Research On Clutter Processing Methods Of Conformal Array Airborne Radar

Conformal array airborne radar has become an important branch with its advantages of flexible array element distribution,good stealth performance and wide detection range.However,it also faces the problems of complex clutter characteristics.In this thesis,the clutter processing of the conformal array airborne radar is studied.The clutter model and the signal model of some typical conformal arrays are studied,and the clutter characteristics are analyzed.The space-time adaptive processing(Space-Time Adaptive Processing,STAP)method is used to deal with the clutter,including the non-side-looking linear array and circular array in the form of plane array,the cylinder array and irregular array in the form of three dimensional array,and the space-time adaptive processing in the transmitting end.The main research contents are divided into the following four parts.1.Signal modeling and characteristic analysis of planar conformal array airborne radar.For two kinds of planar conformal arrays,i.e.squinted(non-side-looking)array and circular array,we establish the array model and clutter echo model,and analyze the non-stationary characteristics of clutter.2.Research on STAP clutter processing method of conformal array airborne radar.The basic principle and processing idea of space-time processing method are introduced.The Doppler Compensation method is applied to the array bias case under the conformal array model,and the compensation method is applied to the difference of clutter distribution caused by the spatial steering vector of the conformal array,which can improve the clutter processing performance under different array placement cases.The near and long-distance clutter processing effect of non-side-looking linear array and circular array is simulated.3.Research on signal modeling and clutter processing of three-dimensional conformal array airborne radar.The cylindrical array and irregular array are introduced.The directional array elements are used to synthesize the pattern of the array,and the signal model is established.The clutter STAP processing method under the threedimensional conformal array and the compensation processing under the non-side-view condition are simulated by comparing the clutter eigen-spectrum and power spectrum with the planar array.4.Research on STAP method of adding transmitter information.The airborne radar signal modeling method with transmitter information is introduced,the STAP method using spatial domain and time domain two-dimensional information processing is simulated and compared with several typical dimension-reduced STAP methods.In a word,starting from the array form,the array and signal model are established from planar linear array,ring array to three-dimensional array,and the differences between the array and the conventional linear array are analyzed.By using the idea of reducing the differences,clutter processing methods under different array placement conditions are given.