GAME THEORY FOR PRECODING IN A MULTI-USER SYSTEM: BARGAINING FOR OVERALL BENEFITS

A precoding strategy for multi-user spectrum sharing over an inter-ference channel is proposed and analyzed from a game-theoretic per-spective. The proposed strategy is based on finding the Nash bar-gaining solution for precoding matrices in a cooperative scenario over frequency selective channels under a spectrum mask constraint. An in-time update of the precoding matrices is enabled by using time slots to guarantee the effectiveness of the bargaining solution when the number of users varies. A dual decomposition approach is ex-ploited to construct a distributed structure for solving the bargaining problem. The proposed distributed algorithm realizes the physical process of bargaining, which is not present in the Nash bargaining theory. Index Terms — Linear precoding, interference channel, Nash bargaining, cooperative game, duality, dual decomposition