Transmit Precoding for MIMO-BICM-ID Satellite Systems with Nonlinear Power Amplifiers

For power efficiency, High Power Amplifiers (HPAs) used in satellite communications must be operated as close as possible to saturation. This constraint especially results in nonlinear amplitude distortions of the transmit signals. In this paper, the impact of these distortions on the performance of a linearly precoded 2 x NR Multiple-Input-Multiple-Output (MIMO) Single Carrier Geostationary Earth Orbit (GEO) satellite system operated for fixed satellite services (FSS) and using PSK modulation is analyzed. In order to combine channel coding and modulation, a Bit-Interleaved-Coded-Modulation with Iterative Decoding (BICM-ID) scheme is considered. Through EXIT charts and BER simulations, it is shown that a phase precoder which aims at maximizing the input-output mutual information and doesnt increase the Peak-to-Average-Power-Ratio (PAPR) of the transmit signals, is a robust strategy in this context when QPSK symbols are used for bit-to-symbol mapping.