Printed Monopole Antenna Research Articles

A novel UWB in‐body printed microstrip feed monopole antenna with dual band‐stop capabilities

AbstractThis paper presents an innovative and condensed blueprint for an ultra‐wideband (UWB) printed monopole antenna, aiming to augment bandwidth and achieve dual band‐stop capabilities, all while accounting for the impact of the human body model on stop bands. The proposed design showcases a square radiating patch situated on the top layer of the substrate, complemented by a ground plane etched on the underside, integrating two sets of adapted U‐shaped slots. Such a configuration delivers a broad operational fractional bandwidth that surpasses 132%. Within our design, a modified C‐shaped slot in the radiation patch creates the first band‐stop property, while a pair of modified F‐shaped slots etched in the radiation patch generates the second stop‐band property. Measuring 12 mm × 18 mm × 0.8 mm, the antenna offers a compact form factor, broad bandwidth, cost‐effectiveness, omnidirectional radiation patterns within the H‐plane and acceptable behavior for using in In‐body microwave applications.

Design of a Compact and Wideband Printed Monopole Antenna With Stable Omnidirectional Radiation Patterns

Design of a Compact and Wideband Printed Monopole Antenna With Stable Omnidirectional Radiation Patterns

A metasurface-inspired printed monopole antenna for 5G and RF energy harvesting application

In this paper, a wideband circularly polarized (CP) Y-shaped printed monopole antenna with the twin parasitic conducting strips (PCS) loaded with a circular-shaped metasurface (MS) layer is investigated. Initially, a linearly polarized (LP) Y-shaped monopole antenna is designed. Thereby, to attain a CP from LP, a metallic strip is used to short one of the parasitic conducting strips to the ground plane. Further, a circular-shaped MS of a radius of 1.25λ∘, is placed just below the radiator at a height of 0.33λ∘, which enhances the impedance and axial bandwidths, as well as the CP antenna gain, with a motive to achieve the performance trade-offs from an application perspective. So, it is fabricated on FR-4 substrate with a dimension of 1.33λ∘×0.9λ∘×0.02λ∘ (λ∘ = 5 GHz) & offers the measured impedance bandwidth of 2.58 GHz (3.27–5.85 GHz, 48.45%), axial bandwidth of 860 MHz (4.24–5.1 GHz, 19.67%), CP gain avg. of > 8.75 dBic, & antenna efficiency of > 80% in the desired frequency band (3.5/5 GHz). In addition to the fundamental analysis pursued here, CP is presented in the form of a distinctive gain-bandwidth product relationship, which has been noted as being very rare in the existing literature, especially for 5G communications (sub-6 GHz) and RF energy harvesting applications.

A wideband X‐band circularly polarized printed monopole antenna backed by AMC reflector for 5G/IoT CubeSat applications

AbstractThis letter presents a coplanar waveguide‐fed printed monopole antenna backed by an artificial magnetic conductor (AMC) reflector. The proposed monopole antenna achieves circular polarization by loading the monopole with a printed coil and using an asymmetric ground plane. In addition, the AMC increases the antenna gain while maintaining a wide axial ratio (AR) bandwidth. The unit cell of the AMC is based on a Minkowski‐like prefractal geometry. The antenna is fabricated and measured with a total size of 1.07 λ0 × 1.07 λ0 × 0.25 λ0 at the operating frequency of 8.5 GHz. The measured results show a wide −10 dB impedance bandwidth of 26.9% (7.12–9.38 GHz), a wide 3 dB AR bandwidth of 22.23% (8–9.89 GHz) as well as a peak gain of 8.3 dBi at 8.5 GHz. This is significantly better than comparable antennas in addition to this design being the smallest in size.

Two new single/multi-objective multi-strategy algorithms for the parametric estimation of dual band-notched ultra wideband antennas

