In laser-guided weapon systems, the backscattering of the seeker is an important factor affecting the guidance accuracy and operational stability. Backscattering, simply put, refers to the phenomenon where, during the transmission of the laser emission signal, when it encounters air particles, smoke, water vapor or the medium around the target, part of the light is reflected and travels back along the original emission path, eventually entering the receiving optical path of the seeker.
For laser tracking guidance heads, backscattering can affect navigation. During normal operation, the guidance head relies on receiving the laser echoes reflected by the target to achieve positioning and tracking. However, the backscattered light superimposes with the actual target signal, which will lead to a decrease in the signal-to-noise ratio of the detector. This can result in an increase in tracking errors in the mild cases, or even cause signal saturation, loss of the target, and even lead the guidance system to mistakenly identify interference signals as the target, thereby directly affecting the combat effectiveness.
To reduce the interference from backscattering, various measures are usually adopted in engineering. Firstly, the optical system design is optimized by using narrowband filters to suppress non-target band stray light and improve the selectivity at the receiving end. Secondly, pulse modulation technology is employed to distinguish the near-field scattered light from the far-field target echoes through time gating circuits, thereby reducing near-field interference. Thirdly, the laser emission power and divergence angle are optimized to ensure the detection capability while reducing unnecessary scattering energy.
With the development of precision guidance technology, the requirements for the anti-interference capability of the guidance head have been continuously increasing. In-depth research on the formation mechanism of backscattering, and the improvement of the guidance head's adaptability in complex environments, are of great significance for enhancing the reliability and combat effectiveness of laser-guided weapons.