A chirp-mismatch echo signal can be generated by exchanging the I and Q baseband signals of a received SAR signal. In this paper, the basic generation principles of a chirp-mismatch echo signal are analyzed. Then, a suppression jamming method with controllable jamming position and coverage area is proposed. This method firstly performs chirp-mismatch processing on the received SAR signals, then controls the range jamming coverage and center position through range shift-frequency modulation and time delay, and controls the azimuth jamming coverage and center position through motion modulation and azimuth shift-frequency modulation. Theoretical analysis and simulation results show that this method can effectively control the location and coverage of a jamming result without convolution modulation, and it is easy to implement in engineering. The simulation results verify the correctness of the theoretical model, which can provide a basis for the implementation and application of SAR jamming based on the active radar transponder.

Two approximations are used in "Three-pass" D-InSAR (Differential SAR Interferometry). First, in this paper, the error caused by the approximations is deduced and defined as First-order Approximation Error. Then, the characteristics of First-order Approximation Error are discussed in theory and proved by two experiments. In the end, three viable and effective methods are put forward to correct approximation error.