This article introduces a novel single objective and a multi-objective multi-hybrid naked mole-rat (moIGDN) algorithm optimization techniques for solving numerical benchmarks and electromagnetic engineering problems. The hybridization was introduced to overcome the basic naked mole-rat algorithm’s (NMRA’s) local optima stagnation and poor exploration problems. The global exploration search equations of INFO, gazelle optimization algorithm (GOA), and dwarf mongoose optimization algorithm (DMO) have been added into the NMRA’s worker phase. Additionally, five mutation operators have been introduced for parametric enhancements and adaptations. For single-objective performance evaluation, three benchmark datasets namely classical benchmark, CEC 2014, CEC 2017, and CEC 2022 have been analysed. A comparison with JADE, SaDE, CMA-ES, success history based DE (SHADE), fractional-order calculus-based FPA (FA-FPO), LSHADE-SPACMA, NL-SHADE-LBC, evolutionary algorithms with eigen crossover (EA4eig), S-LSHADE-DP, L-SHADE-RSP-MID, EBOwithCMAR, LSHADE-EpSin among others. Apart from that, the proposed moIGDN algorithm was utilized to optimize the design of two electromagnetic multi-objective printed monopole antennas categorized as basic ultra-wideband (B-UWB) and dual band-notched ultra-wideband (DBN-UWB) antennas. Simulations have been performed by using the EM-MATLAB optimization interface with two objective functions: trying to minimize pass-band signal reflection and maximizing antenna gain, by mapping solutions to the Pareto-front boundary in the objective space. The best obtained antenna structure had an impedance bandwidth of 2.92–11.96 GHz (fractional bandwidth of 122%), efficient band-rejection characteristics for the WI-MAX (3.3 GHz–3.7 GHz) and WLAN (5.15 GHz–5.85 GHz) bands, and a compact geometry. Based on simulation results, moIGDN is found to be effective and can be utilized to solve complex wireless communication and advanced engineering optimization problems.

A novel and compact ultra‐wideband printed monopole antenna with enhanced bandwidth and dual‐band stop properties

AbstractThis article introduces a novel and compact design of an ultra‐wideband (UWB) printed monopole antenna with an enhanced bandwidth and dual band‐stop performance. A modified π‐shaped slot has been inserted in the ground plane to exhibit a wide impedance bandwidth of 116% (ranging from 3.1 to 11.2 GHz), whereas dual stopband responses (at 3.5 and 5.5 GHz) are obtained by embedding three I‐shaped stubs and a pair of modified Γ‐shaped slits in the radiating patch. The proposed topology is highly compact having an overall dimension of 18 mm × 14 mm (which is equivalent to 0.7λg × 0.54λg, where λg is the guided wavelength corresponding to the lower resonance band), has a low fabrication cost, an ultra‐wide impedance bandwidth, and omnidirectional radiation patterns in the H‐plane, which make the antenna appropriate for wideband applications and integration into UWB system. To check the advantages of the proposed antenna, experimental verification has been carried out as well as the results are compared for UWB scenarios.

Investigation of a Circularly Polarized Metasurface Antenna for Hybrid Wireless Applications.

The increasing prevalence of the Internet of Things (IoT) as the primary networking infrastructure in a future society, driven by a strong focus on sustainability and data, is noteworthy. A significant concern associated with the widespread use of Internet of Things (IoT) devices is the insufficient availability of viable strategies for effectively sustaining their power supply and ensuring their uninterrupted functionality. The ability of RF energy-harvesting systems to externally replenish batteries serves as a primary driver for the development of these technologies. To effectively mitigate concerns related to wireless technology, it is imperative to adhere strictly to the mandated limitations on electromagnetic field emissions. A TA broadband polarization-reconfigurable Y-shaped monopole antenna that is improved with a SADEA-tuned smart metasurface is one technique that has been proposed in order to accomplish this goal. A Y-shaped printed monopole antenna is first taken into consideration. To comprehend the process of polarization reconfigurability transitioning from linear to circular polarization (CP), a BAR 50-02 V RF PIN Diode is employed to shorten one of the parasitic conducting strips to the ground plane. A SADEA-driven metasurface, which utilizes the artificial intelligence-driven surrogate model-assisted differential evolution for antenna synthesis, is devised and positioned beneath the radiator to optimize performance trade-offs while increasing the antenna's gain and bandwidth. The ultimate prototype achieves the following: an impedance bandwidth of 2.58 GHz (3.27-5.85 GHz, 48.45%); an axial bandwidth of 1.25 GHz (4.19-5.44 GHz, 25.96%); a peak gain exceeding 8.45 dBic; and when a highly efficient rectifier is integrated, the maximum RF-DC conversion efficiency of 73.82% and DC output of 5.44 V are obtained. Based on the results mentioned earlier, it is considered appropriate to supply power to intelligent sensors and reduce reliance on batteries via RF energy-harvesting mechanisms implemented in hybrid wireless applications.

