Abstract
A novel antenna design was configured via a five-stage process. At each stage, a new modified square patch with a half size of that used in the previous stage was added to shape the dual fractal-structure antenna. The antenna had measured dual operating bands (2.4–2.65 and 4.8–6.4 GHz) that meet the specifications of the wireless fidelity (Wi-Fi) and worldwide interoperability for microwave access (WiMAX) applications. The structure of the antenna was carefully analysed to achieve an axial ratio bandwidth of $3\,{\rm dB}$3dB, which was ∼35% of the first operating band and 30% of the second operating band. Right-hand and left-hand circular polarisations were achieved by switching the inputs. The proposed antenna can be used with portable communication devices because of its compact size (18 × 18 × 0.8 mm3) and maximum efficiency (85%) compared with other related antennas.