Circular Slot Antenna Research Articles

A Circular Shape Arc Slot Ultra-Wideband Antenna for Biomedical Applications

In modern communication systems, ultra-wideband (UWB) technology has garnered substantial attention due to its superior attributes compared to traditional narrowband communication systems. Over the past decade, UWB technology has also found applications in microwave-based imaging systems. This study introduces a simple planar coplanar waveguide-fed circular shape arc slot antenna designed specifically for biomedicine and microwave medical imaging applications. The proposed design is implemented on a 1.6-mm-thick FR4 substrate with a relative permittivity of 4.4 and a loss tangent of 0.0009. The antenna has physical dimensions of 26 mm × 29 mm and achieves an impressive bandwidth of 16.6 GHz, spanning 2.4 to 19 GHz. It exhibits a peak gain of 2.5 dBi and consistent omnidirectional radiation characteristics. Thorough temporal analysis validates the antenna's performance within acceptable limits, which is further affirmed through practical fabrication and testing, demonstrating strong agreement with simulation results.

High-gain UWB elliptical and circular slotted antipodal Vivaldi antenna for through wall detection

High-gain UWB elliptical and circular slotted antipodal Vivaldi antenna for through wall detection

Three‐element ultrawideband MIMO antenna based on shared‐radiator structures with high efficiency and gain

AbstractThis letter presents a novel three‐port ultrawideband (UWB) multi‐input‐multi‐output (MIMO) antenna that covers the sub‐6 GHz (between 1.7 and 6 GHz) frequency band for wireless device applications. The proposed antenna consists of two parts: a dipole and two centrosymmetric slot antennas with shared structures. The radiating arm of the dipole can be reused as the large slot ground without increasing the size. The novel circular slot antenna etched on the radiator and circular microstrip feed line are designed to achieve wide impedance bandwidth. Meanwhile, four chamfers are loaded at the corners of the dipole to further optimize the impedance match in the whole frequency band. The physical dimension of the proposed three‐port MIMO antenna is 70 × 45 × 0.762 mm3. Experimental results validate that the reflection coefficient remains lower than −12 dB and the port isolation is better than 12 dB in the entire operational bandwidth without any decoupling network. The measured average peak gains are up to 5.6 dBi for all three ports, accompanied by a radiation efficiency of 90% across the frequency spectrum. With the advantages of simple design, high gain and high radiation efficiency, the proposed three‐element MIMO antenna design is well‐suited for implementation in UWB applications.

A Broadband SIW Cavity-backed Circular Arc-shaped Slot Antenna for Millimeter-wave Applications

A Broadband SIW Cavity-backed Circular Arc-shaped Slot Antenna for Millimeter-wave Applications

Design of ultra wideband circular slot antenna for emergency communication applications

In this article, a compact ultra wideband circular slot antenna (CSA) is proposed for emergency communication applications. The circular shaped radiating structure is constructed on the top of the substrate. Double stub matching with microstrip feeding techniques is used for impedance matching. The slot loading technique is used to enhance the bandwidth of the antenna. The flexible RT/duroid 5880 dielectric material with permittivity of 2.2 is used for fabricating the proposed antenna. The performance analysis of the antenna has been carried out by using High Frequency Structure Simulator (HFSS) software. The measurement results show that the proposed circular slot antenna achieves a wider bandwidth of 4.65 GHz and maximum gain of 12 dB. The proposed antenna yields Specific Absorption Rate (SAR) of 1.3 W/kg which is suitable for wearable applications.

