Research Of Three Dimensional Beamforming And Power Allocation

MIMO (Multi-Input Multi-Output) technology, as a key technology of LTE and TD-LTE system, can significantly improve system capacity and coverage. Because of the existing passive antenna structure, MIMO is difficult to use the degree of freedom of the channel and control the spatial distribution of the signal in the vertical dimension. To solve the problem, three dimension multi antenna based on AAS (Active Antenna Systems) technology emerged. Low-noise amplifier, power amplifier, filter and passive cooling device can be integrated in each of the radiating elements of the antenna array. Each element of antenna array can be independently controlled via a digital interface, so network deployment is more flexible and the system capacity and coverage can be improved. Channel is extended from two dimension to three dimension. Compared to traditional linear array antenna, three dimensional multi antenna can take advantage of the vertical freedom of3D channels.3D MIMO can improve the overall efficiency and performance of wireless communication system, and enhance the quality of service at the same time. This paper mainly studies the three-dimensional beamforming algorithm and power allocation algorithms, and evaluates the performance gain of algorithm.Firstly, we propose the innovative three-dimensional beamforming algorithms. The theory of simple3D beamforming algorithm and accurate3D beamforming algorithm is introduced. After analyzing the shortcomings of existing algorithms, two improved algorithms is proposed. The core idea is grouping the antenna array in horizontal dimension and vertical dimension respectively. The proposed algorithms can reduce complexity of calculating weight matrix and ensure the performance of the system. Then the simulation is implemented and the advantages of the improved algorithms are analyzed.In the second part, we design the three-dimensional power allocation algorithm. With the consideration of the vertical dimension channel information and characteristic spatial distribution of three-dimensional antenna array, three-dimensional power allocation algorithm is proposed, which is based on water power allocation algorithm. Then the simulation is implemented. The results show that the proposed three-dimensional power allocation algorithm can improve the overall system capacityFinally, conclusions are made and future research plans are discussed.