Research On Key Technology Of Optical Phased Array Servo Control

With the rise of the autonomous driving field,lidar as the most important component of autonomous vehicles has received extensive attention and research.Among them,solid-state lidar with optical phased array as the main core has become a research hotspot in the field of lidar due to the advantages of concentrated main flap energy,strong anti-interference ability and rapid response.However,due to the influence of the optical phased array fabrication process and insufficient research on the scanning technology,there are still many problems in the practical application of optical phased arrays to achieve high quality beam scanning.In order to solve these problems,the beam scanning control principle of optical phased arrays needs to be studied,and the main performance indicators of optical phased arrays need to be experimented and analysed.Therefore,this paper designs a particle swarm algorithmbased servo control system to study the actual performance of optical phased arrays.The particle swarm optimisation algorithm is used to find a set of voltage values with optimum beam quality through negative feedback adjustment,which is applied to the phase shifter of the optical phased array for phase delay regulation,and plays an important role in improving the outgoing beam quality of the optical phased array and realising the beam scanning function.In this paper,a survey of the background and current status of optical phased arrays is first carried out,and the current research status of optical phased arrays at home and abroad is described.For the current subject research of optical waveguide phased arrays,the composition structure and characteristics are introduced,which are composed of four parts:grating coupler,beam splitter,phase shifter and emission grating,and the theoretical model of each part is established.In order to study the main parameter indicators of the optical phased array and the related influencing factors,the influence of the number of array elements,array element spacing and deflection angle on the far-field optical intensity radiation distribution is explored by means of Matlab simulation.The particle swarm algorithm is used to simulate the one-dimensional optical phased array model to prove the feasibility of the particle swarm algorithm.Based on the theoretical study and simulation experiments,a set of servo control system and experimental scheme for the optical phased array are designed.The experimental results show that the servo system can control the optical phased array for better beam scanning between-9° and 9°.When the scanning angle is-9° to 9°,the main flap width can be steadily controlled between 0.32° and 0.44°,and the side flap rejection ratio can be steadily suppressed above 8d B,indicating that the servo system solution can effectively control and calibrate the angle of the optical phased array,thus realising the scanning function and laying a foundation for the application of optical phased array chips in the engineering field.