Aim To propose a generalized and closed representation of the Wigner Ville Hough transform(WVHT), for the moving target detection and imaging in the design of synthetic aperture radar(SAR). Methods Based on the li...Aim To propose a generalized and closed representation of the Wigner Ville Hough transform(WVHT), for the moving target detection and imaging in the design of synthetic aperture radar(SAR). Methods Based on the line integral, the WVH transform was derived by combining the Wigner Ville distribution (WVD) and the Hough transform (HT) together. The new transform was then verified with computer by the simulated SAR echoes. Results and Conclusion The correctness and the validity of the WVH transform were proved by the computer simulation. Compared with the conventional WVD HT method, the new approach based on the WVHT can simplify the processing procedure, it can translate the chirp echoes of multi targets of SAR from the time domain into the parameter space directly, while suppressing the cross terms of WVD and estimating the motion coefficients for the final imaging. It is obvious that the WVH transform can be also used in other cases for the chirp signal detection.展开更多
As the core of a digital phased array radar system,a radar signal processing environment is created to measure multitarget range and velocity information. The radar echo signal is achieved by superposing target echo, ...As the core of a digital phased array radar system,a radar signal processing environment is created to measure multitarget range and velocity information. The radar echo signal is achieved by superposing target echo, noise, clutter and jamming signals linearly. Considering that these signals have many types,two typical combinations are selected to construct the multi-target echo signal and the simulated echo signal is used as the input of the signal processing environment. This environment mainly adopts pulse compression,moving target indication and detection technologies to process the echo signal.It is found that the frequency domain method is more desirable for the pulse compression effect than the time domain method,and multi-target range information can be measured from the moving target indication result after using a double delay canceller. A new moving target detecting method is proposed,which can present the positive and negative velocity accurately with the multi-target range and velocity measured simultaneously. Simulation results indicate that the potential targets are detected from the chaotic radar echo signals successfully,and their range and velocity can be figured out correctly in the built radar signal processing environment.展开更多
A real extended scene and moving targets multi-channel Synthetic Aperture Radar(SAR) raw signal simulator accounting for Inertial Navigation System(INS) errors and antenna patterns is presented in this paper. INS erro...A real extended scene and moving targets multi-channel Synthetic Aperture Radar(SAR) raw signal simulator accounting for Inertial Navigation System(INS) errors and antenna patterns is presented in this paper. INS errors are obtained by solving INS error differential equations with Runge-Kutta method. A high resolution SAR image is used to estimate the complex reflectance of real extended scene. Extended scene and moving target are simulated separately and then are superposed in time domain. The simulated multi-channel SAR data can be used for development of multi-channel SAR Ground Moving Target Indication(SAR-GMTI) and also can be used for development of SAR motion compensation.展开更多
Mechanical micro-vibration of a target may induce phase modulations on the radar echo,and the vibration can be detected to identify micro-motion target. In this paper,a new method to detect a micro-motion target and o...Mechanical micro-vibration of a target may induce phase modulations on the radar echo,and the vibration can be detected to identify micro-motion target. In this paper,a new method to detect a micro-motion target and obtain its range and micro-motion frequency is proposed in which multiple periods stepped-frequency continuous-wave signal and Moving Target Indication (MTI) filter are adopted. The simulation results illustrate the validity of this method and present the detection of the target range and the vibration frequency. The experiment gives promising results.展开更多
In order to improve the measurement accuracy of weapons, ultra-wideband(UWB) inverse synthetic aperture radar(ISAR) imaging of high-speed moving targets in short-range is studied. In the scheme, because the positions ...In order to improve the measurement accuracy of weapons, ultra-wideband(UWB) inverse synthetic aperture radar(ISAR) imaging of high-speed moving targets in short-range is studied. In the scheme, because the positions of scatters vary with the radar line-of-sight(LOS) angle when the high-speed target is passing through the closest point of the approach, the concept of equivalent scattering point(ESP) is proposed. The Hough transform is employed to implement ESP motion parameter estimation,while the target translational motion is compensated by using the ESP time delay, and the angle spanned by the target is estimated by utilizing geometric relationship of ESP motion. Finally, the twodimensional image of the target is restructured by using the near field time-domain back-projection algorithm. Simulation results confirm that the proposed method is efficient.展开更多
文摘Aim To propose a generalized and closed representation of the Wigner Ville Hough transform(WVHT), for the moving target detection and imaging in the design of synthetic aperture radar(SAR). Methods Based on the line integral, the WVH transform was derived by combining the Wigner Ville distribution (WVD) and the Hough transform (HT) together. The new transform was then verified with computer by the simulated SAR echoes. Results and Conclusion The correctness and the validity of the WVH transform were proved by the computer simulation. Compared with the conventional WVD HT method, the new approach based on the WVHT can simplify the processing procedure, it can translate the chirp echoes of multi targets of SAR from the time domain into the parameter space directly, while suppressing the cross terms of WVD and estimating the motion coefficients for the final imaging. It is obvious that the WVH transform can be also used in other cases for the chirp signal detection.
