Summary
International Symposium on Antennas and Propagation
2009
Session Number:3A4
Session:
Number:3A4-4
Simulation of Fractal Shape Geometry for Reflectarray Antenna Design
Farid Zubir, Mohamad Kamal A. Rahim, Huda A. Majid,
pp.823-826
Publication Date:2009/10/21
Online ISSN:2188-5079
Summary:
Microstrip reflectarray consists of planar arrays of microstrip patches with different sizes, shapes and fed by a primarily illuminator, typically a horn antenna [1]. The microstrip patches will be acting as a radiating element whereas it will receive and re-radiate the illuminating power from horn antenna back into space [1]. Since the microstrip reflectarrays have a number of advantages, they have been considered as an attractive object to be discovered and published by researchers from all over the world. The best features of microstrip reflectarray can be partially divided into two points of view which are from electromagnetically and mechanically point of view. From an electromagnetically point of view, they are high gain antennas, low side lobes, capable of beam steering, and from a mechanically point of view, they have lightweight structures, easy to fabricate and manufacture and also robust [2]. In this paper, simulation results of an identical unit cell with different shape of printed radiating element have been briefly discussed. Since the most severe problem in reflectarrays is narrow bandwidth, there are much efforts have been done in recent years to overcome this limitation [3]. There are two factors that causing a narrow bandwidth of the reflectarrays which are the narrow band of the radiating elements and the differential spatial phase delay between elements on the reflectarray itself [4]. The main purpose of this paper is to investigate the suitable shapes of element for a better reflectarray cells development. The suitable shape means it has wider linear phase range and better gradient in degree per micrometer (°/μm) which means the smaller value of gradient, so that when the frequency changes, the phase distribution only varies in a constant which is a little bit in degree (°) for the whole reflectarray structure [4].