The Design And Implementation Of C-Band Radar Calibration Signal Source

Based on the application background of C-band fire control radar performance calibration in an air defense weapon system,this paper develops an efficient,fast and accurate radar calibration aiming at the technical problems of measuring axle center deviation between radar electric axis center and weapon system optical axis center and artillery firing dispersion center caused by impact vibration of marching state and aging or replacement of active components during operation.The design and development of calibration source provide powerful technical support for rapid and accurate calibration of radar development,use and maintenance.The calibration source is based on rectangular calibration method and frequency synthesizer technology.The trial-produced radar calibration source has good environmental adaptability,small size,light weight and easy installation.It can effectively calibrate the errors of radar optoelectronic axis and ranging system,and better solve the problems of radar field calibration and basic function test.At present,it has passed the appraisal entered the stage of small batch production.The main contents of this paper are as follows:1.The basic principle of radar calibration is studied.According to the advantages and disadvantages of various calibration methods,the overall technical scheme of external trigger hybrid frequency synthesis calibration source is proposed.The DDS and PLL frequency synthesis involved in the calibration source are mainly studied.2.Hardware circuit module design,including the selection of main components and the design of circuit connection of LO I PLL,LO II PLL,Ethernet PHY,DAC,FPGA and up-conversion link.The design of PCB and physical photos is shown..3.Logic module design.The logic development environment is introduced,and the top-down method is used to describe the top-level logic design.The logic design of GM4704 B,GM4384 PLL configuration,Ethernet communication,waveform generator and other functional modules,as well as the logical test and verification results of each functional module are emphatically described.4.The display of radar calibration source design results.Index test and functional verification are introduced.Some laboratory test results are introduced.When the output signal is 6660 MHz continuous wave,the SSB phase noise is lower than-93dBc/Hz@ 1kHz,and the spurious level is lower than-66 dB.The indicators basically meet expectations,meet technical requirements.The radar calibration source is also combined with the main radar,and the statistical results show that the radar calibration source can effectively calibrate the photoelectric axis and zero distance of the radar.