Design Of Tracking Controller Of Multiple Frequency CW Radar And Research On Related Theory And Algorithm

Multiple frequency CW radar has the virtues of high velocity and range accuracy,with the developoment of measureing radar in shooting range,it is paid more attetion to recently.In this thesis,research on related theory and algorithms is carried out based on the design of tracking controller of multiple frequency CW radar,following creative results are achieved:Two new ranging algorithms for CW radar are presented,they are the algorithm of quadratic phase difference and the algorithm of multiple frequency to dual frequency. The principle of the algorithm of quadratic phase difference is discussed in details,the criterion of its frequency design is introduced,and the limitation for output SNR and its ranging accuracy are also analyzed.Simulation is also given,showing that the algorithm reaches high ranging accuracy.The algorithm of multiple frequency to dual frequency is proposed based on the integration of stagger frequency ranging method and dual frequency ranging method.With this aogorithm,the target is firstly captured through stagger frequency ranging method within a long unambiguous distance,then the ranging accuracy is improved through dual frequency ranging method,reaching high range accuracy within a longer range.The three algorithms,including the algotithm of stagger frequency ranging, the algorithm of multiple frequency to dual frequency and the algorithm of quadratic phase difference,are compared with each other,related simulation is also given, laying the foundation for selecting ranging schemes and designing frequency.A new method to improve the precision of velocity measurement of CW radar is peoposed,it's named the method of triangle.The paper introduces the principle of this method,gives the formula of correcting the discrete spectrum with several spectrum lines around the spectrum peak, analyzes its correcting effects changed with SNR and spectrum line numbers used.Simulations under single fixed doppler frequency,paced doppler frequency and random doppler frequency are also given.The method of triangle is compared with energy centrobaric correction method,with the conclusion that method of triangle is less sensitive to noise.The paper analyses the influence of amplitude and phase imbalance on the CW radar's measurements,the formula of system ranging error caused by it is also gven.A new correction method is proposed based on the principle of extracting correction coefficients in frequency domain and correcting the errors in time domain,simulaiton results are also given,showing that the mothed reaches high accuracy of estimating correction coefficients,and the image and DC signals caused by the imbalance of amplitude and phase is constrained effectively after correction.A new scheme for the calibration of zero range in CW radar is introduced and deduced in details,its feasibility and validity is proved.The scheme is also verified through simulations.The influence of acceleration on parameter measurements of CW radar is analyzed,a new real-time acceleration correction algorithm based on partial dechirping for CW radar is introduced,its principles and computional costs are discussed in details.The algorithm is also comapred with acceleration correction algorithm based on total dechirping,with the results that when SNR is met,it attains almost the same effects as the total acceleration correction algotithm,while its computional costs are much lower.The structure of the CW radar and the design of software and hardware of tracking controller is introduced in details,then the trial results including self-testing results and outfield results are given,showing that the tracking controller captures and tracks targets well and achieves high accuracy of parameters measurement.Finally,the paper is summarized and further research of CW radar is forecasted.