Robust Optimizaiton Algorithm Design For SWIPT Based MIMO Systems

With the rapid development of new technologies such as MIMO,smart antenna, software defined radio and new business such as mobile in wireless communications, the integration of wireless communication systems and Internet of Things further deepen. RFID, wireless sensor networks and other key technologies in the Internet of Things require communication nodes which are low-power and can long time run without direct energy supply. In this case, the energy supply has become a bottleneck in wireless communication technology and Internet of Things in some applications deployment. Therefore, the concept of Simultaneous Wireless Information and Power Transfer is proposed and has become a popular research technique with broad research potential and application prospect in recent years.In the practical application, the channel state information obtained by the transmitters in MIMO systems is often in error with the real channel state information due to the fast changing channel and the limited bandwidth feedback channel. It is possible that the energy harvested by user nodes is insufficient to maintain the node operation due to the channel estimation error, which may be catastrophic.In this paper, we focus on three types of SWIPT-based MIMO system models and their corresponding robust transmission optimization algorithms to reduce the impact of channel estimation error on the wireless energy-carrying system in practical application scenarios. Based on the different channel estimation error description methods, we establish the constraint conditions and the objective function. Convex optimization algorithm is used to convert the original optimization problem to solvable convex problem and we finally obtain the solution of the problem. We also build a link-level simulation platform for the algorithms proposed in this paper, including:A robust design scheme for MISO system downlink transmitter with both non-charging user nodes and charging nodes is proposed. It is emphatically studied that under the condition that only the channel error boundary is given, with power limit and SINR constraints of each link,the base station transmitter optimization algorithm that maximizes the minimum receiving energy of the charging node and guarantees the communication quality while maintaining the long-term operation of the node without direct energy supply.A robust design scheme for MISO system downlink transmitter with multiple energy-charging nodes is proposed. It is emphatically studied that under the condition that only the channel error boundary is given,considering the same-channel interference between nodes, the base-station transmitter optimization algorithm of maximizing the weighted average minimum received energy of the charging nodes. The algorithm can effectively resist the channel estimation error and interference between user and guarantees the information transmission while maintaining the energy supply.A robust transceiver design scheme based on SWIPT for full-duplex bi-directional link MIMO systems is proposed. Under the transmitter energy limitation and co-channel self-interference, the algorithm can maintain energy consumption of the user node while minimizing the total mean square error of uplink and downlink. The balance between communication quality and energy supply is achieved.Simulation results show that the robustness optimization algorithms proposed in this paper is validated in different scenarios. The algorithms can effectively resist the influence of channel estimation error and improve the system performance while maintaining the low complexity.The simulation results of algorithms are analyzed, and the key factors affecting the system performance under different scenarios are given.