Capacity of multiple access channels with correlated jamming

We investigate the behavior of two users and one jammer in an AWGN channel with and without fading when they participate in a non-cooperative zero-sum game, with the channel´s input/output mutual information as the objective function. We assume that the jammer can eaves-drop the channel and can use the information obtained to perform correlated jamming. Under various assumptions on the channel characteristics, and the extent of information available at the users and the jammer, we show the existence, or otherwise nonexistence of a simultaneously optimal set of strategies for the users and the jammer. Whenever the game has a solution, we find the corresponding user and jammer strategies, and whenever the game does not admit a solution, we find the max-min user strategies and the corresponding jammer strategy