Research On The Model Of Dual-polarized Multi-beam MIMO Communication System

Multiple Input Multiple Output(MIMO)technology combined with satellite communications can make full use of space diversity or polarization diversity,increase gain without adding additional power and bandwidth,and use polarization diversity to form a polarized satellite MIMO The system is one of the ways that MIMO technology is applied to satellite communication.However,when using polarization diversity to construct a MIMO communication system,the existing research work focuses on describing the advantages of MIMO technology applied to satellite communication,designing various polarized antennas,and regarding the Cross Polar Discrimination(XPD)in There is less impact analysis in the communication environment.At the same time,when building a geostationary satellite(GEO)dual-polarization multi-beam satellite communication system channel model,the existing research only considers the scattering in the small-scale fading part of the transmitted signal,but it is tracking small objects,especially animals.At this time,the propagation phenomenon of ground reflection appears to be particularly important.However,there are still few studies on ground reflection modeling in the UHF(Ultra High Frequency,UHF,300 MHz-3000MHz)frequency band,and existing models of ground reflection are also not suitable for satellite communication scenarios.The main work of this paper is to first propose a method to analyze the impact of XPD on the system for the GEO single-satellite dual-polarization MIMO communication system model,and derive the Signal-to-Interference and Noise Ratio(SINR)in detail.Using MATLAB platform to evaluate the error performance and channel capacity of three propagation environments in open areas,suburbs,and urban areas under cross-polarized interference.However,the mathematical statistical model considers fewer influencing factors,and a single dual-polarized antenna can only construct a 2×2 MIMO system,and the diversity gain obtained is very limited.But the multi-beam antenna can form multiple point beams in the system to realize frequency multiplexing between beams and improve the spectrum utilization of the communication system.Therefore,this article is based on the UHF frequency band,and combines the omni-directional dual-polarized antenna with The combination of multi-beam array antennas makes it applicable to GEO satellites,and considers other influencing factors in the actual satellite-to-earth link transmission signal process: spatial and polarization correlation,direct line-of-Sight(LOS)signal Shadow fading,multipath effects,environmental cross-polarization coupling(Cross Polar Coupling,XPC),etc.,are modeled in MATLAB for the GEO dual-polarization multi-beam satellite communication system.At the same time,considering that the receiving end is a small object,especially in the case of wild animals,the impact of ground reflection signals and Doppler frequency shift on the communication system.