Design of Miniaturized Printed Spiral Monopole Antenna

This paper introduces the design, simulation and implementation of miniaturized printed monopole antenna for medical application. FR-4 substrate dielectric constant 4.3, and thickness 0.8 mm have been used. The proposed antenna operates in Medical Implant Communication System (MICS) band. It has a spiral shape with an overall dimension of (9x9x0.8) mm3. The proposed antenna was simulated and evaluated using the CST microwave studio package. The simulation results show that the designed antenna operates at a frequency of 401.3MHz with a return loss of (-10.904 dB) and bandwidth (3.9 MHz). The proposed antenna structure was fabricated and experimentally tested. Results of simulation and implementation show that the proposed antenna possesses a miniaturized dimensions and acceptable performances, enabling their use in medical applications

Characteristic modal analysis in miniaturization and bandwidth‐enhancement of monopole antenna for WLAN/WiMAX/LTE applications

AbstractThis work presents a printed monopole antenna with a miniature size and enhanced wideband using characteristic mode analysis (CMA). The printed monopole antenna structure comprises one vertical and one horizontal monopole, and a ground plane with a vertical extension. By connecting the horizontal monopole to the ground plane extension through a via hole, a significant enhancement in bandwidth is achieved in both lower and high bands. A 105% increment in bandwidth is achieved with the via hole compared to without it. The influence of the via hole is analyzed using CMA to provide a physical insight into the design. The proposed antenna is compact with an electrical size of 0.01 λ2, leading to a miniaturized design.

A circularly polarised multiple input multiple output antenna with single‐sense for sub‐6 GHz 5G applications

AbstractIn this study, a compact wideband circularly polarised Multiple Input Multiple Output (MIMO) antenna with the two parasitic elements is proposed. The printed monopole antenna for wideband circular polarisation proposed in authors' previous study is used as an antenna element. One‐sided substrate reflector is installed at the back side of the antenna, positioned 0.2λ0 away, to improve the gain. The circularly polarised radiation, deteriorated by the influence of mutual coupling of two antenna elements and reflector, is improved by deploying two parasitic elements on the bottom layer of the antenna's substrate. The antenna's size is 0.99λ0 × 0.32λ0 and the reflector's size is 1.41λ0 × 0.82λ0 (λ0 is the free‐space wavelength at lowest operating frequency). The measured bandwidth of 10 dB impedance with a 3 dB axial ratio is 33.49% from 3.53 to 4.95 GHz, which can be utilised for sub‐6 GHz 5G applications. The simulated and experimental results are compared to validate the antenna characteristics.

Small-size multiband printed monopole antenna for wireless applications

AbstractA small-size multiband antenna with 14 bands is presented in this paper for wireless applications. The studied antenna mainly consists of a folded monopole antenna and an M-shaped structure. Furthermore, the antenna has a simple design with a compact dimension of 26.8 × 10.8 mm2. The studied antenna is printed on FR4 substrate with a depth of 0.8 mm and fed by a coaxial cable. The −10 dB bandwidths measured are 210 MHz (1200–1410 MHz), 100 MHz (2200–2300 MHz), 193 MHz (3000–3193 MHz), 180 MHz (3330–3510 MHz), 390 MHz (4110–4500 MHz), 4971 MHz, 577 MHz (5300–5877 MHz), and 700 MHz (7100–7800 MHz), which can cover 3G/4G/5G/Wi-Fi/WiMAX, C, and S bands. The gain and efficiency of the presented antenna are 1.3–4.00 dBi and 46%–60.2%, respectively.

High-gain printed monopole antenna with dual-band characteristics using FSS-loading and top-hat structure

