The capturability of an arbitrarily maneuvering target featuring speed superiority over an interceptor is analyzed for Augmented Pure Proportional Navigation(APPN)and RetroAugmented Proportional Navigation(RAPN)guidan...The capturability of an arbitrarily maneuvering target featuring speed superiority over an interceptor is analyzed for Augmented Pure Proportional Navigation(APPN)and RetroAugmented Proportional Navigation(RAPN)guidance.This paper focuses on intercepting arbitrary maneuvers to study more general interception problems.A comparative analysis of the capture region between head-on interception related to APPN and head-pursuit interception related to RAPN is proposed.The results indicate that RAPN performs better than APPN in capturability.It is concluded that increasing the target velocity,which increases the velocity ratio,significantly weakens the capturability of the interceptor,and the average acceleration and relative distance affect the location of the capture region but not its size.The analysis is based on prior knowledge of the target maneuver,which inevitably leads to deviations from actual maneuvers in practical engagement,so a deviation analysis is implemented.The effective capture region shrinks as the absolute value of acceleration deviation increases,and the RAPN has a better deviation fault tolerance compared with the APPN.The results reveal that a larger relative distance can weaken the deviation fault tolerance,and the target velocity has opposite effects on head-on and head-pursuit interception.展开更多
A space-based bistatic radar system composed of two space-based radars as the transmitter and the receiver respectively has a wider surveillance region and a better early warning capability for high-speed targets,and ...A space-based bistatic radar system composed of two space-based radars as the transmitter and the receiver respectively has a wider surveillance region and a better early warning capability for high-speed targets,and it can detect focused space targets more flexibly than the monostatic radar system or the ground-based radar system.However,the target echo signal is more difficult to process due to the high-speed motion of both space-based radars and space targets.To be specific,it will encounter the problems of Range Cell Migration(RCM)and Doppler Frequency Migration(DFM),which degrade the long-time coherent integration performance for target detection and localization inevitably.To solve this problem,a novel target detection method based on an improved Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm is proposed in this paper.First,the echo model for bistatic space-based radar is constructed and the conditions for RCM and DFM are analyzed.Then,the proposed GS-orthogonalization OMP method is applied to estimate the equivalent motion parameters of space targets.Thereafter,the RCM and DFM are corrected by the compensation function correlated with the estimated motion parameters.Finally,coherent integration can be achieved by performing the Fast Fourier Transform(FFT)operation along the slow time direction on compensated echo signal.Numerical simulations and real raw data results validate that the proposed GS-orthogonalization OMP algorithm achieves better motion parameter estimation performance and higher detection probability for space targets detection.展开更多
基金the National Natural Science Foundation of China(No.62073335)the Science Fund for Distinguished Young People in Shaanxi Province,China(No.2022JC-42)the China Postdoctoral Science Foundation(Nos.2017M613201,2019T120944 and 2020M683737).
文摘The capturability of an arbitrarily maneuvering target featuring speed superiority over an interceptor is analyzed for Augmented Pure Proportional Navigation(APPN)and RetroAugmented Proportional Navigation(RAPN)guidance.This paper focuses on intercepting arbitrary maneuvers to study more general interception problems.A comparative analysis of the capture region between head-on interception related to APPN and head-pursuit interception related to RAPN is proposed.The results indicate that RAPN performs better than APPN in capturability.It is concluded that increasing the target velocity,which increases the velocity ratio,significantly weakens the capturability of the interceptor,and the average acceleration and relative distance affect the location of the capture region but not its size.The analysis is based on prior knowledge of the target maneuver,which inevitably leads to deviations from actual maneuvers in practical engagement,so a deviation analysis is implemented.The effective capture region shrinks as the absolute value of acceleration deviation increases,and the RAPN has a better deviation fault tolerance compared with the APPN.The results reveal that a larger relative distance can weaken the deviation fault tolerance,and the target velocity has opposite effects on head-on and head-pursuit interception.
文摘A space-based bistatic radar system composed of two space-based radars as the transmitter and the receiver respectively has a wider surveillance region and a better early warning capability for high-speed targets,and it can detect focused space targets more flexibly than the monostatic radar system or the ground-based radar system.However,the target echo signal is more difficult to process due to the high-speed motion of both space-based radars and space targets.To be specific,it will encounter the problems of Range Cell Migration(RCM)and Doppler Frequency Migration(DFM),which degrade the long-time coherent integration performance for target detection and localization inevitably.To solve this problem,a novel target detection method based on an improved Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm is proposed in this paper.First,the echo model for bistatic space-based radar is constructed and the conditions for RCM and DFM are analyzed.Then,the proposed GS-orthogonalization OMP method is applied to estimate the equivalent motion parameters of space targets.Thereafter,the RCM and DFM are corrected by the compensation function correlated with the estimated motion parameters.Finally,coherent integration can be achieved by performing the Fast Fourier Transform(FFT)operation along the slow time direction on compensated echo signal.Numerical simulations and real raw data results validate that the proposed GS-orthogonalization OMP algorithm achieves better motion parameter estimation performance and higher detection probability for space targets detection.