For real-time jamming signal generation in deceiving inverse synthetic aperture radar(ISAR),the target characteristics modulation is always processed in the expensive field programmable gate array(FPGA).Due to the...For real-time jamming signal generation in deceiving inverse synthetic aperture radar(ISAR),the target characteristics modulation is always processed in the expensive field programmable gate array(FPGA).Due to the large computational complexity of the traditional modulating operation,the size and structure of simulated false-target are limited.With regard to the principle of dechirping in range compression of linear frequency modulated(LFM) radar,a novel algorithm named "inverse dechirping" is proposed for target characteristics modulation.This algorithm only needs one complex multiplier in the FPGA to generate the jamming signal when the radar signal is intercepted,which can be obtained by multiplication of radar signal samplings and the equivalent dechirped target echo in the time domain.As the complex synthesis of dechirped target echo can be realized by cheap digital signal processor(DSP) within the interpulse time,the overall cost of the jamming equipment will be reduced and the false-target size will not be limited by the scale of FPGA.Numerical simulations are performed to verify the correctness and effectiveness of the proposed algorithm.展开更多
Nonperiodic interrupted sampling repeater jamming(ISRJ)against inverse synthetic aperture radar(ISAR)can obtain two-dimensional blanket jamming performance by joint fast and slow time domain interrupted modulation,whi...Nonperiodic interrupted sampling repeater jamming(ISRJ)against inverse synthetic aperture radar(ISAR)can obtain two-dimensional blanket jamming performance by joint fast and slow time domain interrupted modulation,which is obviously dif-ferent from the conventional multi-false-target deception jam-ming.In this paper,a suppression method against this kind of novel jamming is proposed based on inter-pulse energy function and compressed sensing theory.By utilizing the discontinuous property of the jamming in slow time domain,the unjammed pulse is separated using the intra-pulse energy function diffe-rence.Based on this,the two-dimensional orthogonal matching pursuit(2D-OMP)algorithm is proposed.Further,it is proposed to reconstruct the ISAR image with the obtained unjammed pulse sequence.The validity of the proposed method is demon-strated via the Yake-42 plane data simulations.展开更多
It is potentially useful to perform deception or cover jamming using the rotating angular reflectors since they can form deception echoes along range and azimuth. Inspired by the cohe- rent jamming and micro-motion mo...It is potentially useful to perform deception or cover jamming using the rotating angular reflectors since they can form deception echoes along range and azimuth. Inspired by the cohe- rent jamming and micro-motion modulation, a novel active method is proposed for inverse synthetic aperture radar (ISAR). Radar pulses are sampled and frequency-modulated along azimuth by si- nusoidal signal, and then the jamming signals are retransmitted to the radar and the jamming images are induced after ISAR imaging. Therein, the jamming principle, key parameters and the jamming effect are discussed. The simulated data verify the effectiveness of the jamming method.展开更多
基金supported by the National Natural Science Foundation of China(6127144261401481)
文摘For real-time jamming signal generation in deceiving inverse synthetic aperture radar(ISAR),the target characteristics modulation is always processed in the expensive field programmable gate array(FPGA).Due to the large computational complexity of the traditional modulating operation,the size and structure of simulated false-target are limited.With regard to the principle of dechirping in range compression of linear frequency modulated(LFM) radar,a novel algorithm named "inverse dechirping" is proposed for target characteristics modulation.This algorithm only needs one complex multiplier in the FPGA to generate the jamming signal when the radar signal is intercepted,which can be obtained by multiplication of radar signal samplings and the equivalent dechirped target echo in the time domain.As the complex synthesis of dechirped target echo can be realized by cheap digital signal processor(DSP) within the interpulse time,the overall cost of the jamming equipment will be reduced and the false-target size will not be limited by the scale of FPGA.Numerical simulations are performed to verify the correctness and effectiveness of the proposed algorithm.
基金supported by the National Natural Science Foundation of China(62001481,61890542,62071475)the Natural Science Foundation of Hunan Province(2022JJ40561)the Research Program of National University of Defense Technology(ZK22-46).
文摘Nonperiodic interrupted sampling repeater jamming(ISRJ)against inverse synthetic aperture radar(ISAR)can obtain two-dimensional blanket jamming performance by joint fast and slow time domain interrupted modulation,which is obviously dif-ferent from the conventional multi-false-target deception jam-ming.In this paper,a suppression method against this kind of novel jamming is proposed based on inter-pulse energy function and compressed sensing theory.By utilizing the discontinuous property of the jamming in slow time domain,the unjammed pulse is separated using the intra-pulse energy function diffe-rence.Based on this,the two-dimensional orthogonal matching pursuit(2D-OMP)algorithm is proposed.Further,it is proposed to reconstruct the ISAR image with the obtained unjammed pulse sequence.The validity of the proposed method is demon-strated via the Yake-42 plane data simulations.
基金supported by the Fundamental Research Funds for the Central Universities(K50511020024)
文摘It is potentially useful to perform deception or cover jamming using the rotating angular reflectors since they can form deception echoes along range and azimuth. Inspired by the cohe- rent jamming and micro-motion modulation, a novel active method is proposed for inverse synthetic aperture radar (ISAR). Radar pulses are sampled and frequency-modulated along azimuth by si- nusoidal signal, and then the jamming signals are retransmitted to the radar and the jamming images are induced after ISAR imaging. Therein, the jamming principle, key parameters and the jamming effect are discussed. The simulated data verify the effectiveness of the jamming method.