基金The"13th Five-Year"Equipment Pre-Research Common Technology Fund of China(No.41411010202)the National Natural Science Foundation of China(No.61571113)the Natural Science Foundation of Jiangsu Province(No.BK20160697)
文摘As the core of a digital phased array radar system,a radar signal processing environment is created to measure multitarget range and velocity information. The radar echo signal is achieved by superposing target echo, noise, clutter and jamming signals linearly. Considering that these signals have many types,two typical combinations are selected to construct the multi-target echo signal and the simulated echo signal is used as the input of the signal processing environment. This environment mainly adopts pulse compression,moving target indication and detection technologies to process the echo signal.It is found that the frequency domain method is more desirable for the pulse compression effect than the time domain method,and multi-target range information can be measured from the moving target indication result after using a double delay canceller. A new moving target detecting method is proposed,which can present the positive and negative velocity accurately with the multi-target range and velocity measured simultaneously. Simulation results indicate that the potential targets are detected from the chaotic radar echo signals successfully,and their range and velocity can be figured out correctly in the built radar signal processing environment.
文摘A real extended scene and moving targets multi-channel Synthetic Aperture Radar(SAR) raw signal simulator accounting for Inertial Navigation System(INS) errors and antenna patterns is presented in this paper. INS errors are obtained by solving INS error differential equations with Runge-Kutta method. A high resolution SAR image is used to estimate the complex reflectance of real extended scene. Extended scene and moving target are simulated separately and then are superposed in time domain. The simulated multi-channel SAR data can be used for development of multi-channel SAR Ground Moving Target Indication(SAR-GMTI) and also can be used for development of SAR motion compensation.
文摘Mechanical micro-vibration of a target may induce phase modulations on the radar echo,and the vibration can be detected to identify micro-motion target. In this paper,a new method to detect a micro-motion target and obtain its range and micro-motion frequency is proposed in which multiple periods stepped-frequency continuous-wave signal and Moving Target Indication (MTI) filter are adopted. The simulation results illustrate the validity of this method and present the detection of the target range and the vibration frequency. The experiment gives promising results.
基金supported by the National Natural Science Foundation of China(61421001)
文摘In order to improve the measurement accuracy of weapons, ultra-wideband(UWB) inverse synthetic aperture radar(ISAR) imaging of high-speed moving targets in short-range is studied. In the scheme, because the positions of scatters vary with the radar line-of-sight(LOS) angle when the high-speed target is passing through the closest point of the approach, the concept of equivalent scattering point(ESP) is proposed. The Hough transform is employed to implement ESP motion parameter estimation,while the target translational motion is compensated by using the ESP time delay, and the angle spanned by the target is estimated by utilizing geometric relationship of ESP motion. Finally, the twodimensional image of the target is restructured by using the near field time-domain back-projection algorithm. Simulation results confirm that the proposed method is efficient.
