Characterization of Rate Region in Interference Channels with Constrained Power

In this paper, an n-user Gaussian interference channel under arbitrary linear power constraints is considered. Using Perron-Frobenius theorem, a closed-form expression for the boundary points of the rate region of such a channel is derived. This is a generalization of the well-known result on the maximum rate that some interfering links can simultaneously achieve when the power is unbounded. Moreover, this result is extended to the time-varying channels with constraints on the average power.