Beamforming for multiple users in line of sight environments

Due to the increasing number of communication devices used today and the increase in the required data size and data transfer rate for each device, the existing communication infrastructures are inadequate and therefore multi-input multi-output systems are needed. The massive multi-input multi-output systems are large-scale phase array antenna structures consisting of a plurality of antenna elements that allow simultaneous communication with multiple users. It is envisaged to use millimeter wavelength during communication in massive multi-input multi-output systems. In this thesis, various properties of millimeter wavelength were investigated. First of all, it is necessary to use high broadcast frequency in order to communicate width high bandwidth. Secondly, since the communication is made using high frequency broadcast, the size of the antennas to be used during communication will be reduced. This will increase the number of antennas in the same unit area. With the increase in the number of antennas, the narrow beamwidth used in communication. Because of the decrease in reflection and diffusion losses, instead of the beamforming structure that can be used under multipath conditions, beamsteering methods need to be used and accordingly, they are suitable to be used in line of sight environments. Within the scope of this thesis, the basic features that constitute the infrastructure of the massive multi-input multi-output systems and the performance of the communication which can be done in line with the line of sight in multi-user environments are examined. Different antenna pattern designs were also used during the analyzes. Three different beam orientation techniques were compared within the scope of the mentioned investigations.