Massive MIMO

MIMO systems with large number of antennas, referred to as massive MIMO, are able to provide high antenna directivity and thus a high level of interference suppression. This chapter provides many ways to maximize the weighted sum rate in a linearly precoded multicellular downlink system where the receivers are equipped with a single antenna. antenna. It also considers the weighted sum rate maximization (WSRM) problem in the downlink of a multicellular setting with linear precoding by relaxing the stringent assumption of perfect channel state information (CSI) manly along the lines. The WSRM problem is a challenging nonconvex problem. In fact, recently it has been shown to be strongly NP‐hard even in the case of perfect CSI availability. Hence, we need to find the approximate solution of the problem. Finally the chapter presents a short procedure that outlines steps needed to solve the robust WSRM problem.