Research On RCS Measurement Technology Based On 3D Super Resolution Imaging

Radar-Cross Section(RCS)can be used to characterize the scattering ability of the target,for target detection and recognition,and has important applications for the realization of stealth technology,so it is particularly important to improve the accuracy of RCS measurement.While traditional RCS measurement techniques need to be performed in a darkroom to avoid environmental interference,image-based RCS measurement technology separates the environment from the target and can be measured in the outer field.However,the discrete resolution introduced by imaging can reduce the accuracy of RCS measurements.Therefore,this paper introduces 3D super-resolution imaging technology into RCS measurement,uses near-field super-resolution imaging technology to obtain high-resolution images,and then extracts the scattering features of the target from the image,and then inverts to obtain the RCS measurement value of the target in the far field,so as to improve the imaging quality and RCS measurement accuracy.At the same time,this paper also explores a new RCS measurement system based on frequency diversity array and vortex wave,and integrates super-resolution technology.The main work and innovations of this paper are summarized as follows:1.The RCS measurement system and signal model based on virtual array are summarized,the traditional 3D imaging algorithm is introduced,the 3D imaging resolution based on the traditional virtual array is analyzed,and the definition of super-resolution is given.Then,the threshold method is used to extract the scattering center and the near-far field transformation algorithm.2.This paper studies the RCS measurement technology of three-dimensional superresolution imaging,and explains the principle of deconvolution based on the traditional linear array RCS measurement system.The target RCS under super-resolution imaging and the target RCS under traditional resolution imaging are compared with the target RCS under super-resolution imaging by using the compressed sensing algorithm to achieve superresolution,and the accuracy of the target RCS measurement based on the inversion of the super-resolution imaging results is higher,indicating that increasing the imaging resolution can effectively improve the inversion accuracy of the target RCS.3.This paper studies the target RCS measurement system based on Frequency Diversity Array(FDA).Firstly,the structure of the frequency diversity array is introduced,and its signal model is analyzed and the beam pattern is simulated.Then,the near-field measurement method based on frequency diversity array is used to image the target and invert to obtain the RCS measurement.It is found that the target RCS inversion value with high accuracy can be obtained by imaging the target by using the frequency diversity array,which can greatly reduce the complexity and cost of the array to a certain extent,and avoid the large bandwidth and nonlinearity problems of transmitting wideband signals.4.In this paper,the target RCS measurement system based on vortex electromagnetic wave frequency diversity circle array is studied.Firstly,the theoretical basis of vortex wave radar imaging is introduced,and then the principle of frequency diversity circular array to generate vortex electromagnetic waves is analyzed,and it is found that the mode of vortex waves changes with time and distance.Then,based on the circular array system,the target imaging results in the distance direction change periodically,and the imaging resolution in the azimuth direction can increase the resolution with the increase of the modal range,and finally the target RCS measurement technology based on frequency diversity circular array is prospected.