Performance evaluation of massive MIMO for 5G wireless systems

The last years have seen a massive growth in the number of connected wireless devices. Billions of devices are connected and managed by wireless networks. At the same time, each device needs a high throughput to support applications such as voice, real-time video, movies, and games. Demands for wireless throughput and the number of wireless devices will always increase. In addition, there is a growing concern about energy consumption of wireless communication systems. Thus, future wireless systems have to satisfy three main requirements: (i) having a high throughput; (II) simultaneously serving many users; and III) having less energy consumption. Massive multiple-input multiple-output (MIMO) technology, where a base station (BS) equipped with very large number of antennas (collocated or distributed) serves many users in the same time-frequency resource, can meet the above requirements, and hence, it is a promising candidate technology for next generations of wireless systems. A huge throughput and energy efficiency can be achieved owing to the multiplexing gain and the array gain. It can utilize one power hungry radio frequency (RF) with each antenna. Owing to high power consumption of RF chain components, the practical implementation of massive MIMO is considered a challenging problem. This thesis presents high power consumption problem from two different aspects. The first aspect depends on reducing the number of RF chains and divides into two parts. The first part, hybrid pre coding consists of mixed of analog and digital processing which is based on minimum mean square error (MMSE) algorithm. Extensive simulation programs are executed to compare the performance of the proposed MMSE based hybrid pre coding scheme with analog beam forming performance, block diagonalization (BD) based hybrid pre coding and zero forcing (ZF) based hybrid pre coding. Moreover, studies on the impact of modified MMSE based hybrid beam forming parameters on the system performance are done. These parameters such as; the number of BS antennas, the number of mobile station antennas, number of effective channel quantization bits and number of RF beam forming quantization bits. Besides, the impact of rate threshold on the coverage probability is studied under different values of N_BS antennas