Cross Dipole Research Articles

A Low-Profile Ultra-Wideband Absorber Using Lumped Resistor-Loaded Cross Dipoles With Resonant Nodes

This article presents the design and analysis of a dual-polarized low-profile circuit analog absorber with wideband absorption characteristics. A lossy frequency selective surface consisting of cross dipole with central resonant node element is used as the top layer, while there is a continuous copper ground as the bottom layer. The novelty of the design lies in the use of the resonant node as it improves the absorption bandwidth by providing an additional resonance without compromising the low-profile nature of the design. It has a thickness of 0.077 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\lambda_{L}$</tex-math></inline-formula> (where <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\lambda {\_}L$</tex-math></inline-formula> is the wavelength corresponding to the lowest operating frequency). The absorber also exhibits a stable absorption characteristics up to 30 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^\circ$</tex-math></inline-formula> angle of incidence and can avoid grating lobes within the operating bandwidth up to 40.79 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^\circ$</tex-math></inline-formula> angle of incidence. An equivalent circuit model is proposed to discuss the operating principles of the design. The validation of the design is done experimentally using the time-gating technique, and a good agreement between the measured and the simulated results is observed. The 10-dB reflection reduction bandwidth and the thickness-to-bandwidth ratio of the absorber are obtained as 108.67% (from 3.58 to 12.10 GHz) and 0.104 from full-wave simulation and 115.67% (from 3.5 to 13 GHz) and 0.098 from measurement, respectively.

Design of miniaturize flexible wideband frequency selective surface for electromagnetic shielding application

In this paper, a flexible, ultra-thin, miniaturized broadband frequency selective surface (FSS) is demonstrated for wideband electromagnetic shielding application. The unit cell of the proposed FSS structure consists of cross dipoles loaded with the metallic circular strip. The proposed miniaturized FSS structure has an extremely low profile with a thickness of and a unit cell size of . This FSS structure provides wideband shielding of more than 20 dB from 1.1 to 2.6 GHz frequency region. Besides this wide stopband, the FSS structure acts as a transparent window in the frequency band which can be used for the 5G communication purpose. Moreover, by comprehending the interaction between the incident electromagnetic wave and unit cell, a conceptual equivalent circuit model is developed that helps to interpret the mechanism of the miniaturization as well as the broadband response of FSS structure. We also compared the proposed FSS with other recently reported structures and observed more than 55% improvement in size reduction with several other miniaturized flexible FSS structure. Furthermore, this FSS structure exhibits 20 dB attenuation over a wide frequency region with a fractional bandwidth of 111%. Moreover, excellent resonant stability is achieved in regards to different polarization and incident angle up to .

C‐/Ka‐band circularly polarized shared‐aperture antenna array

A C-/Ka-band circularly polarized (CP) shared-aperture scanning antenna array has been proposed in this paper. Here, the antenna array working in the C-band (6.48–6.52 GHz) is composed of 4 × 4 cross-dipole antenna elements, and each cross-dipole antenna element is fed by a 1-to-2 power divider with 90° phase difference, so that it can induce left/right-hand CP wave. As for the antenna array working in the Ka-band (27.5–28.5 GHz), it is made up of 16 × 16 CP antenna elements, in which each CP antenna element is an aperture-coupled chamfered patch fed by substrate integrated waveguide (SIW) structure. To realize the proposed scanning array, the C-band antenna array is set within the gap between adjacent antenna elements of the Ka-band antenna array, and the radiation apertures of all the antenna elements are printed on the same plane. Notably, such a layout can yield good isolation performance between the C-band antenna and the Ka-band antenna element. From the measured results, in the C-band, the proposed scanning array can achieve a beam scanning range of 0°–38° with axial ratio (AR) < 3 dB, a port isolation of greater than 45 dB, and a maximum gain of 18.2 dBic. On the other hand, in the Ka-band, the proposed scanning array can yield a beam scanning range of 0°–45° with AR <3 dB, a port isolation of greater than 37 dB, and a maximum gain of 26.2 dB.

