Research On Power Optimization Of Enhanced Multi-beam Antenna System In Communication Satellite

With the rapid growth of network capacity and the number of users in modern satellite communication systems,multi-beam antennas have emerged and have been widely used.The multi-beam reflector antenna has the advantages of narrow main lobe,high gain,simple structure,and excellent performance.It can realize frequency reuse through spatial isolation and improve the communication capacity and spectrum utilization rate of the satellite communication system.The multi-beam antenna system using the enhanced beamforming method and the multi-port amplifier can effectively improve the utilization rate of the power amplifier and reduce the influence of a single power amplifier on the beam.This thesis focuses on the research of enhanced multi-beam reflector antenna beamforming optimization and antenna system power optimization design,specifically starting from the following three aspects: 1.First,the basic principles of the multi-beam antenna system are studied.The basic parameters that affect the performance of the antenna are introduced,the working principles and implementation methods of the beamforming matrix,the multi-beam reflector antenna and the multi-port amplifier are mainly explained,and the spatial multiple beam frequency multiplexing scheme and co-frequency interference are studied and analyzed.2.Optimize the design of the space beamforming of the enhanced multi-beam reflector antenna.The principle of stimulation optimization of the feeder array is elaborated in detail.Given the expected pattern,two schemes of function fitting and envelope sampling are designed to construct the beamforming optimization objective function.By introducing the elitist strategy and pseudo-parallel genetic strategy to improve the genetic algorithm,a feeder stimulation coefficient optimization algorithm based on improved genetic algorithm(IGA)is proposed to carry out different models constructed optimize solution.The results show that the 64 beams optimized by the two models meet the system requirements,the main lobe gain is greater than 49.65 d Bi,and the carrier-to-interference ratio is greater than 12 d B;In terms of circumstances,the effect of the envelope sampling method is better than the function fitting method.3.Optimize the design of the multi-port amplifier output power of the enhanced multi-beam antenna system.The principle of the multi-beam antenna system based on the multi-port amplifier was studied in detail,and an enhanced multi-beam satellite antenna stimulation mapping model based on the Divided Architecture Based on Multi-port Amplifier(DA-MPA)was designed.By introducing a hybird evolutionary algorithm and an adaptive parameter control strategy to improve the differential evolution algorithm,a multi-beam satellite antenna stimulation mapping algorithm based on the improved differential evolution algorithm(IDE)is proposed,aiming at the multi-beam antenna system in different simulation scenarios Optimize the design of the stimulation mapping relationship.The results show that the stimulation using mapping optimization algorithm based IDE multibeam satellite antenna mapping relationship between the target stimulation,can effectively suppress the influence of the mixing matrix for coherent input signals.Compared to conventional non-stimulation mapping mode,the proposed algorithm can improve the power efficiency of antenna system by 46.89%.