Study On The Surface Switching Of Large Shaped Antennas

The large shaped antenna has unique performance advantages in target detection in complex work environments and specific areas because of its remarkable characteristics such as high gain,high isolation,and low sidelobe in the target radiation area.Large shaped antennas have increasingly stringent requirements on the accuracy of the reflective surface in the development of large-diameter and high-frequency bands,and the radiating electrical performance of the shaped area antenna on the target area is greatly affected by the shape of the reflective surface,the shape of the target area and the antenna frequency,so it is necessary to use different shaped surface types to make the antenna work under different working modes to ensure the electrical performance of the antenna.In order to ensure that a large shaped antenna can use different antenna shapes in different working modes,precise switching of the antenna surface shape of the shaped surface under different working modes is particularly urgent and important.So this paper do research for imprinting large surfaces precise antenna switching problems,research done as follows:(1)Analyze the research methods and methods for precise switching of different surface shapes of large shaped antenna,and determine two key technical problems that need to be solved in the process of surface-type switching: precise reconstruction of the surface of the shaped antenna and calculation of the telescopic adjustment of the actuator when the different surfaces are precisely switched to each other.Firstly,a large number of related scientific research literatures are reviewed for the exact reconstruction of the profile,and the existing surface reconstruction methods(wavefront method,mouth-surface field optimization method,direct-expansion reconstruction method,etc.)and profile reconstruction algorithms are summarized.Comparing the characteristics and applicability of different surface reconstruction methods,an optimal method for accurate reconstruction of large shaped surface antenna surface is finally obtained.(2)Determine the precise reconstruction method for large shaped antenna surface based on LSM and Zernike polynomials,and give the basic ideas,specific steps and derivation formulas for the precise reconstruction method of the profile.And using LSM and formula method two reconstruction methods to verify the accurate reconstruction of the 8-meter and 110-meter shaped antenna surface examples.The correctness of the reconstructed equations is verified by the proposed method,and the reconfigurable equations of the shape-rectangular antenna satisfying the requirements of reconstruction accuracy are obtained.This can pave the way for the accurate switching of the shaped antenna surface.(3)The method for determining the amount of the actuator adjustment in the precise switching of large shaped surface is studied.For the specific adjustment example about the surface is changed from the shape of the shaping surface to the paraboloid surface of large shaped antenna,the best fitting paraboloid is the equivalent surface of the shaped surface,determining the panel support node position of the actuator,combining with the minimized actuator telescopic adjustment distance,calculate the actuator adjustment when surface adjust from the best-fit paraboloid to the position of the target parabolic surface through space transformation of the shaped antenna.Based on the electromechanical coupling theory,it is verified whether the far field radiation pattern of the shaped antenna after the surface switching has satisfied the electrical performance requirements.Finally,the correctness of the precise switching method is verified by the example of the 110 m shaped surface antenna facing the paraboloidal surface switching..(4)Based on C++Builder software and MATLAB,a software computing platform was established to determine the shape reconstruction equation and adjust the surface shape switching of large shaped antenna,obtaining accurate and computationally efficient shaped antenna calculation software.Modularization of the algorithm used in the two parts of the antenna surface reconstruction and surface switching adjustment to simplify the calculation process,through the visual interface to complete the shape of the antenna reconstruction and surface shape adjustment process,calculating the relevant parameters and saving the calculation results,which can serve the engineering application requirements of the shaped antenna in the actual service process,and improve the operating efficiency.Large shaped antenna is facing tough challenges with the urgent requirements of large diameter,multi-band,multi-target and complex working environment.The accurate surface reconstruction and accurate surface adjustment are important guarantees and necessary measures for high-quality far-field radiation performance of large shaped surface antennas under different working modes,it has great reference significance and application value in the process of large shaped antennas.