| Phased Array Antenna with its fast beam scanning ability and other characteristics, is widely used in angle tracking system. "Onboard phased array satellite platform self-tracking system" is for the stability between the missiles and other high-speed movement of the platform and the relay satellite two-way information transmission needs to carry out the auto-tracking technology research of onboard platform-dimensional active phased array satellite.In the tacking system, two-dimensional angle measurement is one of the key technologies.In the process of angle search or angle capture, angle tracking, angle measurement is applied.The accuracy of angle measuring directly affects the precision of angle tracking. Combined with the project requirements, this paper focuses on the discussion and research of two-dimensional fast angle measuring algorithm using in the tracking system, and finishes the microwave dark room experiment. The feasibility and effectiveness of two-dimensional fast angle measuring algorithm is verified by the experiments.Main work includes the following points:(1)The structure and system solutions of phased-array satellite tracking system are designed,and the hardware architecture,data processing and system workflow of tracking system are given out.Then several key processes are expounded, including: angle search/capture process,angle tracking process,work timing system.(2)The principle of phased array antenna is introduced, planar array of phased array is analysed, and the antenna beam control is expounded.The key technology of project application: phantom technology of digital phase shifter is analysed and studied.Then the impact of the digital phase shifter quantization error is analysed.(3)The two-dimensional angle measurement algorithm is discussed.The array form and coordinate system definition of the system are cleared.Two-dimensional angle measurement algorithm is derived.The processing method is divided into direct method and indirect method.The method used in this system is narratived.Then the angle measuring algorithm is simulated,divided into ideal and non-ideal situation.In the ideal situation, SNR,snapshot number and angle of incidence is considered for the accuracy of angle measurement.In the non-ideal situation,the amplitude and phase inconsistencies are considered.And the error source of amplitude and phase inconsistencies is analysed.(4)The microwave dark room experiment is done for validating two-dimensional angle measurement algorithm.The data acquisition hardware and receiving antenna installation used in the experiment are introduced.Then the experimental operation method and data processing methods are explained.By comparing the theoretical value and measured value,the feasibility of two-dimensional angle measurement methods is analyzed.Through five different set experiments,azimuth angle and pitching angle of measuring accuracy,the impact of measuring error under the different code rate and transmission power,system robustness are verified.The actual measurement is consistent with the theory and the correctness and feasibility of the angle measurement method are verified. |
