A Cross-Eye Jamming Mitigation Approach for Polarized Monopulse Radars

In this letter, a retrodirective cross-eye jamming mitigation method is proposed. Because the cross-eye jamming signals are transmitted by the active jammer antennas, and the target returns are reflected by a moving target with complex scattering structures, the polarization fluctuation of the target returns is more significant than that of the jamming signals. By weighting the sum channel and the difference channel of a polarized monopulse radar to cancel the target returns spatially, the energy ratio between the target returns and the jamming signals in the weighted outputs decreases, which means that the polarization fluctuation of the outputs decreases as well. When the weighting vector is searched, the polarization fluctuation of the weighted outputs reaches the minimum. Then, the current weighting vector can be linearly transformed into a target angle estimate. The proposed method has low computational complexity and good antijamming performance, especially under a high jamming-to-signal ratio.