Research On Management Method Of Mmwave Array Antenna Under The Coverage Constraints Of Multi-dimension Network

The continuous demanding of high-speed transmission makes the spectrum bandwidth more and more scaricity.However,due to its limited bandwidth,the frequency band below 6GHz(Sub-6GHz)cannot meet the high bandwidth requirement.Therefore,more and more researchers are turning their attentions to the millimeter-wave(mm Wave)frequency band.Compared with the traditional Sub-6GHz low frequency band,the mm Wave band can better support high transmission rate requirements due to its extremely wide bandwidth.However,mm Wave transmission is seriously attenuated and easy to be blocked,which brings great challenges to the communication system design in the mm Wave band.In order to solve the problem of large signal attenuation in the mm Wave band,an array antenna needs to be introduced to compensate for path transmission loss through beamforming.However,after introducing array antenna,the antenna beam becomes narrow beam,and the array antenna management is required for the mm Wave network coverage performance optimization: First,from the link budget perspective,mm Wave beam management shall meet the link budget requirement to compensate for the severe signal attenuation;Second,even though the narrow beam can better support multi-user transmission,the main-lobe beam width should be controlled to avoid multi-beam interference;Finally,considering the narrow mm Wave beamwidth,when there is user mobility,it is easy for users to move out of the coverage of the main-lobe.Therefore,for the array antenna management,the user mobility support should be considered.Focusing on the above-mentioned mm Wave array antenna management requirements,in this thesis,we systematically study the mm Wave beam management regarding the Uniform Linear Array and Uniform Rectangle Array.We consider the link budget,user mobility,and interference control to improve the network coverage performance.The main contributions of this thesis are as follows:(1)Focusing on Uniform Linear Array(ULA),we quantify the main-lobe width,the main-lobe gain,and the null beam width with the number of array elements.Aiming at the problem of ULA sub-array allocation under multi-user conditions,to improve the network coverage performance regarding interference control,link budget,and beam coverage,we design an ULA array antenna management model.To solve the ULA array antenna management problem,we explore the integer relaxation and the geometric programming to derive a sub-optimal solution.Simulation results show that,our proposed ULA array antenna management method could statisfy the link budget and interference control problem,and in the meanwhile,can improve the user mobility support on static parameters by expanding the main-lobe beamwidth.(2)We further extend to the Uniform Rectangle Array(URA)array antenna management problem,which can better support beam management in the mm Wave band due to its smaller size.Specifically,focusing on URA,we quantify the main-lobe width,the main-lobe gain,and the main-lobe beam width with the number of array elements.Aiming at the problem of URA sub-array allocation under multi-user conditions,we design an URA array antenna management model to improve the network coverage performance regarding interference control,link budget,and beam coverage.To solve the URA array antenna management problem,we explore the integer relaxation,logorithm transform,successive convex approximation to conver the non-linear non-convex problem to a convex optimization problem,so as to derive a sub-optimal solution.Simulation results show that,our proposed URA array antenna management method could statisfy the link budget and interference control problem,and in the meanwhile,it can improve the user mobility support on static parameters by expanding the main-lobe beamwidth.