BANDWIDTH AND GAIN ENHANCEMENT OF CUP SHAPED UWB MICROSTRIP PATCH ANTENNA WITH DEFECTIVE GROUND PLANE FOR SUB-6 GHZ 5G APPLICATIONS

This paper presents the design of slotted ground plane and a circular ring slotted microstrip patch antenna for new radio (NR) band, sub-6 GHz, WLAN and Licensed Assisted Access (LAA) 5G applications. The design consists of cup -shaped microstrip patch antenna with a defective ground structure (DGS). The circular ring slot at the top of the patch and the modified rectangular slots at the bottom are helpful to improve the performance of the antenna, thereby increase the efficiency, bandwidth, gain and improved s-parameters. The proposed antenna is designed on FR4-epoxy substrate and inset feeding technique. The design and simulation of my proposed work are done using HFSS (ANSYS-Electronics suite 19.2×64 version). The antenna has a bandwidth of 2.56 GHz with maximum gain of 2.27 dB. The antenna operates for the bandwidth from 4.04GHz to 6.6 GHz which covers NR-New Radio band (3.4-4.2 GHz), Sub 6 GHz 5G band (n-79) (4.44-5.0 GHz), WLAN (5.15 - 5.35 GHz) and Licensed Assisted Access (LAA) band.

Wideband and low profile multipolarization reconfigurable antenna based on metasurface

AbstractIn this letter, a wideband and low‐profile multipolarization reconfigurable antenna based on metasurface (MTS) is proposed. The antenna mainly contains two parts, an upper layer of MTS and a bottom layer of circular slot antenna. The MTS acts as a polarization controller, by mechanically rotating the MTS layer at a proper angle while keeping the circular slot antenna remain stationary, the polarization mode of the antenna can be switched to linear polarization (LP), left‐hand circular polarization (LHCP), and right‐hand circular polarization (RHCP). The experimented −10 dB impedance bandwidth of 37.8% and 54% for LP and circular polarization (CP) modes, respectively. The measured overlapped 3‐dB AR bandwidth is 22.2% for both CP modes, covering from 3.2 to 4 GHz. Moreover, the measured peak gain of the presented antenna reaches 9 dBi and 8 dBic for LP and CP modes, with a lower profile of 0.05 λ0.

Compact bowtie-shaped microstrip patch antennas with low cross-polarization and wideband harmonic suppression

A compact microstrip-fed bowtie-shaped circular ring slot antenna with a fundamental resonant frequency at 5.5 GHz for WLAN standards is initially studied. By introducing two bilateral triangles (BLT) slits symmetrically on either side of the radiator with a defected ground structure (DGS), wideband harmonic suppression (HMS) has been achieved. To get the dual-band i.e., lower band at 5.5 GHz and the upper band at 17.41 GHz for direct broadcast services (DBS) transmission satellite communication applications and additional suppress the harmonics excited by the insert-fed cut, a single inverted U-shaped slot (DGS) is integrated into the bowtie-shaped patch. Bowtie-shaped single-band patch (BSBP) antenna measured impedance bandwidth (IBW) from 5.218–6.225 GHz (17.6%) and insert-fed bowtie-shaped dual-band monopole (IBDBM) antenna measured IBW from 5.254–6.168 GHz (16.61%) for the lower band and from 17.213–17.856 GHz (3.66%) for the upper band, a wideband HMS up to 3.17 f0 (f0= fundamental resonant frequency) characteristics are achieved in both cases. The proposed antennas have a wideband HMS, compact size, and a significant reduction in cross-polarization levels in E-plane radiation patterns. The design parameters are also predicted using a machine learning regression technique built on an artificial neural network and convolutional neural network algorithm.

Circular slot antenna for triband application

We recommend a circular monopole antenna (CMPA) with a central feed to operate in three bands. The antenna is circular and has an 8cm diameter. The suggested antennas' resonance frequency ranges are 2.43 GHz, 5.24 GHz, and 9.61 GHz. The planned CMPA is made up of two circle-shaped slots cut into the radiating patch. The whole structure is supplied via a microstrip feed line and analysed using CST Studio's electromagnetic simulator, which is based on finite integral technique (FIT). To check the structure, the return loss, radiation pattern, voltage standing wave ratio (VSWR), and gain are all examined. The structure's ideal dimensions are determined using a parametric study of three factors: feed position, feed breadth, and ground size. The proposed CMPA is capable of operating in several bands and has good matching impedance in all of them.

