Study On Beam Deflection Technology Of Silicon Waveguide Phased Array

The silicon-based optical waveguide phased array is a new type of optical phased array,which modulates the incident light beam by electrically controlled heating to achieve beam deflection.Compared with traditional mechanical beam deflection devices,silicon-based optical waveguide phased arrays have many advantages such as fast response speed,high deflection accuracy,small size,light weight,low power consumption,and full solid state.There are broad applications and development prospects in the fields of driving,space optical communications and laser weapons.At present,low beam deflection efficiency,single beam scanning efficiency and low search data rate are common problems in silicon-based optical waveguide phased arrays.Therefore,in this paper,starting from the modulation mechanism of the silicon-based optical waveguide phased array,the research on the optimization of beam deflection efficiency and the multi-beam forming method of the silicon-based optical waveguide phased array is carried out.The main research contents are as follows:To study the modulation mechanism of the silicon-based optical waveguide phased array,first introduce the working mechanism of the silicon-based optical waveguide phased array and the composition of the main components;on this basis,take a one-dimensional silicon-based optical waveguide phased array as an example to study the principle of beam deflection of the silicon-based optical waveguide phased array;starting from the thermo-optic effect of silicon material,the phase modulation mechanism of the silicon-based optical waveguide phased array is analyzed,and the relationship between the driving voltage and the far-field beam deflection angle is derived;Finally,using Kirchhoff's diffraction principle,the optical transmission characteristics of the phased array of silicon-based optical waveguides are studied,and a beam propagation model of the phased array of silicon-based optical waveguides is established,which provides theoretical support for the optimization of beam deflection efficiency and the formation of multiple beams.Aiming at the problem of low beam deflection efficiency of the silicon-based optical waveguide phased array,the influence of the element spacing and element width of the silicon-based optical waveguide phased array on the beam deflection efficiency is analyzed;the silicon-based optical waveguide phased array beam deflection is designed the efficiency optimization system has established the corresponding optimization evaluation index;the silicon-based optical waveguide phased array beam deflection efficiency optimization method based on the Alopex algorithm is proposed,and the simulation comparison is carried out with the traditional hill climbing algorithm.The results show that when the number of elements is the same,the proposed method is better than the hill-climbing algorithm in terms of optimization speed and optimization effect.When the number of elements increases,the optimization effect of the hill-climbing algorithm is greatly reduced,while the Alopex algorithm still maintains good optimization effect.Aiming at the problems of single-beam scanning efficiency and low search data rate,based on the two working modes of laser phased array radar multi-target detection and multi-target tracking,two silicon-based optical waveguide phased arrays are proposed:subaperture method and aperture multiplexing method For multi-beam forming methods,the respective far-field beam diffraction models are established,the influence of the two methods on the beam performance is analyzed,and the two methods are simulated and compared.The results show that the sub-aperture method has the same beam scanning range in the multi-beam forming process,but the beam scanning resolution is gradually reduced.This method is suitable for the multi-target detection process;while the aperture multiplexing method in the multi-beam forming process,the scanning resolution the rate remains the same,but the beam scanning range is gradually reduced,which is more suitable for the multi-target tracking process.