| The moving platform phased array based satellite tracking system plays an increasingly important role in the areas of civil and military,since its ability to track high-speed moving targets in real time.This sports platform mainly refers to the high speed moving target carrier platform of vehicles,ships,aircraft,and missiles.However,due to the existence of the irregular movement of the carrier platform in the satellite communication system,the transceiver array beam might deviate from the satellite,thereby resulting in the instability of the communication.According how to ensure stable communication of the tracking system is a key issue.Both angle measurement and tracking filtering algorithms are the crucial technologies of the system and,both their speed accuracy have a significant impact on target stability and automatic tracking.According to project requirement,this thesis studies the implementation angle measurement and tracking algorithms for the moving platform phased array based satellite tracking system.Specifically,we investigate the principles of the angle measurement and tracking filter algorithms for a self-tracking system.Then,we perform some numerical simulations to assess these algorithms.Finally,we implement the two algorithms on TMS320C6748.Specific research contents are listed as follows.(1)First,we focus on the design of the overall scheme of the self-tracking system.Then,we show the hardware architecture,system workflow and work time of self-tracking system.Further,we expound the solution design of the tracking process.Finally,we depict the structure and characteristics of the TMS320C6748 and the advantages of this floating-point core chip.(2)First,we define the coordinate form of receiving array antenna and derive two angle measurement algorithms.Then,we evaluate the performance of two angle measuring algorithms for both the ideal and non-ideal cases showing their capability of angle estimation.Next,we analyze the angle measurement accuracy of the system,and provide the corresponding high precision methods.Finally,we show the details the implementation of the angle measurement algorithm in the DSP.(3)The principles of three common tacking filtering algorithms are introduced,and the definition of coordinate transformation and motion model are given.We conduct some simulations with respect to α-β filter and adaptive α-β filter and compare their performance,and further introduce in detail how to implement the tracking filter algorithm in current TMS320C6748 self-tracking baseband unit digital board.Finally,we mainly present the interface for DSP and FPGA data communication,the calculation of angle estimation in DSP,the loading process of DSP program and the details of program optimization.(4)Based on the whole moving platform phase array satellite tracking system,the system test has been carried out for each of the above function modules.First,the communication interface between FPGA and DSP is tested,and the correctness of communication module is verified.Then,the hardware experiment is performed to validate the effectiveness of the angle measurement algorithm.By comparing the theoretical value with the measured value,we analyze the feasibility and stability of the angle measurement algorithm.Finally,the self-tracking baseband unit board is tested by constructing a closed-loop simulation test system.Results show that the tracking system can track the target in real time when the vector moves with high speed. |
