Use Offset Dipole In Pulse Instrumentation Radar For Towerless Calibration Method And Application

In order to ensure the instrumentation pulse radar tracking precision and stability,usually require calibration of the task before, the main contents of calibration is thedirectional sensitivity of the radar system and the consistency of amplitude. Thetraditional calibration approach requires calibration tower in complete coordinationwith, this requires the construction of the radar field plateau surrounded by supportingtens to hundreds of meters high tower calibration. With the range of monitoring tasksassume increasingly heavy,,a lot of instrumentation pulse radars, especially mobilepulse radar had been put into use in range, the standard calibration tower constructiondemand brought difficulties to the range security construction,.Various kinds oftowerless calibration technology has become the new development direction. Thepurpose of this paper is in no calibration tower with the case, studies on the no towercalibration method without offset dipole compensation based on, designd towerlesscalibration system, achieves directional sensitivity and consistency of amplitude andphase calibration.The main contents include the following aspects.(1) Research and design the towerless calibration method basing on offset dipolecompensation, With a fixed pulse radar as research object of towerless calibrationsystem, the directional sensitivity and consistency of amplitude are as the main contentof calibration.Through the calibration principle analysis and towerless calibrationscheme selection, presents a new towerless calibration method based on offset dipolecompensation, gives r overall design scheme of towerless calibration system.(2)Research application method of compensation and Installation design. Analysisof offset dipole compensation principle, verify the theoretical feasibility of thetowerless calibration method; according to the structure of radar antenna and feedoutput sum and difference signals analysis, research and design layout of offsetdipole,launch the Installation and test work of offset dipole.verify the practicefeasibility of the towerless calibration method.(3)Develop the calibration signal source of towerless calibration system.Throughanalysis of the related design theory of linear FM signal,adopts the direct digitalfrequency and phase locked loop frequency synthesis technology,develop thecalibration signal source system design of DDS module based on FPGA,and tests the signal source index(4)Develop the towerless calibration system compensation software. On the basisof the original radar software, through the use of software reuse technology and UMLmodeling language,designs and increases the towerless calibration software basing onoffset dipole compensation.Gives the design method and examples of Compensationalgorithm, provides the original parameters for the test and application of system.(5)Lanuch the towerless calibration system test and Through the single carrierfrequency test to determine the towerless calibration point,carries out directionalsensitivity and consistency of amplitude and phase and the towerless calibrationsystem stability. By the fly ball test, satellite and space tracking task,carries outsystem assessment.The results show that:the towerless calibration system is stable,meet the directional sensitivity and consistency of amplitude and phase calibrationrequirements,and the testing error is better than a tower calibration.