Joint Optimal Transceiver Design In Multi-hop MIMO System With Swipt

At present,the electronic devices used in the wireless communication network still mainly need to be charged by actual cable equipment.The insufficient battery storage capacity has become a bottleneck in the development of the wireless communication technology.Therefore,in this context,the simultaneous wireless information and power transfer technology attracts widespread attention.In the meantime,compared with the traditional one-hop transmission,multi-hop relay technology has the characteristics of reducing the transmission power of the system,extending the coverage of the communication network in the actual wireless communication process.Therefore,in this paper,the multi-hop relay technology and wireless portable technology will be combined and employed into the multi-input multi-output system to charge the user terminal,which is of great practical significance.Therefore,we in the optimization problem established in this paper.Based on the objective function of minimizing the mean square error or maximizing the maximum information rate,we study the optimal beamforming matrices of the source node and the relay nodes.In this paper,we propose a multi-hop network system with energy harvesting receiver based on wireless MIMO relay technology and multi?hop transmission technology.Subject to the constraints of limited transmit power at the source node and relay nodes and limited energy collection of the target node,the final optimization problems for minimizing the mean square error and maximizing the maximum information rate are established to be solved,setting beamforming matrices as optimization variables.For the established non-convex problems,we mainly apply two classical algorithms to solve non-convex problems:1.The channel parallelization algorithm.The channel parallelization algorithm transforms the original matrix problem into a scalar problem,then the original problem is convex.2.The successive convex approximation algorithm.The successive convex approximation algorithm transforms the original non-convex problem into convex one by approximately processing inequality constraints.To sufficiently study the multi-hop system,we also consider the two receiver mode:1)the time switching mode;2)the power splitting mode.We study the comparison of the two modes.The optimization problem based on multi-hop system has multiple variables and more constraint conditions,which brings difficulties to the variables decoupling,parameter setting and solving process.The simulation part mainly uses MATLAB and CVX convex optimization solver tool box to solve and get the final simulation curve of the mean square error,the bit error rate and information rate.The curves cover the trend of iteration and the trend of each parameter.The simulation shows that the convergence of the two algorithms comparison of the mean square error and the bit error rate performance and comparison of information rate performance of two receiver modes.The simulation fully proves the theoretical results:1)since the channel parallelization algorithm reduces the original matrix problem to a scalar problem,the algorithm has lower computational complexity and the simulation curve can converge fast.In contrast,the successive convex approximation algorithm sacrifices the complexity of the algorithm in return for better the mean square error and bit error rate performance;2)the power splitting mode receiver has better information rate performance than time switching mode receiver.