A low-complexity vector precoding scheme for large multiuser MIMO systems

In this paper, the precoding problem for large multiuser multiple-input multiple-output (MU-MIMO) systems has been considered since precoding for such large systems has been a challenge on account of prohibitive complexity. Hence, we propose a well-performed low-complexity vector precoding scheme, which is termed as the oriented reactive tabu search (ORTS). Its low complexity is achieved by searching the perturbation vectors along a certain direction instead of all the possible candidates in the solution space. In addition, thanks to its ability of the ORTS scheme to escape from poor local minima, the improved performance is obtained as well. Furthermore, it is observed that the bit error rate (BER) performance increases with the number of simultaneously served user terminals in a near-exponential manner. Thus the proposed scheme is proper for the large systems in terms of complexity as well as performance. Numerical simulations verify the improved performance and the reduced complexity.