Minimal-rate description for multiple-access channels

In this paper we consider the problem of a two-user multiple-access channel that is different from the conventional one. We require the receiver to provide only a reliable information-mixture of the incoming messages from the two users, not the exact contents. The minimum rate of such mixture is termed the minimal description rate of the channel output. Answers to this problem have many potential applications to the latest network-coding-based wireless communication networks. Exact capacity regions of a class of fading multiple-access channels are determined, along with the corresponding deterministic capacity-achieving coding schemes.