Performance of UWB Impulse Radio in strong MAI with frequency offsets estimation

This paper investigates the performance of a coherent receiver for ultra-wide-band Impulse Radio. Specifically, we suppose that the useful signal is affected by a dispersive channel and that the receiver collects also multiple access interference (MAI), while experiencing frequency drifts due to clock mis-alignments. Building upon a Gaussian mixture (GM) model for MAI, the receiver uses a space alternating generalized expectation maximization (SAGE) estimation approach for all unknowns quantities: channel, frequency offsets, and data. Iterative and adaptive algorithms are formulated. The latter enables a low-complexity implementation of the whole estimation procedure with small performance loss. The provided simulations are a first step in evaluating the performance of a receiver coping with all the most critical uncertainties at the same time.