Wideband low-profile circular polarized rectangular loop antenna over a mushroom-like EBG structure

Abstract

Abstract:In this paper, a wideband dual rectangular loop antenna over an EBG surface is proposed for low profile wireless applications. A low frequency mushroom-like EBG surface is used as the antenna ground plane. In comparison with a PEC ground plane, design of antenna above an EBG ground plane results in 60% reduction of the structure thickness. The investigated antenna is designed for circular polarization. It is shown that the axial ratio bandwidth (< 3 dB) and return loss bandwidth (< 10 dB) of the dual rectangular loop antenna above the designed EBG surface are 18% and 14%, respectively. The simulated and measured results are in good agreement.

High gain W-shaped microstrip patch antenna

“…As shown in the figure, the maximum achievable gain is 10.46 dBi at the frequency of 2.11 GHz and the gain shows stable performance (above 9 dBi) in the entire operating band. Moreover, the proposed antenna gain is better compare to the designs reported in [3,4]. The measured total efficiency of the proposed antenna is an average of 90% over the operational frequency.…”

“…In this paper, a new W-shaped patch with meander probe fed is proposed. A better gain and low cross-polarization level is achieved compare to design reported in [3,4]. Fig.…”

“…In addition, the presences of slots also restrict the patch currents, at its resonance frequencies that provide lower resonance on the design. This antenna has wider impedance bandwidth in comparison with the rectangular loop antenna described in [4].…”

“…This poses a design challenge for the microstrip antenna designer to meet the broadband techniques [2,3]. There are numerous and well-known methods to increase the bandwidth of antennas, including increase of the substrate thickness, the use of a low dielectric substrate, the use of various impedance matching and feeding techniques, the use of multiple resonators, and the use of slot antenna geometry [4,5]. However, the bandwidth and the size of an antenna are generally mutually conflicting properties, that is, improvement of one of the characteristics normally results in degradation of the other.…”

“…However, it was pointed out [6] that using a higher patch height could cause a higher cross-polarization level. And, the antenna gain drops to 5 dBi, which is lower than other wide-band patch antennas [4,5]. Some other techniques as utilizing the shorting pins or shorting walls on the unequal arms of a U-shaped patch, U-slot patch, or L-probe feed patch antennas, wideband and dual-band impedance bandwidth have been achieved with electrically small size in [7,8].…”