Dual‐band circular slot antenna design for circularly and linearly polarized operations

Abstract

The dual-band circular slot antenna utilizing the embedded arc-shaped metallic strip for the circularly polarized (CP) and linearly polarized (LP) operations is presented in this letter. The experimental results show that the resonant frequency of low-band for CP mode is utilized the protruded arc-shaped metallic strip, which extends current route to make the fundamental resonant mode shifted to the lower frequency band. The high-band for LP mode, which has the similar current distribution to that of the fundamental mode of the conventional circular slot, is employed the first-higher order resonant mode of the circular slot. Two measured input impedance bandwidths of the proposed design are 23.2% and 18.8%, respectively, and the measured bandwidth of low-band with an axial ratio (AR) of less than 3.0 dB is 14.5%. The operating bands show the broadside radiation patterns with 1.7–2.7 dBic CP gain and the peak antenna gain of 3.6–4.3 dBi, respectively. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2717–2721, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25562