Deceptive Jamming for Spaceborne SAR Using Estimated Signal Parameters and Intercepted Signal Phase

Most studies on deceptive jamming for spaceborne synthetic aperture radar (SAR) rely on the modulation-retransmission (MR) mechanism. However, MR-based deceptive jamming has a limitation in terms of setting false target position because it performs jamming after the SAR signal is intercepted at each pulse repetition interval. To address this limitation, we propose a new deceptive-jamming mechanism that emits a deceptive signal before an SAR signal is intercepted. To implement this mechanism, we estimated the SAR signal parameters necessary to design a deceptive signal and determine its emission time. Specifically, we introduce a recursive least squares estimation (RLSE)-based algorithm to estimate the transmission time of the SAR signal and derive the emission time of the deceptive signal using the RLSE result. We also present a deceptive signal model using the estimated parameters and the phase of the intercepted signal. Consequently, the proposed deceptive jamming method can be conducted without prior knowledge of the signal parameters and allows the positioning of the desired targets at various intended locations. The complexity analysis confirms the feasibility of the real-time implementation of the proposed method, and the simulation results demonstrate that the proposed method achieves accurate parameter estimation and ensures the flexible placement of false targets.