A low-profile broadband crossed-dipole antenna with fractal structure and inverted-L plates

A low-profile broadband circularly polarized (CP) crossed-dipole antenna is proposed. In this antenna, the dipole uses a fractal-based structure with multiple similar patches for obtaining broadband CP radiation and impedance matching. The incorporation of the crossed-dipole antenna with four triangular parasitic patches improves both the impedance and axial ratio (AR) bandwidths. Four parasitic coupled inverted-L metal plates are loaded on the ground plane to significantly enhance the AR bandwidth and reduce the antenna profile. The measured results are in agreement with the simulations, which demonstrates that the proposed antenna has a low profile of 0.18 λ0, a − 10 dB impedance bandwidth of 91% (2.78–7.42 GHz), a 3 dB AR bandwidth of 81.5% (2.99–7.1 GHz), and a good right hand circular polarization (RHCP) radiation pattern with an average gain of 7.9 dBi over the whole operating band.

Compact circularly polarized cross dipole antenna for RFID handheld readers/IoT applications

The radio frequency identification (RFID) and global positioning system (GPS) are employed for indoor and outdoor tracking scenarios. This paper presents an amalgamated identification mechanism for sensing and tracking in an Internet of things (IoT) network. A low-profile, compact, multi-functional antenna configuration is proposed for the amalgamation application. The antenna operates in the 915 MHz (UHF), 2.45 GHz, and 5.8 GHz RFID bands, along with the 1.575 GHz GPS L1 band. The presented antenna is a cross dipole configuration consisting of three pairs of dipole elements printed on both sides of the dielectric substrate. The first and third dipole pairs are larger and smaller metal strips with half-arrow shaped ends that excite the 915 MHz and 5.8 GHz bands, respectively. The second dipole pair is an asymmetric triangular-shaped radiator that excites the 1.575 GHz and 2.45 GHz bands. Using quarter wavelength ring delay lines, circular polarization is obtained in each band. The GPS band, in combination with the RFID bands, improves the efficiency and accuracy of the reader tracking device. The proposed multiband antenna prototype is fabricated on the 45° rotated substrate material, resulting in a compact size of 0.21λ0 × 0.21λ0 × 0.004λ0. The antenna simulation and measurement results are in close agreement.

Solar radio bursts observations by Egypt- Alexandria CALLISTO spectrometer: First results

The newly installed CALLISTO spectrometer, hosted by the Department of Space Environment, Institute of Basic and Applied Sciences- EJUST, commenced operation on August 14, 2021. The system contains a cross dipole long-wavelength array antenna with high sensitivity to monitor solar radio transients. Its antenna was strategically positioned and appeared to be in the center of the CALLISTO network of spectrometers. Moreover, in the northern section of Africa, the Egypt-Alexandria CALLISTO and ALGERIA-CRAAG stations are the only ones operating. There are no stations in the West African region, while stations in the eastern part of Africa are not working. Thus, Egypt- Alexandria station serves as a reference for other stations within the e-CALLISTO network. Despite the low solar activity, the instrument detected several solar radio bursts not limited to type II, type III, and type V. A vigorous case study was conducted on two selected radio burst events to validate the authenticity of the recorded events. Other solar radio stations at different geographical locations recorded all the radio bursts detected by the spectrometer. The case study included brief analyses that indicated a type II radio burst observed on October 09, 2021, between 06:30 and 07:00 UT, was associated with an M1.6 solar flare located at N18E08 within NOAA-AR 2882 and a CME with a shock front speed of ∼ 978 km/s. However, the type III radio burst is neither CME nor solar flare associated. These analyses examine the instrument's capacity to provide real-time solar radio transient data 24 h a day to mitigate the challenges of data gaps faced in the African continent. Hence, the instrument has become an integral part of space weather monitoring and forecasting over the region and other parts of the globe.

