Design And Experiment Of Receiving System For Optical Waveguide Phased Array Laser Radar

Having advantages of small volume, low driving voltage, large scanning angle, and high scanning speed, optical waveguide phased array (OWPA) has a wide application prospect in the laser radar (ladar), medical imaging, laser processing and other fields. It has become an important direction in the research of optical phased array technology. Ladar is a combination of modern laser technology and the radar technology. Compared with the traditional radar, ladar has a very high frequency resolution, spatial and temporal resolution, and the advantages of small volume, light weight. Ladar has been widely applied in the target detection and tracking, imaging and recognition. Therefore, it should be of significance to investigate the application of OWPA to ladar for expanding the OWPA technique and promoting the performance of ladar.For the characteristics of the OWPA scanning system, an optical receiving system based on direct detection method is designed. In the system, linear array APD detector is used, before which a single aperture telescope with wide field of gaze is developed to collect the target signal. Moreover, micro-lens array (MLA) is adopted to increase the utilization ratio of echo energy of APD arrays. First, the overall design scheme is put forward, and the specific parameters of the system are designed. Based on the principle of maximum signal-to-noise ratio (SNR), the receiving system is optimally designed. The best working point of APD detector and the receiving system bandwidth is optimized. The performance of the designed system is first analyzed in theory; and further the transmittance, field of view, responsivity, noise characteristics, the received SNR, and the detection probability of the system are measured experimentally and evaluated.Using the OWPA beam scanning system and the receiver system, the principle system OWPA ladar is designed, and the methods of target distance and angle measurement are analyzed, and the experimental system is constructed based on the signal detection circuit and host computer control software. The target detection experiment is also carried out in the laboratory. The time delay, space and time synchronization, and target location of the ladar system are tested and analyzed.The results show that the designed and realized receiving system has the advantages of small size and compact structure, and the performance index can meet the needs of detection of the optical waveguide phased array ladar. The research results are valuable and can be referred to in the design and development of the practical application system.