In this paper, a printed monopole antenna with high-gain and dual-band characteristics for applications in wireless local area networks and the internet of things sensor networks is presented. The proposed antenna consists of a rectangular patch with multiple matching stubs surrounded to improve the impedance bandwidth of the antenna. The antenna incorporates a cross-plate structure which is seated at the base of the monopole antenna. The cross-plate consist of metallic plates aligned perpendicularly which enhances the radiations from the edges of the planar monopole to maintain uniform omnidirectional radiation patterns within the antenna’s operating band. Furthermore, a layer of frequency selective surface (FSS) unit cells and a top-hat structure is added to the antenna design. The FSS layer consist of three unit cells printed at the back side of the antenna. The top-hat structure is placed on top of the monopole antenna and comprises of three planar metallic structures arranged in a hat-like configuration. The coupling of both the FSS layer and the top-hat structure presents a large aperture to increase the directivity of the monopole antenna. Thus, the proposed antenna structure realizes a high gain without compromising the omnidirectional radiation patterns within the antenna’s operating band. A prototype of the proposed antenna is fabricated where good agreement is achieved between the measured and full-wave simulation results. The antenna achieves an impedance bandwidth |S11| < − 10 dB and VSWR ≤ 2 for the L and S band at 1.6–2.1 GHz and 2.4–2.85 GHz, respectively. Furthermore, a radiation efficiency of 94.2% and 89.7% is realized at 1.7 and 2.5 GHz, respectively. The proposed antenna attains a measured average gain of 5.2 dBi and 6.1 dBi at the L and S band, respectively.

A Wearable Localized Surface Plasmons Antenna Sensor for Communication and Sweat Sensing

This paper presents a novel wearable antenna sensor based on localized surface plasmons (LSPs) for communication and non-invasive sweat monitoring. The sensor is made up of corrugated plasmonic structures based on the conventional printed monopole antenna, which achieves multi-band and miniaturization. The physical dimensions of the antenna sensor are 35 × 34 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , with a thickness of only 0.13 mm. Simulated and measured results demonstrate that the proposed antenna sensor covers triple operating bands, including 2.4 GHz and 5.8 GHz ISM bands, as well as high frequency ultra-wideband ranging from 7.89 GHz to 9.56 GHz. The antenna sensor exhibits a good radiation pattern with a peak gain of 3.02 dBi and a high quality factor (Q) up to 35. The use of polyimide as a dielectric substrate enables the antenna sensor to achieve flexibility and conformality, maintaining stable operating states even when bent and deformed. The specific absorption rate (SAR) values in three frequency bands are simulated and evaluated to ensure its safety for human health. Moreover, the resonant frequency of antenna sensor significantly shifts with the volume and concentration of sweat, indicating that the proposed sensor is highly sensitive to sweat volume and concentration with a sensitivity of 120 MHz/1mm and 4.57 MHz/1, respectively. The proposed wearable antenna sensor is a promising candidate for a sweat monitoring system for athletes or patients, allowing for health monitoring at any time and place.

A novel compact and broadband printed monopole antenna for circular polarization

In this letter, a compact and broadband printed monopole antenna for circular polarization is proposed. In order to reduce the antenna size and achieve the circular polarization, the ground plane is combined by two elliptical shaped conductors with different size, and the antenna is designed asymmetrically to the microstrip line. The simulated and measured bandwidth of the 10dB-return loss with a 3dB-axial ratio is 57.9% (2.65GHz-4.81GHz) and 52.0% (2.45GHz-4.17GHz). The size of the antenna is 0.178 λc2 (λc is a wavelength in free space at the center frequency).

A broad axial ratio bandwidth and wide angle coverage circularly polarized monopole antenna for wireless communication

AbstractA uniquely shaped layout of a wideband circularly polarized (CP) printed monopole antenna is planned in this article. The proposed antenna comprises a 7‐shaped slotted radiating patch, tapered feed line, and modified partial ground plane. Multiple parasitic strips are employed at optimum positions on the ground and radiating planes to improve the axial ratio bandwidth (ARBW). The electrical dimension of the designed antenna is . The confirmed −10 dB impedance bandwidth (IBW) and 3 dB ARBW are 11.86 GHz (3.14–15 GHz), 130% and 6.32 GHz (4.04–10.36 GHz), 87.78% along with coverage angle. The proposed antenna is suitable for different applications in communication systems such as WLAN, WiMAX, FM CW altimeter, and satellite for C‐ and X‐ band.

UHF-Printed Monopole Filtenna for Partial Discharge Detection with LTE Signal Suppression

External partial discharge (PD) sensors for the ultra-high frequency (UHF) method are widely used to detect the PD signals in high-voltage power equipment for ease of installation and maintenance. However, conventional external PD sensors detect not only PD signals but also LTE signals; thus, a microwave filter is usually employed. In this work, a UHF filtering antenna (filtenna) is proposed as the external PD sensor to detect PD signals and simultaneously block LTE-band signals. The proposed UHF filtenna is the printed monopole antenna with a built-in interdigital bandpass geometry, which is selected for its compact size. Measurement results show that the proposed UHF-printed monopole filtenna operates adequately in the frequency range of 1 GHz to 1.6 GHz and simultaneously blocks LTE signals significantly.

