Research On Nonuniformity Design Of UWB Array Antenna

In recent years,the radar technology has developed rapidly,so it poses new challenges to radar electronic war which detect and interfere with radar.On one hand,the new radar types and models are emerging in an endless stream,so that the radar battlefield environment has become very complex;the other hand,modern radars which equipped with advanced system have a superior anti-reconnaissance and anti-jamming capability.so,we must explore new technical means to improve the ability of radar electronic warfare in reconnaissance and interference.Digital systems have high reliability,good stability and high reusability of good features,so more and more people began to pay attention to it.The use of digital systems instead of analog systems in various fields of electronic engineering has become an inevitable trend.Digital beamforming(DBF)is the core of digital array antenna technology.Narrowband DBF technology has a more mature application in radio systems,but DBF in broadband still has great difficulty.The traditional uniform array antenna has a good performance in the narrow band,but it's performance has declined in the broadband due to the aperture effect and grille and other problems.So,the non-uniform antenna arrays are posted.Some good non-uniform antenna array can use less antenna to obtain a larger antenna aperture which can greatly improve the DOA resolution,so the non-uniform antenna array have a better performance in broadband applications.However,the unreasonable arrangement of non-uniform antenna will to some issues,so how to design a reasonable arrangement of non-uniform antenna array has become a hot research problem.In this paper,the signal model of uniform and non-uniform antenna array and the indexes of antenna pattern are given,then we figure out some problem of uniform antenna array model in broadband application.Next,some kinds of one-dimensional non-uniform antenna arrays are studied and a new one-dimensional non-uniform array is proposed to extend the bandwidth(instantaneous bandwidth and operating bandwidth).The beam pattern in three octaves is given by MATLAB simulation.We examine the maximum sidelobe level,the average sidelobe level,3d B bandwidth and some other indicators to study its changes in the law.Then we study the direction diagram of different beam pointing,and verify its beam pointing accuracy index.Then,we compare five different kinds of nonuniform antenna arrays to summarize their application scenarios.Finally,we improve the performance of the antenna pattern by selecting a reasonable window function.In the actual process of digital beamforming,the actual formation of the beam is different from the expected value due to the various non-ideal factors,so the need for its analysis so the analysis is needed.In this paper,the influence of amplitude and phase error on the performance of digital beamforming is investigated.The simulation results show that when there is amplitude error,the maximum value of the beam pattern will be offset,the size of the sidelobe level of the beam will also change.