Study And Application Of Beam Characteristics Of Frequency Diversity Array

Frequency diverse array(FDA)is a new type of array that is different from traditional phased array.FDA can generate spatial scanning beam by introducing a linear frequency increment far less than the carrier frequency on the excitation RF signals of each element.FDA reduce the cost of beam-scanning antenna by avoid using the expensive phase shifters in the traditional phased array.In addition,the FDA has many characteristics different from traditional array which makes FDA have a good application prospect in the fields of radar detection and communication.Based on this background,the thesis conducts the design and research of FDA.The work done is as follows:1.Investigated the development focus and research hotspots of FDA technology at home and abroad,and comprehensively introduced and summarized the development path,basic working mechanism and latest progress of FDA.2.The radiation mechanism of the frequency diversity linear array is analyzed systematically.By analyzing the time factor,space factor and frequency step included in the synthesized phase factor obtained by the array superposition theorem,the characteristics of the beam peak changes with time,space and angle are revealed.The theoretical results are verified by simulating a frequency diversity linear array antenna.3.The radiation mechanism of the frequency diversity circular array is studied.Taking the far-field radiation field formed by the circular array superposition theorem as the research object,the mechanism and characteristics of generating space-time transformed vortex electromagnetic waves are revealed and a frequency diversity circular array antenna is designed and simulated to verify the theoretical results.The basic methods and simulation results of modal discrimination are also studied.4.The ability of the traditional arrival wave estimation algorithm to determine the irradiation direction of the FDA is analyzed,and the application in radar detection compared with the traditional phased array is studied.5.The scattering characteristics of a typical target scatterer illuminated by a frequencydiversity linear array in the time and frequency domains are studied,including the surface current distribution and the spatial scattering field distribution of the scatterer.The potential advantages of scattering characteristics of the scatterer in radar detection compared with the traditional phased array are analyzed.The frequency diversity linear array and frequency diversity circular array proposed in this paper have great engineering application value in the field of radar detection and communication.