Research On Micro-Motion Parameter Estimation Based On Wideband Radar Phased Derived Range

Ballistic missile target identification as a key technology of missile defense system,has important military significance.Wideband radar has received extensive attention due to the high distance resolution.The high resolution range profile contains the micro-motion characteristics of the target,which is the important basis for the target recognition in the middle of the trajectory.Combining the wideband radar phase derived range technology and the micro-motion parameter estimation method,this dissertation mainly focuses on extraction of high resolution range profile,and estimation methods of the target's structure parameters and micro-motion parameters.The main work in this dissertation can be summarized as follows:1.Phase derived range technology based on wideband radar has been analyzed mainly.The condition of phase derived range is better than that of envelope delay and range performance is analyzed,and the relationship between the probability of phase cancellation and the relative bandwidth and signal-to-noise ratio is discussed.For the existence of multiple scattering centers,the method of IAA algorithm combined with Bayesian information criterion to complete the wideband echo phase ranging is proposed.Finally,the simulation results are used to verify the analysis results,which lay the foundation for the next step of micro-motion characteristic extraction.2.The method of estimating the micro-motion parameters of known shape targets based on phase derived range is studied.Based on the spatial scattering characteristics of the middle target of the trajectory,the shielding effect of the target is analyzed and verified by electromagnetic simulation experiment.Then the precession model is established,and the instantaneous velocity of the top scattering center and the equivalent scattering center of the flat cone,the cylinder cone and the skirt cone are analyzed from the mathematical point of view.However,the phase obtained by the phase ranging method in Chapter 2 includes not only the phase corresponding to the radial distance of the target but also the initial phase caused by the properties of the scattering center itself,resulting in the radial direction of the fretting target obtained by the phase ranging method Distance is biased.Since the initial phases at different moments are the same for the same scattering center.According to this feature,we get the difference between the distances to get the instantaneous speed,thus eliminating the scattering center itself caused by the bias.Then the method of estimating the angle between the radar sight and the moving axis and the target micro-motion parameters based on the phase velocity method is introduced.Finally,the parameters of three different shapes of flat cone,cylinder cone and skirt are realized by electromagnetic simulation experiment.3.The method of micro-motion parameter estimation for unknown shape targets based on phase derived range method is studied.In view of the fact that the shape of many space targets is smooth and is made up of multiple smooth surfaces,so the sliding scattering center will appear at the junction of the surface.It can be two-dimensional perspective of its various scattering centers in the radar line of sight projection sequence expression.Firstly,based on the phase distance method,the radial distance of the scattering center is obtained.The singular value decomposition is carried out to obtain the affine reconstruction of the radar angle matrix.Then,the affine result is reconstructed according to the geometric invariance.In order to solve the free rotation parameters,the arbitrary rotation matrix existing in motion reconstruction and the distance offset caused by the initial phase of the scattering center when using the phase ranging method,a triple iteration algorithm is proposed to collectively estimate these parameters.The advantage of this method is that as long as the projection sequence of the three non-collinear equivalent scattering centers on the radar's line of sight is obtained,the motion matrix of the target can be reconstructed to estimate the target's motion information.