A new geometry of wideband circularly polarised antenna with an asymmetric meandered‐shaped monopole is proposed in this communication. The wideband characteristics of the antenna are accomplished by the two asymmetric meandered‐shaped perpendicular arms of monopole and defected ground structure having slanting edge. The proposed prototype offers good performance in terms of impedance bandwidth (close to 102.04% in the frequency range 2.4–7.4 GHz) and the 3 dB axial‐ratio (AR) bandwidth (close to 37.5% in the frequency range 4.9–6.9 GHz). The realised impedance and AR bandwidths cover the WLAN/Wi‐MAX bands and Wi‐Fi band (5.5 GHz).

No abstract

Here, a novel geometry of dual‐band polarisation reconfigurable patch antenna is presented. The proposed prototype design consists of two orthogonal arms as a patch, an inclined slotted asymmetric pentagonal‐shaped ground plane and a PIN diode with a biasing circuit. The polarisation reconfiguration is controlled via ON/OFF states of the PIN diode. The unique feature of the proposed antenna design is that it provides polarisation reconfiguration without considerable deviation in −10 dB impedance bandwidth (IBW) frequency response. The proposed antenna has a measured −10 dB IBW of 49.28% (3.96–6.55 GHz) and 41.47% (4.3–6.55 GHz) in the ON‐state and OFF‐states of the PIN diode, respectively. In the ON‐state of the PIN diode, the antenna exhibits a dual‐band circular polarisation. The first 3 dB axial ratio (AR) band is 4.5% (4.3–4.5 GHz) and the second 3 dB AR band is 17.69% (5.1–6.09 GHz). The proposed antenna exhibits almost uniform gain over the entire operating axial‐ratio bandwidth, with peak CP gain of 2.8 dBic. The suggested antenna has a wide −10 dB IBW, and it is suitable for C‐band wireless applications.

The article proposes design investigation and experimental results of a coplanar waveguide (CPW) fed square slot antenna that gives wideband circular polarization. This circular polarization characteristic is achieved by embedding a square shape stub to left bottom corner and an L-shaped strip to the right upper corner of the slot. A high impedance bandwidth of 87.8 % (3.6–9.0 GHz), a wide axial ratio bandwidth of 73.05 % (4.2–9.0 GHz) and wide 3-dB axial ratio beamwidth of 90° in the entire frequency range of interest are achieved with this antenna structure. To improve the 3-dB axial ratio bandwidth, three slots (two horizontal and one vertical) are scratched at the exterior periphery of the ground plane. These perturbation assemblies are accountable to excite orthogonal modes and help increase an axial ratio bandwidth. The designed antenna displays the constant and steady radiation patterns in the complete frequency range of concern. The overall dimension of the presented compact antenna is 0.24λ × 0.24λ × 0.01λ.

No abstract