On capacity computation for the two-user binary multiple-access channel: Solutions by cooperation

This paper deals with the computation of the boundary of the capacity region for the two-user memoryless multiple-access channel, which is equivalent to solving a difficult non-convex optimization problem. We study properties of the optimality conditions for a relaxation (cooperation) approach suggested in the literature. We give conditions under which a solution to the relaxed problem has the same value as the actual optimal solution and show that these conditions can in some cases be applied to construct solutions for a restricted class of discrete multiple-access channel using convex optimization.