Design And Implementation Of Key Technology For Internal Calibration Of Tile Type Phased Array

Phased array antennas occupy more and more market share in military and civilian communications due to their high reliability,multi-beam shaping,flexible beam scanning and other advantages.In particular,the tile phased array has the advantages of low weight,small size,easy to conform to the platform,and has become the mainstream of phased array antenna development.Since each channel unit has independent signal amplification and phase shifting functions,the larger the aperture,the higher the system complexity,which makes maintenance work more difficult.In response to the demand for product development projects of XX Company,a tile-type phased array antenna applied to a missile-borne platform was developed.The phased array is inconvenient to be disassembled after installation,so that the radio frequency testability is lowered.For this reason,compared with the traditional phased array antenna,the internal calibration function is added,and the fault can be found in combination with the whole machine design,and the error can be corrected.This paper first systematically investigates the principle,composition and research situation of the tile phased array antenna,and carries out the overall scheme and key technology analysis and design.Secondly,in the millimeter wave tile module design,the mature LTCC scheme is abandoned based on cost considerations,and a low-cost scheme of vertical transition is realized by using a multi-layer microwave board combined with a radio frequency button.The chip selection was completed in combination with the technical requirements and the module RF link was carefully evaluated.A detailed simulation design was also carried out for the RF transition and feed network,and tolerance analysis was performed to reduce the engineering risk.Based on the unit design of the traditional patch antenna,the coupling feeding function is added to the antenna array,and the module and the back-end feeding network are combined to form a closed RF path,which provides hardware guarantee for the internal calibration function.The relevant designs were simulated and optimized,and the feasibility and rationality of the design were verified through physical assembly and testing.By comparing various antenna measurement techniques in detail,the Phase-toggling scheme based on vector rotation method was selected in the near-field calibration according to the requirements,and the calibration work was successfully completed and the performance verification was obtained in the far-field system.The internal calibration network was used to smoothly correct the error of human loading,and the normal performance of the antenna was successfully restored.The tiled phased array antenna and internal calibration function have been fully evaluated and verified.Finally,combined with the research,the application scheme based on built-in closed calibration network and internal and external feed calibration is proposed,which provides a new idea for the performance maintenance of the tile phased array antenna during the life cycle.