2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/222165The sum-rate capacity of the parallel Gaussian interference channel is shown to be achieved by independent transmission across sub-channels and treating interference as noise in each sub-channel if the channel coefficients and power constraints satisfy a certain condition. The condition requires the interference to be weak, a situation commonly encountered in, e.g., digital subscriber line transmission. The optimal power allocation is characterized by using the concavity of sum-rate capacity as a function of the power constraints.32 pages, 8 figures, submitted to IEEE trans. on Information Theory in FebInformation Theorytext