Design of Wideband Base Station Antenna by Involving Fragment-Type Structures on Dipole Arms

Base station antenna usually requires dual-polarization operation with satisfactory input return loss, adequate dual-polarization isolation, stable gain, and half-power beamwidth (HPBW) in a wide bandwidth covering the entire or part of the mobile communication bands. Such comprehensive requirements provoke great challenges in antenna design. A novel design scheme is proposed by involving fragment-type structures (FTSs) in antenna and seeking for the optimal FTS by multiobjective optimization searching. The technique is demonstrated by improving crossed dipoles for operation in band ranging from 1.7 to 3.8 GHz. Part of the dipole arms can be gridded into cells and reconfigured by using FTS elements. For automatic optimization searching, a binary coding scheme for both the FTS distributions and canonical dipole structure dimensions is proposed. Simulation and measurement show that the optimal crossed dipole antenna may acquire a wide operation bandwidth of 76.3%, with the return loss higher than 15 dB, isolation higher than 30 dB, HPBW of 65° ± 5°, and gain of 9 dBi ± 0.65 dBi for ±45° polarizations.

Efficient Online Data-Driven Enhanced-XGBoost Method for Antenna Optimization

The tremendous progress in artificial intelligence promotes the wide application of machine learning (ML) technology in the field of electronic science. Recently ML-based antenna optimization provides a distinct candidate and attracts considerable attention. However, the large number of training samples generated through time-consuming EM simulations becomes a significant challenge. In this article, an efficient online data-driven enhanced-XGBoost (E-XGBoost) method for antenna optimization is proposed, which is mainly composed of two parts, i.e., an input variable filter module (IVFM) and an antenna optimization module (AOM). Specifically, IVFM serves as a variable sensitivity analyzer, which is accomplished by E-XGBoost to efficiently reduce the dimension of design variable and hence save the training samples. Next, the design variables obtained by IVFM are fed into AOM to find the near-optimal solution. In AOM, an online learning strategy is proposed to train a local E-XGBoost model to evaluate the population in the metaheuristic optimization algorithm (MOA). Compared to the global ML model that can mimic the entire design space, this local E-XGBoost model can further cut down the training samples. To verify the performance of the proposed method, several different antenna examples, i.e., U-slot patch antenna, Fabry–Perot resonant antenna, and dual-polarized cross dipole antenna and 5G MIMO antenna array, are simulated. Numerical results support the proposed method in terms of its superior performance and potential advantage of saving computational overhead.

Suppression of Cross-Band Coupling Interference in Tri-Band Shared-Aperture Base Station Antenna

A triband shared aperture (TBSA) antenna is proposed to meet the new requirements of base station antennas for multiband antennas fusion. The proposed TBSA (P-TBSA) antenna is composed of a lower band (LB, 790–960 MHz) antenna, two columns of middle band (MB, 1710–2170 MHz) subarrays, and a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4\times 8$ </tex-math></inline-formula> array antenna operating at N78 band (higher band (HB): 3.4–3.6 GHz). The LB antenna is located in the center of a shared reflector. The MB subarrays are located around the LB antenna with a side-by-side scheme. The HB array antenna is located below the MB and LB antennas for multi-input–multioutput (MIMO) application. The cross-band coupling interference existing in the P-TBSA antenna can be divided into scattering interference and common-mode interference, which will seriously deteriorate its performance. To suppress the scattering interference, an LB crossed dipole antenna with low radar cross Section (RCS) at both MB and HB and an MB crossed dipole antenna with low RCS at HB are designed. In addition, the method of “path extension” is used to suppress the common-mode interference. By taking the above measures, the distorted radiation pattern of the P-TBSA antenna is significantly recovered.

An SIW-Fed Cross-Dipole Antenna With Broadband Circular Polarization for MMW Applications

