Research On Link Performance Of Microwave Photonic Phased Array System

The phased array radar has fast beam scanning speed and high detection sensitivity.However,the working bandwidth of traditional phased array radar is relatively narrow,and it is difficult to meet the performance requirements of radar in complex environments.Therefore,the use of optical true delay network instead of traditional phase-shifting network can effectively increase the instan-taneous bandwidth of the radar and eliminate its effects under wideband signals.Beam skew effect.At the same time,in order to reduce the volume and complexity of the system,the application of integrated photonics technology to optical phased array radar has become a new development di-rection.This paper studies the engineering realization of a two-dimensional integrated optical true delay phased array system,including delay network design,optical true delay line technology,fo-cusing on the link gain,noise figure,dynamic range and antenna beam pointing angle error And other performance indicators.Starting from the basis of phased array radar and the basic principles of phased array antennas,this thesis introduces light-controlled phased array antennas,demonstrates the advantages of optical true delay technology in the field of phased array radars,and briefly analyzes the optical radio frequency Basic principles and performance indicators of the link.On this basis,a two-dimensional true delay phased array network is proposed,which uses a silicon-based integrated binary delay line to effectively reduce the complexity of the delay network.Based on the theoretical analysis of the feasibility of the optical phased array radar system,the system performance index is also a key issue.The thesis combines the proposed true delay network and starts from the system link to conduct theoretical analysis and simulation calculations.Then on the basis of the above analysis,the design experiment tested the relevant parame-ters of the 8×8 phased array antenna system,including the gain,noise figure,dynamic range of the system link,and the beam direction of the system,and simulated calculations.The results are compared and analyzed.Taking a single link in 64 channels as an example,in the 2?6GHz fre-quency band,the RF gain has a minimum of 11.7d B and a maximum of 14.9d B,which is within4d B of the theoretical calculation value;the system noise figure is below 24d B;The dynamic range is 90.5 d B·Hz^2/3;the maximum deviation of the actual beam pointing angle of the system is 4°,which includes Link fiber length cutting error and antenna array element pattern error.The paper research and experimental results verify that the proposed two-dimensional phased array system link performance can achieve high pointing accuracy under the premise of basically meeting the requirements,and provides corresponding improvement directions and directions for subsequent phased array system link design.