Research On Distributed Beamforming And Energy Efficiency Optimization

With the rapid increasement of wireless smart devices and various mobile applications,a higher requirement of capacity and energy efficiency of wireless communication network is proposed.Thus promotes the development of wireless communication networks from the traditional single homogeneous structure to the direction of large-scale,multi-layered,heterogeneous.Spectral efficiency and energy efficiency is one of the key issues in the development of the network.Our research work is concentrated on the maximization of spectral efficiency and energy efficiency respectively.A distributed beamforming algorithm based on monotonic optimization for multicell multiuser downlink system of resource allocation and power control is proposed.Firstly,the optimization problem is formulated as the maximization of the weighted sum rate subject to the power constraint of single base.Sceondly,the algorithm simplifies the objective function with the decouping characteristics and then decomposes the WSR maximization problem into parallel single-cell sub problems which involve only local channel state information.Finally,the main idea is to rewrite the objective function as a standard monotonic programming.Outer polyblock approximation algorithm is devised to search for the optimal solution.Numerical simulation shows that the proposed algorithm has better convergence behavior and each base station utilizes only the local CSI to compute its beamforming vectors.A distributed outer polyblock approximation algorithm is proposed for energy efficient maximization in multiuser massive MIMO system.The energy efficient optimization problem is considered as the maximization of the ratio between the system sum rate and the system power consumption.Firstly,The fractional programming optimization target was transformed into a subtractive form via using the fractional programming theorem.Secondly,the problem is formulated as a monotonic programming.Finally,a distributed approach to figure out the projection of a vertex onto the feasible power region was proposed by jointly exploiting the both virtues of monotonic optimization and nonlinear Perron-Frobenius theory.Numerical simulation shows that the proposed projection algorithm exhibits geometrical convergence and lessen the overall computation cost and realizes the global optimum for energy efficient problem.