known at both transmitters but
unknown to either of the receivers. We propose two coding schemes for the
discrete memoryless case: simultaneous encoding for the sub-messages in the
first one and superposition encoding in the second one, both with rate
splitting and Gel'fand-Pinsker coding. The corresponding achievable rate
regions are established.
