Research On Polarization Control And Synthesis Method Of Full Polarization Conformal Phased Array

Conformal antenna can expand the spatial coverage of radar and conform to the surface of its carrier,thereby reduce the impact on aerodynamic performance.Therefore,conformal antenna has unique advantages and broad application prospects in the field of electronic warfare,missile defense and meteorological monitoring.With capabilities of polarization diversity and accurate polarization measurement,phased array radar system can be able to receive and make full use of polarization scattering signal.Based on these technique,Full Polarization Conformal Phased Array(FPCPA)can improve the performance of modern radar.Firstly,the study background and research status of FPCPA is introduced in detail.Basic concepts and pattern theories of array antenna are combined to establish the mathematical pattern model of FPCPA,which can be used to conduct experiments on polarization control and pattern synthesis.In addition,the mutual coupling matrix(MCM)is extracted and can be applied to calibrate the array's excitations.Based on the analysis of polarization pattern model,the idea of multi-objective optimization is used in pattern synthesis.And with the concept of convex optimization algorithm,a multi-objective pattern synthesis method is presented.By taking different optimization targets of pattern synthesis into consideration,the classification of convex optimization problems is completed.Then solving tools and steps of convex optimization method in pattern synthesis of antenna are also given.The mathematical model of FPCPA and multi-objective optimization algorithm are the basis to establish electromagnetic simulation model of FPCPA.A dual-layer microstrip antenna with differential feed is designed to achieve high isolation and high polarization purity.At the same time,a compact improvement is made to make it more suitable for the configuration design of conformal array.Design and simulation of full polarization cylindrical conformal subarray are conducted to build the cylindrical array which is developed from the sub array.Then using the embedded pattern instead of isolated pattern to do low sidelobe scanning pattern experiments,which makes array analysis and synthesis more precise since effects of the mutual coupling are considered.Then this essay designs and simulates a spherical FPCPA and a Geodesic Dome Phased Array Antenna(GDPAA),and completes these array's active area calculation as basis of pattern synthesis.For the GDPAA,after the calculation of active area,its surface is divided by the calculation results and then grouped into typical sub array that consists of several facets,thereby the efficiency of pattern synthesis can be improved.