Study On Joint Parameter Estimation Method Of Polarization And Spatial For Conformal Polarization Array

Conformal polarization sensitive array refers to the antenna array where the antenna element is installed on the surface of the carrier and fits the outer shape of the carrier.Compared with scalar arrays,the conformal polarization sensitive array can reduce the flight resistance of the carrier,improve the stealth ability,and distinguish With higher capabilities,conformal polarization sensitive arrays are widely used in many fields such as radar and sonar.Conformal polarization sensitive array can sense the target's angle domain,polarization domain and other multi-dimensional information at the same time,but its geometric structure is more complicated,the array airspace steering vector no longer has a Toeplitz structure,and the antenna pattern of each element is also different,Which brings great difficulty to the design of parameter estimation algorithm.This paper analyzes the influence of the conformal structure of the array on parameter estimation,and studies the polarization-space multi-parameter joint estimation algorithm based on the conformal polarization-sensitive array.The main contents are as follows:1.Introduce the basic theory of polarization,use Euler rotation transformation to calculate the pattern of the conformal polarization sensitive array,and establish the received data model of the conformal polarization sensitive array.2.Aiming at the problem that the conformal polarization sensitive array is affected by the curvature of the carrier,the orientation of the array element at different positions is different,and the metal carrier has a "blocking" effect,and the MUSIC algorithm cannot be directly applied.Firstly,the sub-array segmentation technology is introduced.Using the sub-array segmentation technology to divide the conformal array into multiple sub-arrays can effectively overcome the performance degradation of the MUSIC algorithm caused by carrier occlusion,but the sub-array segmentation must consider the specific array structure.On this basis,in order to realize parameter estimation under any array structure,this paper combines manifold separation technology and virtual transformation technology to study the parameter estimation method of conformal polarization sensitive array.Manifold separation technology rewrites the array manifold In the form of the product of the sampling matrix and a Vandermonde structure vector,the MUSIC algorithm can be extended to any array;while the virtual transformation technology transforms the original array receiving data into the expected virtual array receiving data,because the virtual array is the desired ideal array Therefore,classical parameter estimation algorithms can be used.The simulation results show that these two methods can effectively estimate the DOA and polarization parameters of the signal.3.In view of the various array manifold errors in the actual environment,a conformal polarization-sensitive array error receiving data model is established,and the influence of errors on parameter estimation is analyzed.The existence of the array error makes the performance of the existing algorithm degrade or even invalid.Therefore,this article considers first using the Capon spectrum to estimate the approximate interval of the signal,and then constructs a projection matrix to project the received data to the signal interval.After the projection transformation,the error term of the signal vector will fall on the projection In the matrix,the signal vector is closer to the real steering vector,and a robust polarization-DOA estimation method based on projection transformation is established.Therefore,the use of projection transformation can suppress the influence of errors and improve the robustness of the algorithm.Simulation experiments and measured data The processing results show that this method can effectively estimate the signal parameters in the presence of array errors.