500MHz Archimedes Spiral Wave Absorbing Structure

With the high-speed development of absorbing material,all sorts of use absorbing material absorbing structure of the invention.The wave absorbing structure also develops towards miniaturization.Absorbing material of any thickness,however,will have its corresponding working frequency.So inlow frequency band,absorbing structure will be difficult to achieve the miniaturization and high absorption,especially in the decimeter wave period.Therefore,the miniaturization and low-frequency development characteristics of the absorbing structure have become the industry needs to be gradually improved.Different from the traditional absorbing materials,the helical frequency doubling absorbing structure focuses on using the non-linearity of ferrite to realize frequency doubling.The frequency of the incident electromagnetic wave is doubled to the high frequency band and the Archimedes structure is used to achieve the absorption of the high frequency band.This kind of special wave absorption method is expected to solve the problem of miniaturization of low frequency absorption.In this paper,magnetic ferrite is used as the frequency doubling structure and substrate integrated waveguide is used as the transmission line to collect the incident electromagnetic field.By analyzing the electromagnetic field and its energy loss distribution,S parameter results,and fitting the relationship between the helical frequency multiplier absorbing structure and its absorbing performance,the problem of miniaturization of low-frequency absorbing structure is solved.The following major achievements have been achieved:1.The diode doubler of substrate integrated waveguide is realized innovatively by using the conversion structure of substrate integrated waveguide and microstrip line.It provides a way to realize the nonlinear frequency multiplication and summarizes the related characteristics of the nonlinear frequency multiplication.2.Using magnetic ferrite,a novel frequency multiplier for magnetic ferrite in substrate integrated waveguide is realized.(1)The multiband magnetic ferrite is calculated and tested,and the nonlinear region of magnetic ferrite is obtained.(2)Multimode and single-mode multiband frequency doubler is realized for the substrate integrated waveguide gyromagnetic ferrite frequency doubler.3.Based on the substrate integrated waveguide gyromagnetic ferrite frequency multiplier,the Archimedes spiral frequency multiplier absorbing structure is designed innovatively.(1)The design of Archimedes spiral substrate integrated waveguide magnetic ferrite with multiple frequency absorbing structure in high frequency band is carried out,and the related characteristics of Archimedes spiral absorbing structure are summarized.(2)In low frequency band,the Archimedes spiral substrate integrated waveguide magnetic ferrite with multiple frequency absorbing structure is designed,realizing the Archimedes spiral absorbing structure and realizing miniaturization.