Experimental Study Based On The Range Gated Laser Imaging

In the field of aerospace and military, the application of miniature all-solid-state laser imaging radar has a very high value. Compared with other means, laser imaging technology can take both intensity image and range image which bring benefits to the target recognition. The range-gated imaging technology is a major laser imaging system of the focal plane imaging. With theoretical analysis, simulations and experimental studies, this thesis analyzed the adaptability range of two methods of range-gated imaging system, which are laser imaging methods of gated slice and gain modulation.First of all, in theoretical aspect, through the analysis of the models of laser radar equation, SNR and detection probability, we determined the relationship between various parameters of imaging system, and discussed the role of these various parameters in laser imaging distance and accuracy.Secondly, based on the theoretical analysis of mathematical model, we simulated the range-gated laser imaging. In the first place, the complex three-dimensional model was established by using 3DMax software, which is the imaging target in the simulation. After that, VC++ and OpenGL procedures were used to extract information of the three-dimensional model. At last, numerical simulation had been done with Matlab based on the mathematical model, and the simulated radar images had been obtained. Based on the simulation, we analyzed the range precision of the imaging system.Then, in experimental aspect, under the existing equipment and the current conditions of laboratory, we built a range-gated laser imaging system. The system includes three modules, which are transmitter, receiver and synchronous control system. The functions of each imaging modules were explained and the performance of the main imaging device were analyzed.Finally, based on the laser imaging system, we conducted a range-gated laser imaging experiment. The experimental data were processed and synthesized 3D images. The range precision of the imaging system was obtained from the experiment. The results indicated that, the range precision of the 700 meter distance gated slice imaging can achieve 1 meter; 60 meter distance in gain modulation can make the range precision better than 1 meter.