In this communication, a broadband substrate integrated waveguide (SIW)-fed circularly polarized (CP) cross-dipole antenna is proposed for millimeter-wave (MMW) applications. Its radiation parts consist of a cross dipole and reflecting ground, which are etched on two substrates. The antenna is fed by an SIW through a double-sided parallel-strip line (DSPSL). In addition, zigzag edges and L-shaped etches are utilized to expand the impedance bandwidth (IBW) and axial-ratio bandwidth (ARBW), respectively. By these methodologies, the antenna prototype possesses a measured IBW of 34.6% from 22.5 to 31.9 GHz, an ARBW of 23.1% from 24 to 30.25 GHz, and a peak gain of 8.8 dBic at 29.5 GHz. In comparison to general coaxial-line-fed cross-dipole antennas with a nonplanar topology and high profile of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.25\lambda _{0}$ </tex-math></inline-formula> ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda _{0}$ </tex-math></inline-formula> is the free-space wavelength at the center frequency), the proposed antenna with PCB process maintains broadband and owns a low profile of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.16\lambda _{0}$ </tex-math></inline-formula> , which makes it more desirable for MMW integrated circuits.

A low profileRFshieldingFSSwith enhanced ultrawide bandwidth range and angular stability

This article describes a frequency selective surface (FSS) for shielding with an improved angular stability over a wide frequency range. The proposed unit design consists of a circular ring in a square element, two cross dipoles, and a T-type slotted structure printed of size 0.052 lambda0 × 0.052 lambda0 on a layer of FR4 substrate having a thickness of 0.0075 lambda0. Here lambda0 is the free-space wavelength of lower cut-off frequency. It has improved the bandwidth range from 2.84 GHz to more than 20 GHz enough to provide effective shielding against the entire ultra-wideband (UWB) range, as well as the X– and Ku–bands. Up to 75 degrees of oblique incidence, the proposed design is polarisation independent and angularly stable. The structure is full wave simulated and an equivalent circuit model is realised. The findings are validated through the use of a fabricated prototype. The applications of shielding are in reducing electromagnetic interference in civil and military applications as well as improving the gain of UWB patch antennas.

Wideband dual-polarized all-metal cross-dipole antenna with feeding column

A wideband dual-polarized all-metal dipole antenna with a novel feeding structure was proposed in this paper. The antenna mainly consists of five parts, which are metal dipole, feeding column, cross feeding sheet, coaxial line and ground plane. A new type of feeding column is introduced between the feeding coaxial and the dipole, which can improve the impedance performance of the antenna at high frequency range. To verify the design, the antenna unit was processed with the size of 0.47λ0 × 0.47λ0 × 0.31λ0. where λ0 is the wavelength of the middle frequency. From the measured results, the antenna achieves a relative bandwidth of 83.5% (3–7.3 GHz) with a reflection coefficient < -10 dB, and the port isolation is greater than 30 dB in the entire frequency band. At the same time, the measured gain of the antenna is 6–9 dBi, the antenna pattern is stable over the entire frequency bandwidth. In addition, the proposed dipole sheet is fixed on a feeding column and is therefore more suitable for working in the C-band or even higher X-band. The antenna adopts an all-metal structure, which is not only suitable for high-power applications, but also more suitable for applications under severe conditions such as strong vibration, high and low temperature.

How Two Crossed Dipoles' Impedance Varies With Their Non‐Orthogonality, Length &amp; Separation

AbstractTo model the electromagnetic mutual impedance between a pair of “crossed dipoles” (a.k.a. “cross dipoles”) whose relative orientation is skewed (i.e., not perpendicular), this paper advances a new modeling approach – the “phenomenological” or “behavioral” approach. This new approach leads to simple models of the mutual impedance, as closed‐form expressions parameterized explicitly by the dipoles' (a) skew angle, (b) separation, and (c) common length. This mathematical simplicity is unprecedented in prior models. These models' usefulness is illustrated, using direction finding as an example.

