Research On Key Technologies Of Chirp Continuous Wave Phased Array Radar

The phased array has the advantage of adjusting the beam direction quickly and flexibly.It has always been a research hotspot in academia and industry,and has a wide range of applications in both military and civilian fields.Linear Frequency Modulated Continuous Wave(LFMCW)phased array radar has the advantages of no range blind zone,high detection accuracy and excellent performance in harsh environments.It has received a wide attention and applied as the short-range radar like vehicles radar and short-range defense radar,etc.In this paper,a new system of LFMCW phased array radar based on time-modulated is used.Theoretical analysis,simulated experiment combined with actual engineering verification methods are used to investigate the target detection and target motion parameter calculation of phased array radar under LFMCW signal model discussion.The main work content and contributions are as follows:(1)The principle of time-modulated phase control is introduced.The overall radar scheme is designed based on the LFMCW radar system and the system hardware block diagram is given.Finally,the hardware platform of the LFMCW phased array radar system is built,including the transmitter and receiver of the radar front end,single sideband timemodulated array,etc.(2)The signal processing flow of the LFMCW radar is introduced in detail,and an intermediate frequency signal processing system based on the FPGA+DSP architecture is built for the system.The basic flow of radar signal processing is introduced,including Constant False-Alarm Rate(CFAR),ranging,speed and angle measurement algorithm model,etc.Finally,the algorithm is transplanted to the hardware platform for implementation.(3)A radar visualization system including data transmission,target display and refresh,track display and other functions is completed,and experimental results are given based on actual measurement results.The results show that the system can realize various functions and meet the design requirements.(4)Aiming at the entire phased array system,this article firstly designs each functional module.Then field experiments on the entire radar system is conducted.By comparing the theoretical value and measured value,the feasibility and stability of the algorithm are analyzed,and the foundation for further optimization is laid.