Aiming at the necessity of torpedo detecting near field target in final stage of guidance, a non-coaxial (transmitter and receiver are not on the same axis) single beam scanning detecting and ranging system has been designed to be applied in torpedo. To study this detection system, this paper proposes a Monte Carlo simulation method for the system. The backscattering signal and target echo signal in seawater is simulated, and then the Signal-to-Backscattering-Noise (SBNR) is calculated. Furthermore, the relationship between maximum detecting distance and system parameters is calculated based on the criterion of minimum SNBR. Finally, the optimal system parameters are determined to get maximum detection range. For verifying the correctness of the theoretical models, underwater laser detection optical simulation system is designed to do target detecting experiment in a basin. The comparative analyses of the simulation and the experimental results show that the simulation results fit the experimental data well, thus the correctness of the semi-analytical Monte Carlo model is verified. The optimal parameters in single beam scanning detecting system can be determined according to the simulation and experimental results. The designed underwater laser detecting system provides a new method for the torpedo to detect underwater target in final stage of guidance.
Development of Scanning Detection System for Cracks on Al2O3 Ceramics.