Research On High Power Cylindrical Conformal Array Antenna Based On Long Linear Helical Subarray

As the transceiver of high power microwave system,the performance of antenna determines the overall performance of the system at a large extent.With the development of high power microwave technology,the requirement of high power microwave antenna is increasing.Therefore,on the basis of existing research,it is necessary to continuously make high-power microwave antennas develop in the direction of high power capacity,light weight,miniaturization,and conformalization.Among them,the conformal technology has obtained good application prospects in the fields of airborne and shipborne due to its own advantages such as good concealment and strong platform adaptability,and has become an important research direction of antenna technology.As a important branch of the conformal antenna,the cylindrical conformal antenna has the above advantages and can further improve the beam scanning range of the antenna and optimize the overall performance of the antenna.High-power helical array antenna has been proved to have the advantages of high power capacity,certain beam scanning ability,simple design and strong array expansion ability in a series of technical research of high power microwave antenna.However,when the helical array antenna based on the radial line feeding structure is subjected to cylindrical conformal design,due to the size of the radial line itself,it is inevitable that the cylindrical conformal is not ideal.Although it is possible to achieve conformal design by splitting the fronts and using sub-arrays with a smaller number of elements,it can inevitably lead to a highly complicated feed system,which is not conducive to its practical application.To this end,based on the study of high-power radial linear helical arrays,this paper designs and implements a new type of helical array antenna that can be used for conformal antenna arrays by studying Ku-band long linear array helical array antennas.Using this array as a sub-array,a cylindrical conformal high-power radial line helical array antenna design is realized.Firstly,the theory of high-power microwave,array antenna and coupling probe are summarized.The working characteristics of cylindrical conformal array are analyzed,and the overall design framework of the antenna is obtained.Secondly,through the analysis of the rectangular waveguide and the existing probes,the design difficulties of the long linear array antenna feed system are discussed,that is,the probe has a greater influence on the feed system and the difference in unit coupling.After that,on the basis of the original probe,a waveguide wall embedded probe and the overall antenna feed system based on this probe were proposed.Through the relevant simulation research on each part,the design of the Ku-band 80-unit long linear helical array antenna sub-array was finally realized.The experiment shows that the reflection of this long linear subarray at the center frequency is less than-28 d B,the axial radiation gain is 26.1d B,the axial ratio is 1.72 d B,and it has a power capacity of 166 MW while the gain is 24.5d B,the axial ratio is 2.31 d B under measure.Finally,on the basis of the subarray,the feed system design for the cylindrical conformal array is completed.A power splitting system for high-power cylindrical conformal helical array antenna is obtained.The overall simulation model of the high-power cylindrical conformal helical array antenna is completed and simulated,which proves that it has a certain beam scanning ability while having high power capacity and cylindrical conformal capability.