Coaxial feed‐type microstrip patch antenna with variable antenna height

Abstract This paper describes a functional antenna with variable antenna height in which the coaxial feed section of the microstrip patch antenna is engineered. This is a new type of antenna combining mechatronic technology and the microstrip antenna so that the resonant frequency of the antenna can be varied by mechanical adjustment of the antenna height. In addition, since the patch can be rotated, the plane of polarization can also be rotated. This antenna has these two functionalities. In this paper, a simple theoretical investigation is carried out on the resonant frequency of the antenna. Further, the experimental results of the test antenna using a conventional dielectric substrate are presented. In the X band, the resonant frequency of the patch antenna can be varied by about 10% when the antenna height is changed by 0.3 mm. Larger variations of the resonant frequency are expected if high‐permittivity materials such as alumina are used as the substrate. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(2): 10–16, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/ecja.10173