Characterization of Rate Region in Interference Channels with Constrained Power

In this paper, an $n$-user Gaussian interference channel, where the power of the transmitters are subject to some upper-bounds is studied. We obtain a closed-form expression for the rate region of such a channel based on the Perron-Frobenius theorem. While the boundary of the rate region for the case of unconstrained power is a well-established result, this is the first result for the case of constrained power. We extend this result to the time-varying channels and obtain a closed-form solution for the rate region of such channels.Comment: 21 Pages, The Conference Version is Submitted to IEEE International Symposium on Information Theory (ISIT2007

Optimal Order of Decoding for Max-Min Fairness in KK-User Memoryless Interference Channels

A $K$-user memoryless interference channel is considered where each receiver sequentially decodes the data of a subset of transmitters before it decodes the data of the designated transmitter. Therefore, the data rate of each transmitter depends on (i) the subset of receivers which decode the data of that transmitter, (ii) the decoding order, employed at each of these receivers. In this paper, a greedy algorithm is developed to find the users which are decoded at each receiver and the corresponding decoding order such that the minimum rate of the users is maximized. It is proven that the proposed algorithm is optimal.Comment: 11 Pages, Submitted to IEEE International Symposium on Information Theory(ISIT 2007