A single-feed, cavity-backed, circularly polarized (CP) antenna is designed for wideband wireless applications. The made up of asymmetric crossed bowtie dipoles and achieves broadband characteristics in terms impedance 3-dB axial-ratio (AR) bandwidths. double vacant-quarter printed ring with orthogonal bowties employed CP radiation then combined slot-mode to significantly enhance the operation bandwidth. Measurements an optimized prototype overall size 0.88λ <sub...

This paper investigates the effects of parasitic elements on performance MIMO patch antenna. Multiple square are added in close proximity to each rectangular elements. These affect electromagnetic field distribution and consequently reduce mutual coupling. In addition, wider bandwidth is also achieved. Two antennas coupled H-plane E-plane designed measured demonstrate proposed concept. The results show that both designs have a wide impedance 14% with isolation more than 20 dB across whole...

This paper presents a compact and simple reconfigurable antenna with wide-band, dual-band, single-band operating modes. Initially, co-planar waveguide-fed triangular monopole is obtained wide operational frequency band ranging from 4.0 GHz to 7.8 GHz. Then, two additional stubs are connected the through p-i-n diodes. By electrically switching these diodes ON OFF, different bands can be attained. When turning only one diode, offers dual-band operations of 3.3–4.2 5.8–7.2 Meanwhile, operation...

A method of using a simple single parasitic element to significantly enhance 3-dB axial-ratio (AR) bandwidth crossed dipole antenna is presented. This approach verified by introducing one bowtie-shaped between two arms bowtie dipoles generate additional resonance and thereby broadening AR bandwidth. The final design, with an overall size 0.79 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">o</sub> × 0.27 (λ the free-space wavelength circular...

A novel wideband dual-cavity-backed circularly polarized (CP) crossed dipole antenna is presented in this letter. The exciter of the comprises two classical orthogonal straight dipoles for a simple design. Dual-cavity structure employed to achieve unidirectional radiation and improve broadside gain. In particular, rim edges cavity act as secondary radiators, which contribute significantly enhance overall CP performance antenna. final design with an size 0.57λ <sub...

A dual-wideband circularly polarized (CP) antenna was proposed based on the strategy of combining multimode resonances. The primary radiators were two barbed-shape dipoles and bowtie printed same substrate. They placed over an artificial magnetic conductor (AMC) for low-profile design purpose. Properly fundamental mode dipole, mode, slot second a extra resonance generated by AMC surface, operation can be achieved. final with overall size 0.64λ <sub...

This letter investigates the isolation of a multiple-input–multiple-output (MIMO) antenna system, consisting two circularly polarized antennas with opposite rotating senses. The challenge in achieving high for this type system is analyzed and discussed. Based on this, low-profile wideband design proposed demonstrated, which role decoupling structure also explained. As validation, an prototype fabricated measured. operating bandwidth, <inline-formula...

A compact flexible multi-frequency antenna for smart portable and devices is presented. The consists of a coplanar waveguide-fed slotted circular patch connected to rectangular secondary resonator (stub). thin low-loss substrate used flexibility, stub in the feedline deployed attain wide operational bandwidth. slot etched middle patch, p-i-n diode placed at its center. frequency reconfigurability achieved through switching that distributes current by changing antenna's electrical length. For...

In this paper, a systematic design procedure of compact and broadband circularly polarized (CP) antenna is proposed. The first designed with C-shaped monopole, then slotted patch utilized to produce CP radiation in the lower frequency band. Thus, antenna's overall bandwidth (BW) significantly increased. addition, unlike conventional method which operation verified by simulated surface current distribution, characteristic mode analysis (CMA) carried out give more insight into different modes...

A compact circularly polarized (CP) crossed-dipole antenna for radio frequency identification in the ultra-high is proposed. The consists of two orthogonal dipoles with an arm composed a meander line and triangular-shaped ending achieving size. modified T-match used impedance matching between tag chip. In this design, CP excitation achieved by incorporating semi-circular curves inserted orthogonally arranged dipole arms. final dimensions 35.6 ×35.6 ×0.508 mm <sup...

This paper presents a low-profile circularly polarized (CP) antenna with wideband and polarization-reconfigurable characteristics. The proposed consists of truncated-corner patch working as CP source non-uniform metasurface (MS) acting parasitic elements for performance enhancement. MS is utilized to produce additional operating bands in the higher frequency range, which are then combined lower band produced by driven significantly broaden overall bandwidth. polarization switching mechanism...

