水下单光束扫描探测系统光路参数优化设计

针对水下单光束扫描探测系统探测水中近场目标的需求,为抑制海水后向散射干扰,提高系统信噪比,对系统光路参数进行了优化设计。通过推导系统盲区距离公式、水中目标回波和后向散射功率方程,分析了系统探测区域和信噪比同光路参数的关系。在不同水质条件下,基于粒子群算法(PSO)对光路参数进行了优化计算。结果表明:对探测区域为6-10 m的系统,当发射光束与接收视场平行,接收视场半角为9 mrad,收发间距为10.6 cm时,系统信噪比达到最佳。为验证理论模型的正确性,设计了水下激光探测光路模拟系统,测试不同光路参数下系统信噪比,实验结果与理论值一致。优化结果可为水下单光束扫描探测系统光路设计提供理论依据。

Optimization design on optical parameters of underwater single-beam scanning detection system

Aiming at the necessity of underwater single-beam scanning detection system detecting near field target, optical parameters were optimized to suppress the backscatter by sea and improve system SNR. Blind distance formula, echo power equation of underwater target and sea backscatter were derived to analyze the relationship among detection area, system SNR and optical parameters. The optical parameters were optimizationally calculated based on particle swarm optimization (PSO) under different water qualities. The results showed that, for the system detection area was 6-10 m, when the transmitted beam was parallel to receiving field, half receiving FOV was 9 mrad, and the baseline distance was 10.6 cm, the system got the best SNR. To prove the correctness of the theoretical model, optical simulation system of underwater laser detection was designed to test system SNR under different optical parameters, the experimental result was consistent with theoretical result. The optimization results can provide theory basis for designing optical parameters of underwater single-beam scanning detection system.