Research On Electromagnetic Lens Array Assisted Angle Of Arrival Estimation And Implementation Of Algorithm Design

Millimeter wave(mm Wave)has become a pivotal area of research in modern wireless communication due to the advancement of communication technology.Millimeter wave penetration capability is relatively weak,and attenuation is severe during transmission.Large-scale multiple-input multiple-output(MIMO)techniques are often applied to millimeter wave systems to combat signal fading.The main contributions of this thesis are as follows.Firstly,the structural modeling and simulation of the two common lens antenna array structure are carried out to analyze the relationship between the AOA estimation results and parameters such as signal-to-noise ratio,number of antenna arrays,and lens design constants for two system structure models,and to analyze the performance in LOS and NLOS environments.The overall results show that the elliptical lens are better than EHS lens when using Root-MUSIC algorithm for AOA estimation,which is mainly due to the fact that the power distribution of elliptical lens is more uniform in the antenna subset than that of EHS lens,making the reception of each antenna element in the antenna subset more balanced.In addition,an algorithm for inversion estimation of the AOA,based on energy received by two common lens antenna arrays,has been proposed.Simulation results demonstrate that the algorithm’s performance in various SNR environments is superior to that of the Root-MUSIC algorithm.Meanwhile,for the problems that the EHS and elliptical lens structures are not easy to be integrated and the phase of the lens is neglected,a uniform linear array system based on Huygens super-surface is proposed and a theoretical system model is derived.Further,for the practical manufacturing requirements and high computational complexity,the mathematical expressions for the electric field and power of the plane lens with discrete unit cell phase shift profile are given.Finally,proposing the dataset and energy scan algorithms,a transformation of the AOA estimation problem from "spatial/angle domain" to "position domain" is proposed,thereby enhancing accuracy and decreasing computational complexity.Performance comparison and computational complexity analysis are also conducted.