— This paper proposes a numerical method for characterizing the achievable rate region for a Gaussian multiple access channel with ISI under the frequency division multiple access restriction. The frequency spectrum is divided into discrete frequency bins and the discrete bin assignment problem is shown to have a convex programming relaxation, making it tractable to numerical algorithms. The run-time complexity may be further reduced in the two-user case if the two channels are identical, or if the signal-to-noise ratio is high.
Wei Yu, John M. Cioffi