Ultra-wideband circularly polarized cavity-backed crossed-dipole antenna

This letter demonstrates an ultra-wideband circularly polarized cavity-backed crossed-dipole antenna. It consists of a modified crossed-dipole and a modified cavity. Each arm of the modified crossed-dipole is mainly made up by the combination of a triangle and a fan-shaped sector, and the arms within the same layer of substrate are connected by a vacant-quarter ring. The modified cavity is composed of a rectangular cavity, four coupled rotated vertical metallic plates, and four sequentially rotated metallic steps. Through combining the modified crossed-dipole and modified cavity together, ultra-wideband characteristics in terms of − 10-dB impedance bandwidth (IBW) and 3-dB axial-ratio bandwidth (ARBW) can be realized. The IBW and ARBW are correspondingly calculated to be 128.9% and 121.2%. The prototype of the proposed antenna was fabricated and measured. The proposed antenna has a compact size of 0.74 λ0 × 0.74 λ0 × 0.17 λ0 (λ0 is the wavelength at the lowest frequency of operation band). The measured IBW and ARBW are 125.2% (1.67–7.26 GHz) and 120.1% (1.79–7.17 GHz), respectively, which are in good agreement with the simulated ones. The proposed antenna has stable radiation patterns in the operation band and exhibits a right-hand circular polarization with a peak gain of 12.2 dBic at 6.7 GHz.

Trieste CALLISTO station setup and observations of solar radio bursts

The Trieste CALLISTO station ( http://radiosun.oats.inaf.it ) was established in 2012 at the Basovizza Observing Station (45°38′37′' N, 13°52′34 E'', 398 m above MSL) operated by the Italian National Institute for Astrophysics (INAF) - Astronomical Observatory of Trieste (Italy) to study solar radio bursts and the response of the Earth’s ionosphere and geomagnetic field. To date, three ‘Compound Astronomical Low-cost Low frequency Instrument for Spectroscopy and Transportable Observatory’ (CALLISTO) spectrometers have been installed, with the capability of observing in the frequency ranges 45–80 MHz (from 30 December 2014), 220–420 MHz (from 1 June 2012 to 23 October 2012 and from 5 October 2013), 905–1730 MHz (from 30 December 2019). The three receivers are fed respectively by a dipole, log-periodic and cross-dipole antenna. Nominally, frequency spectra are obtained with 4 sweeps per second over in total 600 channels. Here, we describe the Trieste CALLISTO station setup, the local e-Callisto network digital archive, Trieste CALLISTO Radio Bursts Detection and Visualization System available via web and present dynamic spectra of a sample of Type I, II, III, IV and V radio bursts. As an additional feature, we show also its capability to record lightning strikes.

Theoretical analysis of the role of complex transition dipole phase in XUV transient-absorption probing of charge migration.

We theoretically investigate the role of complex dipole phase in the attosecond probing of charge migration. The iodobromoacetylene ion (ICCBr+) is considered as an example, in which one can probe charge migration by accessing both the iodine and bromine ends of the molecule with different spectral windows of an extreme-ultraviolet (XUV) pulse. The analytical expression for transient absorption shows that the site-specific information of charge migration is encoded in the complex phase of cross dipole products for XUV transitions between the I-4d and Br-3d spectral windows. Ab-initio quantum chemistry calculations on ICCBr+ reveal that there is a constant π phase difference between the I-4d and Br-3d transient-absorption spectral windows, irrespective of the fine-structure energy splittings. Transient absorption spectra are simulated with a multistate model including the complex dipole phase, and the results correctly reconstruct the charge-migration dynamics via the quantum beats in the two element spectral windows, exhibiting out-of-phase oscillations.

Wideband Low-Profile Dual-Polarized Antenna Based on a Gain-Enhanced EBG Reflector

This letter proposed a wideband dual-polarized antenna based on a gain-enhanced electromagnetic bandgap (EBG) reflector. The proposed reflector is studied with a purpose of mitigating the problem of deformed radiation patterns for a mushroom-like EBG reflector backed wideband crossed-dipole antenna, which is caused by undesirable surface current distribution on the patches of the EBG reflector. Introducing the gain-enhanced EBG reflector raises the average broadside gain of the antenna from 4.27 to 8.03 dBi. The antenna is designed to have a working bandwidth of 42.89% (3.04–4.70 GHz) for both ports, with a profile height of 6.26 mm.

