Lens-Less Receiver System Design-Based On Optical Phased Array

With the development of the aerospace,as well as the needs of small drone and individual portable equipment,the traditional lens imaging technology is increasingly unable to achieve the requirements of portability and integration,and the research of new lens-free imaging system is urgent.For the above application requirements,the lens-free receiving chip based on optical phased array is studied,which mainly contents includes:Based on the principle of coherent detection,the structure of the on-chip optical phased array receiver is designed,which consists of the reference path,the receiving antenna and the coherent coupling region.For the reference path,the simulation models of self focus grating coupler,bend waveguide and multimode interferometer are established.The structure parameters of them are optimized to reduce insertion loss.The grating period and the duty cycle of the self-focus grating coupler are optimized.The results show that the coupling efficiency is 44.57 %.The radius of bend waveguide is optimized.The results show that the loss is 0.0026 d B.The width and the length of multimode interferometer section are optimized and the taper is used to reduce the insertion loss.It is simulated that the insertion loss is 0.0376 d B.The simulation model of receiver element and receiver arrays are established.The grating period,the duty cycle and the width of the receiver element are optimized.The results show that the coupling efficiency is 22.95 % with the limited array width.The element spacing of the receiver arrays is optimized.The results show that the coupling efficiency is22.00 % and the field-of-view is 32.76 °.For coherent coupling region,the simulation model of directional coupler is established.The apart of two dielectric waveguides of the directional coupler is optimized.The results show that the loss is 0.1241 d B.The influence of the phase difference between reference and receiving light to directional coupler is studied.For the simulation results,the loss of the reference path and the receiving is calculated,and the capable of chip receiving is estimated.