This paper presents a simple design of two-element antenna with circularly polarized (CP) reconfigurability for multiple-input multiple-output wireless local-area network (WLAN) applications. A MIMO element consists reconfigurable feeding network, CP source, and 2 × unit-cell metasurface (MS). By controlling the ON/OFF state PIN diodes, proposed system can operate in either right-hand (RHCP) or left-hand (LHCP) all ports, RHCP LHCP each port. For operating modes, exhibits good performance...

This paper presents a method to design compact high-gain multiple-input, multiple-output (MIMO) patch antenna. In one-dimensional large-scale MIMO array, the conventional approach of using multiple patches and decoupling networks significantly increases antenna size. To address this, this utilizes self-decoupled patches, enabling extremely small element spacing while maintaining high isolation levels. Accordingly, size feature can be obtained. Then, gain bandwidth enhancements are realized...

A wideband circularly polarized (CP) antenna with a single feed is proposed for use in global navigation satellite systems. Its primary radiation elements are composed of two orthogonal bowtie dipoles, which equipped double-printed vacant-quarter rings to allow direct matching the <TEX>$50-{\Omega}$</TEX> coaxial line and produce CP radiation. The crossed dipole appropriately incorporated planar metallic reflector desired unidirectional pattern as well achieve characteristic terms impedance...

In this letter, a method to design wideband Fabry-Perot resonator (FPR) antennas is presented. The structure employs closely spaced truncated thin dielectric slabs as partial reflecting surface (PRS). An analytical process based on transmission line theory proposed. criterion for FPR generalized highly PRS, i.e., the PRS only needs exhibit resonance at center frequency of band. Based finding, compact antenna optimized and experimentally validated with wide 3 dB gain bandwidth about 86%...

This paper presents a non-uniform metasurface (MS)-based circularly polarized (CP) antenna that is able to perform with wideband operation characteristic. A squared patch truncated corners was chosen as radiating CP source. Then, unlike the conventional MS antennas uniform MS, proposed design employed placed above driven patch. Apart from increasing impedance bandwidth, also capable of generating two additional bands in high-frequency region, which contributed significantly antenna’s overall...

A circularly polarized (CP) crossed-dipole antenna with switchable rotating sense is presented. The proposed design has two main attractive features. First, a wide overlapped CP bandwidth (BW) realized for both operating states. Second, unlike existing designs targeting similar functionality, no biasing wire through ground plane required, which significantly reduces the complexity. employs parasitic elements different roles. For RF signal, these open an additional resonance band to enhance...

A compact metasurface (MS) based MIMO antenna with wideband operation and high isolation characteristics is proposed for sub-6 GHz applications. single element constructed by a slot coupled 2 × unit cells MS. For mutual coupling suppression, the MS of each grounded at proper positions metallic vias. Compared to other reported designs, possesses several unique features including simple decoupling method no extra space requirement, size, operation. verification, measurements have been...

A circularly polarized (CP) switched-beam antenna array with the capability of generating nine steerable beams in hemispherical space is presented this letter. single radiator first constructed two triangular-shaped dipoles crossing through printed rings, and four parasitic elements are introduced to enhance CP operation bandwidth. For beam steering operation, its antennas implemented a 2 × arrangement fed by four-input port feeding network composed double-box branch-line couplers. With...

A wideband small-footprint circularly polarized Fabry-Perot resonator antenna is presented in this paper. The design employs a partial reflecting surface (PRS) consisting of thin homogeneous dielectric slabs separated by small air gap. PRS analyzed using transmission line theory, which gives more insightful into the theoretical concept and provides simple tool for optimization. An prototype with overall size 1.2λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...

A wideband resonant cavity antenna (RCA) with circular polarisation (CP) and high‐gain characteristics is presented. crossed bowtie dipole used as a primary CP radiator for the RCA. half‐wavelength planar partially reflecting surface utilised to achieve broadside radiation wide axial ratio (AR) well gain bandwidths. The final design yields measured −10 dB impedance 3 AR bandwidths ranging from 5.6 8.4 GHz 6.3 8.15 GHz, respectively. Experimental results also showed an average of 14.5 dBic...