Compact CPW-Fed Circularly Polarized Antenna for Wlan Application

Abstract

Abstract-A novel compact CPW (coplanar waveguide-fed) CPSS (Circularly polarized square slot) antenna is presented. The proposed single-layer antenna is composed of a rectangular ground plane embedded with two equal-size patches along two orthogonal directions. Equal amplitudes with 90 • phase difference values of two patches are capable of generating a resonant mode for exciting two orthogonal E vectors. Axial ratio (AR) bandwidth is significantly enhanced due to slot corner modification. The designed CPSS antenna is compact in nature with volume of 0.37λ 0 × 0.34λ 0 × 0.012λ 0 mm 3 (λ 0 = free space wavelength at centre frequency of the CP bandwidth). It has impedance bandwidth between 4.65-6.72 GHz (36.41%) and 3-dB axial-ratio bandwidth of 520 MHz (4.85-5.37 GHz), which covers 4.9 GHz (802.11j) WLAN for public safety ranging from 4.94 GHz to 4.99 GHz and WLAN (U-NII-1 and U-NII-2A) ranging from 5.150-5.350 GHz for indoor use. The gain variation for the frequencies within the CP bandwidth is also observed to be less than 0.4 dBic. The design is successfully implemented, and measured results are compared with the simulated ones, which are found good agreement.

Microstrip Open-Slot Antenna With Wideband Dual-Frequency and Dual-Sense Circular Polarization

“…As shown in Figure 13, the measured 3 dB AR bandwidths of the antenna can reach 460 MHz at 2. The comparison between the measured performances of the proposed antenna and antennas reported in [8][9][10][11][12][13][14] is listed in Table 2, which includes antenna size, sense of polarization, IBW, and 3 dB ARBW. The proposed dual-frequency dual-sense circularly polarized antenna shows larger impedance and 3-dB AR bandwidths.…”

“…A coplanar waveguide-fed open cross-slot antenna is developed in [10], and 48% wide impedance bandwidth and 8.9% axial ratio bandwidth are obtained. Dual-frequency dual-sense CP is beneficial to the alleviation of multipath interference and fading effects [11][12][13]. A dual-frequency dual-sense circularly polarized antenna realized by designing an F-shaped feeding structure and parasitic elements is presented to achieve AR bandwidths of 22.22% at 1.8 GHz and 10.53% at 3.3 GHz, respectively [14].…”

A Compact Multiband Printed Monopole Antenna With Hybrid Polarization Radiation for GPS, LTE, and Satellite Applications

“…Various kinds of dual-band monopole antennas with different shapes are presented in [8]- [19]. In [8], [9], a singlesense CP is demonstrated while in [10]- [15], dual-sense CP monopole antennas excited by microstrip feedline are presented.…”

A Novel CPW-Fed Planar Monopole Antenna With Broadband Circularly Polarization

“…In order to obtain a wide impedance bandwidth and wide axial ratio bandwidth, a variety of printed monopole antenna configurations have been proposed in research papers [4][5][6][7], designing an L-shaped monopole slot antenna with a C-shaped feed to realized CP operation [4], placing a power division network between a slot and a monopole for generating circular polarization [5], utilizing two parasitic strips to achieve a broadband CP radiation [6], or protruding a G-shaped parasitic strip into a C-shaped monopole antenna to facilitate wide ARBW [7]. Being fed by CPW-fed structures [8][9][10][11][12][13][14], a microstrip antenna can obtain wide operating bandwidth too, and its single metallic layer is better to meet the requirements of low profile and is easier to integrate with the active and monolithic circuits than traditional antennas. By etching modified slots in the ground plane [8][9][10][11], designing two orthogonal equal-size patches [12], or adding parasitic strips [13,14], broadband CPW-fed CP antennas are achieved.…”

“…Being fed by CPW-fed structures [8][9][10][11][12][13][14], a microstrip antenna can obtain wide operating bandwidth too, and its single metallic layer is better to meet the requirements of low profile and is easier to integrate with the active and monolithic circuits than traditional antennas. By etching modified slots in the ground plane [8][9][10][11], designing two orthogonal equal-size patches [12], or adding parasitic strips [13,14], broadband CPW-fed CP antennas are achieved.…”