Research On Phased Array And Calibration Network Techniques For The Satellite Application

Combined with specific research projects,this thesis focuses on the research of low coupling phased array antenna and calibration network applied to spaceborne microwave landing system.In the thesis,the concept and application of the designed phased array antenna and calibration network are discussed and the background and significance of the research at home and abroad are discussed.Secondly,the research work of the paper is expounded.Finally,the research results and further research parts of the paper are given.The research work of this paper is divided into three parts.In the first part,the radiation unit of the spaceborne phased array,the 5×5 element subarray and the 16×16 unit array are designed.The simulation results show that the designed radiation unit satisfies the array requirements of the antenna array,the performance of the antenna array reaches the requirement of the technical index,and the second part designs the calibration network.The simulation results show that the performance of the calibration network meets the technical requirements.The third part mainly debug and measure the prototype of antenna array and calibration network.The measurement results show that the measured parameters of antenna array and calibration network are consistent with the simulation results,and meet the requirements of technical indexes.The phased array antenna can be applied to the spaceborne microwave landing system.The research in this paper has very high practical value for the engineering application of phased array antenna.The three research work of this paper can be summarized as follows:?1?Research on low mutual coupling spaceborne phased array antennaAccording to the technical requirements of the spaceborne phased array antenna,the design difficulties of the antenna array are analyzed.At the same time,the basic structure and array mode of the radiation unit are determined according to the related theory of the dipol.The radiation unit reduces the mutual coupling effect between the phased array antenna elements by loading the metal cavity around the dipole,and improves the scanning characteristic of the phased array antenna pattern,while the antenna array is arranged into a uniform planar phased array antenna by 256 radiation units of 0.5?₀×0.5?₀ spacing.The simulation design of radiation unit,subarray and antenna array is carried out with HFSS simulation software.The simulation results show that the designed phased array antenna meets the requirement of line polarization.The mutual coupling between the array units is better than that of-16dB,and the low side-lobe beam scanning can be realized within the range of two 60 degrees,full of the requirements of the space-borne phased array antenna.?2?Research on the calibration network technology of phased array antennaAccording to the technical requirements of calibration network,the design difficulties of calibration network are analyzed.In view of the requirements of space,weight,reliability,coupling amplitude and phase characteristics of the Ku band spaceborne phased array antenna,a calibration network architecture using SIW is proposed.The calibration network adopts internal monitoring method and string feed power divider structure to achieve the characteristics of high reliability and integrated design.The HFSS simulation software is used to simulate the SIW coupler,the cascade feed power divider,the microstrip transfer structure and the 16 element linear array structure with the calibration network as a whole.The simulation results show that total port voltage standing wave ratio of the designed calibration network is less than 1.5 in the working frequency band and the coupling amplitude of the sky line unit and the calibration line is-47±3dB,the phase fluctuation is±7°,which basically meets the requirement of calibration network index.?3?Research on prototype and measurement technology of phased array antenna engineeringAccording to the technical requirements of the spaceborne phased array antenna,the radiation characteristics,transmission characteristics and the measurement principle of the transmission characteristics of the calibrated network are studied,and the corresponding measurement methods are given.Because of the long processing cycle and high cost of the16×16 unit array,the risk factors are uncontrollable.After the completion of the simulation design,the 5×5 sub array is first processed and tested.Through a round of debugging,the final test results are basically consistent with the simulation,and the related design and process problems are solved.Subsequently,a 16×16 unit array prototype was manufactured and tested.Through the analysis and comparison of the test data,the test results are in agreement with the simulation results.It is proved that the design method of the low mutual coupling spaceborne phased array antenna and the calibration network is effective.