Signal processing for massive MIMO communications

Massive multiinput multioutput (MIMO), a.k.a. large-scale antenna systems, is being considered as one of the key enabling technologies for the fifth generation and beyond fifth generation wireless networks. During the last few years, massive MIMO technology has appeared as the game changer in terms of spectral efficiency as well as energy efficiency to accommodate a large number of users at extraordinarily high data rates while consuming much less power. The aim of this chapter is to provide an overview of and address various important signal processing aspects of massive MIMO systems. We first discuss the information-theoretic pathway toward the development of massive MIMO systems, then briefly introduce standard precoding and decoding techniques, identify the key signal processing challenges, such as channel estimation and pilot contamination, along with possible solutions, and finally highlight some future research directions.