This paper addresses the issue of deceptive jamming against synthetic aperture radar (SAR) by using 1-bit sampling and time-varying threshold (TVT). With 1-bit intercepted SAR signal, the multipliers involved in a convolution is replaced by xnor gates, which considerably simplify the jamming signal generation. Moreover, the TVT is used for 1-bit quantization before retransmission to retain the relative amplitude information of the jamming signal. As a result, the proposed deceptive jamming schemes are superior to their conventional counterpart in terms of realization. Effects of harmonics and oversampling are analyzed to evaluate the performance degradations caused by the 1-bit sampling and TVT. Simulation results are provided to confirm the validity of the proposed schemes.

Deceptive SAR Jamming Based on 1-bit Sampling and Time-Varying Thresholds

Deceptive jamming against synthetic aperture radar (SAR) is a topic of great interest in the SAR electronic countermeasure during the past decade. However, most of the existing jammer techniques concentrate on the jamming signals of the extended static scenes. Actually, the jamming signals of the moving targets are also highly desired to be included in order to protect the military moving targets. For this problem, this paper proposes an efficient deceptive jamming method of both static and moving targets against SAR. An equivalent range equation is first developed, which can precisely take into account for the motion with fixed velocity, even with constant acceleration. Then, a 2-D spectrum corresponding to target-dependent part in the jammer’s frequency response based on the range equation is derived. Finally, the efficient deceptive jamming can be achieved by the fast Fourier transform, Stolt interpolation, and complex multiply, thus significantly reducing the computation complexity. In addition, practical implementation is also considered in this paper. Compared with its counterparts, it can generate the jamming signals of moving targets precisely and efficiently even in the case of high squint angle and long synthetic aperture. Simulation results are presented to validate the proposed method.

Efficient Deceptive Jamming Method of Static and Moving Targets Against SAR

Due to the rapid progress of electronic countermeasures (ECMs), the corresponding means of electronic counter countermeasures (ECCMs) are urgently needed. Due to its range-dependent feature, frequency diverse array (FDA) radar technology possesses the application potential for mainlobe jamming suppression. However, the construction of the jamming model for FDA radar is a critical and challenging problem that has not been sufficiently studied. In this article, based on the exact understandings of the time parameter and time-range relationship, the existing deceptive jamming models are analyzed and the correct modeling process is concluded. Furthermore, the complete signal processing flow related to the range parameter in the FDA radar is presented. Consequently, a novel deceptive jamming (NDJ) approach for FDA radar is proposed. NDJ can obtain the same beamforming gain as the target to avoid being suppressed at the beamforming level. Subsequently, effective deceptive jamming can be generated at different range bins to degrade the detection performance of the radar. Simulation examples demonstrate the effectiveness of our proposed method.

A Novel Deceptive Jamming Approach Against Frequency Diverse Array Radar

The traditional synthetic aperture radar (SAR) deceptive jamming can effectively create false static and moving targets in the SAR image. However, the deceptive capability could be significantly reduced or denied by the two-channel SAR-ground moving target indication (GMTI) system. To achieve the effective deception, the impact of SAR deceptive jamming against two-channel SAR-GMTI system is first analyzed. Then, a novel effective deceptive jamming method based on two jammers is described. Using this method, the two stationary jammers are made to be located at different positions along the azimuth direction. By applying the complex modulation in each jammer, the additional phase term of the synthetic jamming signals in the two coregistered SAR images is canceled. It is shown that the expected modulation coefficient for each jammer can be precisely calculated by solving a linear system of equations of two unknowns. Finally, the proposed deceptive jamming against the two-channel SAR-GMTI system is achieved by generating the jamming signal in each jammer via the efficient deceptive jamming technique. By utilizing the optimal layout of the jammers, this scheme is both robust and computationally efficient. It will generate false static and moving targets with high fidelity in the two SAR images. Only the false moving targets can be detected by the displaced phase center antenna (DPCA) and then relocated to the correct positions by along-track interferometry (ATI) in the two-channel SAR-GMTI system. Some simulations are provided to demonstrate the effectiveness of the proposed method.

A Novel Deceptive Jamming Method Against Two-Channel SAR-GMTI Based on Two Jammers

Deceptive jamming template synthesis for SAR based on generative adversarial nets

In this paper, a novel deceptive jamming signal generation method against the space-borne Synthetic Aperture Radar (SAR) is proposed for the electronic warfare (EW) system. By using the off-line parallel computing for jamming modulation function in the distributed sub-scenes, the proposed algorithm can highly reduce the computation burden of extended scenes for real-time deceptive jamming. The measured data from an experimental jammer system and the simulation results are used to demonstrate the performance of the proposed method. It is shown that the proposed method provides reliable jamming performance and can be implemented in real-time application.

A novel jamming signal generation method for deceptive SAR jammer

This letter presents a novel scheme for moving target deception jamming (MTDJ) against multichannel synthetic aperture radar (SAR)-ground moving target indication (GMTI) based on multiple jammers. The multichannel SAR signal models for the real and false moving targets are established first. Then, the proposed MTDJ method based on multiple jammers is derived according to the principle that the interferometric phase matches the across-track velocity of the moving target. To ensure efficient deception jamming and to resolve the accurate scattering coefficient modulated in each jammer, the interferometric phase of the false moving target is decomposed into two parts, one is the term that matches the across-track velocity, while the other is the additional term generated by each jammer. Hence, the expected modulation coefficient in each jammer can be determined based on the additional interference phase cancellation. Finally, the proposed MTDJ is realized by generating the jamming signals in each jammer via the efficient deception jamming technique. The simulation results demonstrate the effectiveness of the proposed MTDJ method.

Effective Moving Target Deception Jamming Against Multichannel SAR-GMTI Based on Multiple Jammers

Radar target/environment simulators are usually developed for testing and evaluating various radar systems. In this paper, we present a novel implementation of real-time radar environment simulator with four channels for missile-borne Synthetic Aperture Radar (SAR). By using wideband Digital Radio Frequency Memory (DRFM) technique and parallel computing technique based on the Field Programmable Gate Array (FPGA), the simulator can provide real-time computation capability for raw SAR echo signal generation of extended scenes with a very small computational delay, which is essential for the missile-borne radar Hardware-in-the-Loop (HIL) simulation. Based on the multichannel and multi-DRFM architecture, the simulator is able to simultaneously generate multichannel SAR echo signals together with jamming signals. Moreover, the simulator is highly scalable and reconfigurable, and is able to meet a various kinds of radar simulation requirements.

Qingyang Sun

Papers

Efficient Deceptive Jamming Method of Static and Moving Targets Against SAR

A novel jamming signal generation method for deceptive SAR jammer

A Novel Deceptive Jamming Method Against Two-Channel SAR-GMTI Based on Two Jammers

Effective Moving Target Deception Jamming Against Multichannel SAR-GMTI Based on Multiple Jammers

Development of multichannel real-time Hardware-in-the-Loop radar environment simulator for missile-borne Synthetic Aperture Radar