A Miniaturized Wideband Dual-Polarized Planar Antenna Based on Multiresonance

In this letter, a miniaturized wideband dual-polarized antenna with a simple structure is proposed. The proposed antenna includes two stacked square loops, which are positioned around the cross-dipole, these loops are utilized to introduce a new resonant mode at a relatively low frequency band, which essentially widens the impedance bandwidth and realizes the miniaturization design. It also includes metallic plates that are vertically positioned on the reflector. These parasitic vertical metallic plates, operating in coincidence with the coupling energy from the nearby radiators, serve to generate an additional resonant mode outside the original impedance passband of the cross-dipole antenna. This enables further expansion of the impedance bandwidth. A prototype was fabricated and tested, where the measured results demonstrated that the proposed antenna ability to achieve a wide impedance bandwidth, i.e., up to 91% (0.98 to 2.6 GHz) with VSWR <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ &lt; $</tex-math></inline-formula> 2. Additionally, the isolation between the two linear orthogonal polarizations was greater than 20 dB. The unidirectional radiation patterns are stable over the entire operating frequency band, with an average gain of 7.5 dBi. Furthermore, the overall size of the proposed antenna is very compact, amounting to only approximately <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\ 0.36\;{{\mathrm{\lambda }}_{\mathrm{L}}} \times 0.36\; {{\mathrm{\lambda }}_{\mathrm{L}}} \times 0.13\; {{\mathrm{\lambda }}_{\mathrm{L}}}$</tex-math></inline-formula> , where <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">${{\mathrm{\lambda }}_{\mathrm{L}}}$</tex-math></inline-formula> is the longest operating wavelength.

Low RCS Dual-Polarized Crossed Dipole Antenna Co-Designed With Absorptive Frequency- Selective Reflection Structure

This article proposes a novel strategy for realizing a reduction in radar cross-section (RCS) of dual-polarized crossed dipole antenna. At first, a compact and polarization-insensitive absorptive frequency-selective reflection (AFSR) structure is proposed by incorporating a bandstop ring resonator within the circular-cross based broadband absorber. The bandstop ring resonator is designed on the backside of the resistive layer due to which a reflection window is realized at a frequency of 8.2 GHz between the two broadband absorptions (4.2-7.0 GHz and 9.2-11.5 GHz). A dual-polarized crossed dipole antenna is designed with operating frequency lying within the reflecting notch of the AFSR structure. A 6 x 6 AFSR structure array is truncated at the center where from which the crossed dipole is connected through a feed substrate. The AFSR structure enacts as a modified ground plane to the crossed dipole antenna. The proposed AFSR integrated antenna achieves an average mono-static RCS reduction of 12.51 dB and 12.62 dB for the TE and TM incident waves, respectively. Further, the AFSR based antenna is also measured for the bi-static RCS, wherefrom the average total RCS reduction of 80% for TE and TM incidence is attained in the frequency band of 4.2 to 11.5 GHz.

Compact and Wideband Crossed Dipole Antenna Using Coupling Stub for Circular Polarization

A novel compact and wideband circularly polarized (CP) crossed dipole antenna is presented. To realize CP radiation, a new design concept of using coupling stub is first illustrated. The coupling stub is equivalent as a combination of a dipole- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${c}$ </tex-math></inline-formula> and dipole- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${y}$ </tex-math></inline-formula> . The dipole- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${c}$ </tex-math></inline-formula> not only couples proper energy from the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${x}$ </tex-math></inline-formula> -axis arranged driven dipole- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${x}$ </tex-math></inline-formula> to the orthogonally arranged dipole- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${y}$ </tex-math></inline-formula> but also provides quadrature phase delay to the dipole- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${y}$ </tex-math></inline-formula> . Therefore, CP radiation is realized for the presented configuration. To improve the input impedance caused by the strong coupling, a long narrow strip is incorporated for the enhancement of impedance bandwidth. Based on the design concept, a compact and wideband CP antenna by using the coupling stub and stepped square loop is developed to further increase the operation bandwidth and realize stable radiation. The designed antenna was finally fabricated for performance verification. Both the simulation and measurement show that the developed antenna can have a wide overlapped impedance and axial ratio (AR) bandwidth from 1.1 to 1.74 GHz with a compact radiator size. In addition, stable antenna gain and radiation patterns are achieved for wireless communications.