2.5 GHz to 3.5 GHz fractal metasurface microstrip antenna design for high bandwidth wireless applications

In this paper, the microstrip slot antenna is designed for a wireless application with fractal structure having 2.5 - 3.5 GHz coverage and 30% bandwidth. The circular slot antenna with seven triangular slots is considered and six single rings are added to the antenna. As a last step, the enhancement of the matching is produced by a disk located the central part of the slot. The fractal model improves the bandwidth, modifies the antenna matching and controls the current distribution in such a way that it is used in the S (short) band in our case for WiMAX technology, which allows wireless transmission of voice, data and video in areas of up to 48 km radius. It was projected as a wireless alternative to ADSL and cable broadband access, and a way to connect Wi-Fi nodes in a metropolitan area network. The antenna gain is about 19.37 dB with a compact size of 60 × 60 mm2. The metasurface structure helps us to improve the bandwidth. The antenna was simulated with Ansoft Designer V.3.5. The antenna is designed in FR4 as the most suitable material as well as being low cost and accessible. It is proved that the fractal shape is used to improve the bandwidth. The result of combining the metasurface with the antenna can be considered to improve the bandwidth

Design of Wideband Circular-Slot Antenna for Harvesting RF Energy

The design of a wideband circular-slot antenna for RF signal harvesting is reported in this work. The proposed design frequency range accommodates the leading contributors to the available RF signals accessible by the RFEH node. These widely utilized frequency bands comprise GSM1800, UMTS2100, Wi-Fi2.450, and LTE2600. The antenna geometry comprises circular-ring radiating component filled with two orbital circular and rectangular slots. At the bottom plane, a pair of rectangular and semirectangular-circle slits are integrated. The antenna presented is designed on a double layer of 1.6 mm high FR-4 substrate. The source antenna achieved a simulated and measured impedance bandwidth (BW) of 1.510 and 1.590 GHz, amounting to 68% and 73% fractional BW (FBW), covering -10 dB reflection coefficient (|S11|) between 1.640 to 3.150 GHz and 1.550 to 3.140 GHz, in that order. The wideband circular-slot source antenna realized a maximum measured gain of 1.88, 2.13, 2.81, 3.22, and 4.32 dBi for 1.800, 2.100, 2.450, 2.650, and 3.20 GHz, respectively. The proposed design dimension on the printed board is 0.61 λ g × 0.70 λ g . The improved antenna gain is obtained from a circular parasitic patch coupled to the defected ground structure (DGS) for better RF energy harvesting in an ambient environment.

Parasitic Element Based Frequency Reconfigurable Antenna with Dual Wideband Characteristics for Wireless Applications

A Microstrip Frequency Reconfigurable circular patch slot antenna for switchable Bluetooth, WiMAX, WLAN, and satellite communication applications is analyzed and presented in this work. The optimized overall size of 47 mm x40 mmx1.6 mm is utilized in the design, and which can cover wide range of frequencies below 10 GHz. In the initial phase, different monopole antennas are designed with various shapes of same size and later parasitic patch elements has been added to those monopole antennas. The circular monopole driven element and parasitic element are connected with a PIN diode, and which reinforced in achieving frequency reconfigurability. The proposed antenna is resonating at various frequencies of 2.4 GHz, 4 GHz, and 8.4 GHz when the diode in ON condition and resonating at 3 GHz, 5.4 GHz, and 8.4 GHz when the diode is in OFF condition. The performance of the designed antenna prototype is scaled and differentiated with the results of simulation and found good matching with respect to performance characteristics.

