Abstract:
To address the issue that single laser directional jamming equipment cannot achieve regional optoelectronic protection due to its limited protection radius, this study proposes a laser redirectional jamming method based on relay forwarding, aiming to expand the protection range of the equipment through coordination between the main station and the relay station.
The study first analyzed the atmospheric characteristics of the main station–relay station transmission link, focusing on the influence of near-ground atmospheric turbulence on laser transmission. Atmospheric turbulence could cause beam jitter, drift, and spot scintillation of the laser, and the degree of its influence was related to the operating wavelength band of the laser. By calculating the coherence length, maximum jitter frequency, and amplitude of lasers in different bands (visible, mid-wave infrared, and long-wave infrared), the constraints of beam jitter parameters on the relay station design were clarified, providing a basis for the subsequent optical system design.
In the optical design of the relay station, two sets of off-axis reflective telescopes with identical magnification and size were used, and a symmetric structure with inverted beam compression and upright beam expansion was employed to achieve all-reflection transmission of multi-band lasers, avoiding aperture obscuration and chromatic aberration. The design parameters included a primary mirror focal length of 379.75 mm and a secondary mirror focal length of 54.25 mm, with the incident field of view designed as ±3′ to cope with beam jitter. To optimize performance, a fast steering mirror was used to compensate for the influence of beam jitter, keeping the system wavefront aberration within λ/10 to meet practical requirements.
Simulation results of laser emission efficiency showed that when atmospheric attenuation and optical component losses were not considered, the laser emission efficiency (such as spot peak intensity and total intensity) of the main station and the relay station was close. Further analysis revealed that the main-station laser divergence angle, relay-station optical transmittance, and atmospheric transmittance needed to be jointly designed. When the atmospheric transmittance was 0.8, the relay-station optical transmittance was 0.9, and the main-station laser divergence angle was 0.12 mrad, the emission efficiency of the relay station could be ensured to match that of the main station.
Field jamming experiments were carried out at a distance of 6 km, in which the optoelectronic imaging device was jammed by lasers directly emitted by the main station and by those forwarded through the relay station respectively. The results showed that both methods could cause the device to produce saturated bright spots, effectively covering the target area and verifying the feasibility of the relay forwarding technology in laser jamming.
In conclusion, through theoretical analysis, optical design optimization, efficiency simulation, and field experiments, this study confirms that relay forwarding technology can expand the protection range of laser directional jamming equipment, offering a new solution for regional optoelectronic protection and providing an important reference for the further application of relay forwarding technology in the field of laser jamming.