Frequency and Pattern Reconfigurable Planar Microstrip Antenna
Ashika K, Anjana Devarajan, PM Amritha, Arjun Saji, Sumi M and Harikrishnan AI
The design of a frequency and pattern reconfigurable microstrip patch antenna is proposed in this paper. The antenna is designed on an FR4 substrate of dielectric constant 4.4 and consists of a circular patch of radius 17.6 mm along with three slits etched on it. Curved stubs are present on either sides of the feedline which help to achieve frequency reconfigurability. Thus, the antenna operates at a single band with a bandwidth of 1.8-2.5 GHz and a dual band resonating at 1.1 GHz and 7.6 GHz, covering a bandwidth of 7.3-7.9 GHz respectively. I-shaped stubs present in the ground plane help to redistribute the surface current and thereby reconfigure the radiation pattern. Six different modes of operations are observed where the radiation pattern switches between unidirectional and bidirectional modes with mainlobe directions 0º,90º,±104º and ±37º degrees. The design and simulation have been carried out using computer simulation technology (CST) microwave studio software and the RLC components have been placed with the aid of CST design studio. The structure shows considerable gain and is suitable for mobile and satellite applications.
Keywords: Feedline, frequency re-configurability, microstrip patch antenna, pattern re-configurability, stubs