Joint Design of Frequency Domain Pre-equalization and Beamforming for Single Carrier Massive MIMO System

In this paper, we investigate the performance of single-carrier frequency domain processing as the downlink transmission scheme in a broadband multi-user and massive multiple input multiple output system. Firstly, the pre-coding forms in multi-user massive MIMO downlink are derived, and both matched filtering (MF) and zero forcing (ZF) precoding schemes are included. Then, the theoretical derivations and simulations of sum-rate in both OFDM and SC-FDP systems are given and show that SC-FDP has similar performance in sum-rate compared with OFDM in large-scale MIMO system. After that, the peak-to-average ratio (PAPR) between OFDM and SC-FDP are analyzed, and show that SC-FDP has a smaller PAPR than OFDM when the number of users is small, and as the number of users increasing the gap decreases. Finally, we analyze the computational complexity of OFDM and SC-FDP, the overall computational complexity of the two system is comparable except that the main computational task of SC-FDP is completed at the base station. Due to the mentioned facts, SC-FDP can be considered as a very promising transmission scheme in multi-user massive MIMO downlink.