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A novel retrodirective cross-eye system based on microwave photonics is proposed. The scheme utilizes a dual-parallel Mach–Zehnder modulator (DPMZM) to modulate the RF signal received at the left (right) end onto the same optical fiber, transmits the optical signal to the right (left) end, and converts the optical signal back into RF signal by a photodetector (PD). By controlling the bias voltage of the main modulator of two DPMZMs, the phase of the transmitted RF signal can be reversed and the amplitude of the transmitted RF signal can be adjusted. The scheme has large working bandwidth and low cost. Only generating two-phase inverted signals is not enough to implement effective cross-eye jamming. It is necessary to consider nonideal conditions and the impact of echoes on jamming in order to obtain practical technical solutions. The scheme exhibits good robustness, as the relative phase of two jamming signals remains insensitive to bias drift. The scheme provides flexibility in controlling the signal amplitude to meet the requirements for angle deception. From the phase-front distortion perspective, an analysis of the impact of cross-eye parameters on the deception angle is conducted. In the experiment, the transfer functions in the 4–27-GHz frequency range are provided. Through hardware-in-loop simulation, the capability of the scheme to effectively deceive the monopulse radar is validated. Discussions and analysis are conducted on the dynamic cross-eye jamming process and the impact of target echoes on the cross-eye jamming performance. Parameter optimization and control strategy for the scheme are investigated with the impact of target echo considered.

In this paper, a photonic approach for the generation of wideband radar jamming signal with flexible tunability is proposed and experimentally verified. In the experiment, interrupted-sampling jamming, comb spectrum modulation jamming, and compound jamming is established upon the received radar signal, respectively. The jamming effectiveness is evaluated through cross-correlating the radar jamming signal with the received radar signal. The cross-correlation results show that variable number of false targets can be generated based on our proposed scheme and the number of the false targets can reach 40. It is worth to note that our approach solves the issue of power loss in traditional interrupted-sampling jamming. Meanwhile, the low-frequency jamming seed signal used in the experiment is quite easy to obtain in electrical domain. The proposed scheme has a stable, compact, and efficient structure, which meets the requirements of the electronic warfare systems and will get potential applications in future electronic warfare systems.