Research Of Airborne And Shipborne VHF Broadband Miniaturized Antenna

VHF band has been widely used for the wireless communications of aircraft and ships. However, the size of conventional VHF antenna is too large because of its wavelength. Spread spectrum and frequency hopping technology requires the bandwidth of the antenna should be at least wider than that of the hopping. Consequently, research of VHF airborne and shipborne broadband and miniaturized antenna is topic with theoretical and practical significance.This paper introduces firstly the significance and research situation of airborne and shipborne VHF broadband and miniaturized antenna, and then the basic knowledge of antenna and methods of broadband and miniaturization, providing theoretical knowledge for the design in this paper. This paper studies sleeve antenna and analyzes the principle of traditional sleeve antenna and some improved sleeve antenna. Then on basis of that a sleeve antenna with new structure is proposed, which adopts rectangular and diamond sleeve and some methods such as thickened radiator and elevated feed point. The new antenna decreases its dimension and widens its working band. Then loaded antenna is used to improve the properties of the antenna further. Then several antennas are simulated and optimized by CST Microwave Studio software. The best dimensions are achieved by parameter sweep and characteristics such as radiation pattern and gain are analyzed. Finally, according to the results of the simulation, several antennas are manufactured and tested by some related equipments, and the tested results are in accordance to those simulated. The proposed antennas in this paper have both good electric and physical characteristics, which meet the requirements of airborne and shipborne VHF broadband miniaturized antenna.