Wideband, Wearable, Printed Monopole Antenna System for Integration into an Electromagnetic Radiation Evaluation Device

This paper describes the design steps carried out to prove the concept of a wideband monopole antenna system to be used in a wearable device conceived for the evaluation of electromagnetic field radiation. Such a device is envisaged to be integrated into protective vests worn by professional users in their working space environment as part of intelligent multi-risk protection. Initially, the main characteristics of a simple straight monopole are reviewed to serve as a reference. A modified octagonal monopole antenna element is introduced, and a two dual-linearly polarized configuration of such monopoles is designed, fabricated, and tested to be used in the frequency range of 0.7-3.5 GHz. The expected radiation characteristics (input reflection coefficient and isolation between vertically and horizontally polarized ports) are confirmed experimentally. The effects of a thick lossy foam substrate layer used to mitigate the presence of the metal shield, employed in the vest lining as a Faraday cage protection, are analyzed both by simulation and experimentally. Finally, electromagnetic simulations are carried out to confirm that a system of five dual-linearly polarized monopole elements located in the chest, shoulders, back, and helmet of the user can provide an adequate estimation of the incident electromagnetic field radiation.

Circularly polarized edge‐placed printed monopole antenna using theory of characteristic modes

AbstractThis article presents a method of using modal analysis to characterize the circular polarization (CP) performance of a printed monopole antenna. The radiator and feedline are positioned on the edge of the substrate and fed accordingly at the edge, and a modified ground plane is employed. The complete antenna without excitation is analyzed using characteristic mode theory to provide physical insight into its CP operation. The modal analysis proves that several nearly orthogonal modes can be generated at certain frequencies with orthogonal phase differences as well. The axial ratio (AR) corresponds to the modal analysis which proves the validity of the modal analysis. An axial ratio bandwidth from 3.1 to 6.2 GHz (66. 7%) is achieved within an S11 bandwidth of 2.6–11 GHz (123.5%). The proposed antenna is compact with stable radiation patterns, easy to design, and fabricate without inserting parasitic patches or inserting slots on the antenna.

A monopole broadband circularly polarized antenna with coupled disc and folded microstrip stub lines

A broadband circularly polarized (CP) printed monopole antenna which fed by coplanar waveguide (CPW) is proposed in the paper. The structure of the novel antenna includes a quarter circular disc radiating monopole, a coupled circular patch, and a bent L-shaped microstrip stub line. The L-shaped microstrip stub line is used to widen the impedance bandwidth and generate a horizontal component of the electromagnetic wave. The adoption of the asymmetric ground coplanar waveguide structure with the single-feed technology and the coupled circular patch, simultaneously achieve wide impedance bandwidth and wide axial ratio (AR) bandwidth. The structure parameters and the surface current of the designed antenna are analysed. The simulation and the measurement are conducted, showing good characterizations of the designed antenna. The 10-dB impedance bandwidth is 7.57 GHz, the fractional bandwidth from 6.05 to 13.62 GHz is 76.9%, the 3-dB axial ratio bandwidth is 3.01 GHz, and the fractional bandwidth from 6.05 to 9.06 GHz is 39.8%. The antenna can generate right/left hand circularly polarized waves in the direction of ± z axis. The designed antenna has wide applications in the fields of Internet of Things (IoT), broadband dual-CP communication systems and polarization diversity systems, wireless personal area network and other advanced communication systems.

Dual-band open-loop monopole (2 × 1) printed MIMO antenna for 4G and 5G applications

Abstract This paper presents a compact dual-band open-loop monopole MIMO antenna to serve 4G/5G applications. This antenna consists of two printed monopole antennas with very high isolation. Two enhancement techniques are utilized to improve the isolation between ports. Since each technique can provide high isolation of a single band, a combination of λ/4 slot and T-shape techniques are used to achieve high isolation of −19 dB and −35 dB at 2.4 GHz and 3.5 GHz, respectively. The proposed design has high efficiency, a low envelope correlation coefficient, and an acceptable level of realized gain (2.7 dBi and 2.2 dBi) at low and high bands. This design has been fabricated using low-profile printed circuit technology with a compact patch size of 50 × 25 mm2 based on an FR-4 substrate. Moreover, the simulation and measurement results are in good agreement.