Bandwidth-Enhanced Low-Profile Antenna with Parasitic Patches

Abstract

This paper presents low-profile broadband antennas, which are composed of four parasitic patches placed between planar radiators and a perfect electric conductor ground plane. Two types of planar radiators, a conventional dipole and a crossed dipole, are employed to produce linearly polarized (LP) and circularly polarized (CP) radiations, respectively. The radiator and parasitic patches are realized on thin substrates to lower the cost. Owing to the presence of parasitic patches, the antenna performance improves in terms of profile reduction, resonant frequency decrease, and bandwidth enhancement. These improvements are discussed and confirmed computationally and experimentally. The LP design with the overall dimensions of 120 mm × 120 mm × 16.3 mm (0.64λ 0 × 0.64λ 0 × 0.087λ 0 at 1.6 GHz) has a |S 11 | < −10 dB bandwidth of 1.465-1.740 GHz (17.2%), a broadside gain of 8.5-8.8 dBi, and a radiation efficiency > 96%. The CP design, which has the same physical size as the LP case, has a |S 11 | < −10 dB bandwidth of 1.388-1.754 GHz (23.3%), a 3 dB AR (axial ratio) bandwidth of 1.450-1.685 GHz (15.0%), a right-hand CP broadside gain of 7.8-8.7 dBic, and a radiation efficiency > 90%.

Planar and printed antennas for Internet of Things‐enabled environment: Opportunities and challenges

“…Addition of parasitic elements and stacking of patches are yet another way outs to meet the bandwidth issue. A low‐profile antenna, when incorporated with parasitic patches, along with radiators, was seen to improve its bandwidth and decrease the resonant frequency 26 . An H‐shaped slot antenna with infinite ground was found to be enhancing the antenna performance to a good extent 27 .…”

Superstrate-based patch antenna array with reduced in-band radar cross section

“…The electromagnetic energy is coupled from the driven patch array to parasitic patch elements via both the space and the surface waves. The far-field radiation pattern of patch array gets improved on the addition of parasitic elements around the patch array elements [19]. The structure of the antenna with a periodic structure-based superstrate is shown in Fig.…”

Design of a Low-Profile Tripolarized Antenna With Wide Bandwidth

“…As the bandwidth for the monopolar patch is enhanced, the bandwidth of the dipole should also be increased to a compatible bandwidth. In [19], parasitic patches were used to enhance the bandwidth to 14% by exciting the slot between the patches [24]. In the current design, since the target is to reach 25% bandwidth, using parasitic patches is not sufficient.…”