A CPW-Fed Dual-Band Slot Antenna With Circular Polarization

Abstract

Abstract-In this paper, a coplanar waveguide (CPW)-fed dual-band slot antenna with circular polarization (CP) is presented. In order to achieve CP characteristic, an asymmetric slot and F-shaped end patch are introduced to a conventional rectangular slot antenna. Moreover, by cutting a T-shaped notch on the ground plane, the axial ratio (AR) bandwidth (ARBW) can be extended. The antenna shows left-hand CP (LHCP) radiation in the boresight direction (i.e., +Z direction) at both ARBWs. The proposed antenna is fabricated and measured. The measured results have a good agreement with the simulated ones. The measured impedance bandwidths (|S 11 | < −10 dB) are 1.08 GHz (2.02 to 3.10 GHz, 40% at 2.70 GHz) and 2.31 GHz (4.57 to 6.88 GHz, 39.8% at 5.8 GHz). The two measured ARBWs are 600 MHz (2.60 to 3.20 GHz, 22.2% at 2.70 GHz) and at least 1.15 GHz (4.85 to 6.0 GHz, 19.8% at 5.8 GHz) at the lower and upper bands, respectively.

Characteristic Mode Analysis and Design of Broadband Circularly Polarized CPW-Fed Compact Printed Square Slot Antenna

“…Table 6 shows the comparison of proposed antenna with reported literature on broadband CP antennas. Reported antennas in [4][5][6][7], provide wideband/multiband CP response with small 3-dB ARBW and IBW and relatively large size. The antennas reported in [8][9][10][11][12][13][14][15][16][17][18] provide broadband CP with large physical dimensions, narrow 3-dB ARBW bandwidth, and small gain as compared to the proposed antenna.…”

“…However, in recent years numerous CP techniques have been reported in the literature such as single/dual-feed, fractal structure, and loading of different shapes of strips/slots/stubs on radiating patch and/or ground plane to achieve CP by creating perturbation in electric field which excites two field components of equal magnitude and phase quadrature. Different techniques have been reported in the literature to produce wideband [3][4][5]/multiband [6,7]/broadband [8][9][10][11][12][13][14][15][16][17][18][19][20] circular polarization characteristics.…”

Coplanar Waveguide (Cpw)-Fed Compact Dual Band Antenna for 2.5/5.7 GHZ Applications

“…A CPW-fed slot antenna is realized by embedding a vertical stub with the T-shaped strip and a slit to the ground plane as reported in [22] for realizing dual-band operations. Various dual-band antenna designs include symmetrically introducing four slot stubs on lateral arms [23], by an asymmetric slots in F-shaped end patch [24], by backed ground plane with radial stub on two identical elements [25], by using two parallel monopoles, one curved and one fork-shaped [26], by monopole structure with two inverted U-shaped, L-shaped lateral stubs [27], with two rectangular parasitic elements and an I-shape grounded stub [28], by printed log-periodic dipole array (LPDA) [29], by slots and monopole antenna [30], and by employing meander line technique in [31]. A theoretical and experimental study of twin-slot multilayer CPW-fed antenna is reported in [32], and highly selective behavior and regulation of sharp variations of a discontinuous parallel-plate waveguide with a narrow rectangular ridge filled with axially anisotropic material identified using mode matching technique is achieved in [33].…”