Multi-Cell Massive MIMO: Power Control and Channel Estimation

Abstract

Cellular network operators have witnessed signi cant growth in data tra c in the past few decades. This growth occurs due to the increase in the number of connected mobile devices, and further, the emerging mobile applications developed for rendering video-based on-demand services. As the available frequency bandwidth for cellular communication is limited, signi cant e orts are dedicated to improving the utilization of available spectrum and increasing the system performance with the aid of new technologies. Third-generation (3G) and fourth-generation (4G) mobile communication networks were designed to facilitate high data tra c in cellular networks in past decades. Nevertheless, there is still a requirement for new cellular network technologies to accommodate the ever-growing data tra c demand. The fth-generation (5G) is the latest generation of mobile communication systems deployed and implemented around the world. Its objective is to meet the tremendous ongoing increase in the data tra c requirements in cellular networks.Massive MIMO (multiple-input-multi-output) is one of the backbone technologies in 5G networks. Massive MIMO originated from the concept of multi-user MIMO. It consists of base stations (BSs) implemented with a large number of antennas to increase the signal strengths via adaptive beamforming and concurrently serving many users on the same time-frequency blocks. With Massive MIMO technology, there is a notable enhancement of both sum spectral e ciency (SE) and energy e ciency (EE) in comparison with conventional MIMO-based cellular networks. Resource allocation is an imperative factor to exploit the speci ed gains of Massive MIMO. It corresponds to e ciently allocating resources in the time, frequency, space, and power domains for cellular communication. Power control is one of the resource allocation methods of Massive MIMO networks to deliver high spectral and energy e ciency. Power control refers to a scheme that allocates transmit powers to the data transmitters such that the system maximizes some desirable performance metric.The rst part of this thesis investigates reusing a Massive MIMO network's resources for direct communication of some speci c user pairs known as deviceto-device (D2D) underlay communication. D2D underlay can conceivably increase List of Abbreviationsxi