Tomlinson harashima precoding for MIMO systemswith low resolution D/A-converters

We study the joint transmitter optimization for the flat multiinput multi-output (MIMO) channel under nonlinear distortion from the digital-to-analog converters (DACs). Our design is based on a minimum mean square error (MMSE) approach, taking into account the effects of the transmitter nonlinearities. The derivation does not make use of the assumption of uncorrelated white distortion (quantization) errors and considers the correlations of the quantization error with the other signals of the system. Through simulation, we compare the new optimized Tomlinson Harashima precoder to previously proposed transmitter designs when operating under DACs in terms of uncoded BER.