FSS superstrate loaded SIW circular cavity-backed cross-shaped slot antenna for wireless applications

In this paper, a low profile circular-shaped cavity-backed substrate integrated waveguide (SIW) antenna is designed and fabricated to operate at 5.38 GHz frequency in the U-NII-2B band in the dominant TM010 mode. A narrow cross-shaped slot is inserted in the ground plane of the parent antenna for radiation purposes. The antenna produces a gain of 4.7 dBi with an impedance bandwidth extending from 5.36–5.42 GHz. The gain of the antenna is augmented to 7.1 dBi through the use of a multi-layered cascaded frequency selective surface (FSS) as a superstrate. Arlon substrate materials are used to fabricate the antenna and frequency selective surface respectively. Parametric studies have been carried out in terms of return loss, antenna gain, and spacing between the antenna and FSS layer to obtain the best antenna results. All the simulation results have been carried out using HFSS v19.0. Both the simulated and the experimentally measured results show alike behavior.

60-GHz Wideband L-Probe Circular Slotted E-Shaped Patch Antenna Array

In this study, a 60-GHz wideband L-probe circular slotted E-shaped patch antenna array was presented. The novelty of this study can be summarized as follows: 1) An E-shaped patch was added to the L-probe to further expand the bandwidth of the existing L-probe patch. 2) The E-shaped slot was modified to a circular slot to improve the overall performance, including the radiation pattern, S₁₁, and cross-polarization of the original E-shaped patch antenna element. When compared to the original L-probe patch, the bandwidth was improved from 9.4% to 24.8% for the proposed antenna element. Furthermore, when compared with the triangular-shaped and rectangular-shaped slots, the cross-polarization level is improved by 3.5 dB and 2.5 dB, respectively. The proposed antenna was designed as a 2x2 array structure, and the size of the antenna array corresponded to 6.4 mm×6.4 mm×0.375 mm. The measured results of the proposed antenna array revealed 11.42 dBi peak gain, 25.8% fractional 3-dB gain bandwidth, and 44.7% -8 dB S₁₁ bandwidth.

DESIGN OF CIRCULAR SLOTTED RECTANGULAR MICROSTRIP PATCH ANTENNA WITH DUAL-RESONANCE FOR WLAN/WIMAX APPLICATIONS

In this work, a design for enhancing bandwidth of a dual-resonant circular slotted patch antenna for 2.4-3.5 GHz WLAN/WiMAX applications is proposed and tested. The designed antenna is a modified form of the rectangular patch antenna consisting of three identical circular slots in antenna surface and it printed on an FR-4 substrate. This antenna has two different operating frequencies, with center frequencies of 2.592 and 3.338 GHz. Classical microstrip antennas yield a maximum bandwidth of about 8%. By incorporating slots in antenna, the bandwidth of the antenna is improved. The fractional bandwidth at 2.592 GHz is 50.9% and at 3.358 GHz is 39.5%. The proposed antenna is simulated, fabricated and tested. Measured results showed good agreement with the simulated results. The gain of the antenna is 2.169 dB at 2.59 GHz and 2.175 dB at 3.338 GHz.

A simple and compact broadband circularly polarized circular slot antenna for WLAN/WiMAX/DBS applications

Abstract A simple and compact circularly polarized broadband circular slot antenna is proposed for WLAN/WiMAX/DBS applications. The main objective of this work is to design a microstrip line fed broadband circularly polarized antenna that is achieved by introducing an asymmetric perturbation over the circular slot onto the ground plane. A broad axial ratio bandwidth is achieved by using a small circular segment cut into the circular slotted ground and by adding a short stub on the feedline. To achieve a broad impedance bandwidth, a horizontal strip onto the slotted ground is placed just above the feed line on the opposite side. The proposed antenna is fabricated with an overall dimension of 20 × 20 × 1.6 mm3 (0.34λ o × 0.34λ o × 0.03λ o, where λ o represents the free-space wavelength at the center operating frequency). It is found that the impedance bandwidth of 75.82% ranges from 3.21 to 7.13 GHz and the 3 dB axial ratio (AR) bandwidth reaches 54.27% from 3.8 to 6.6 GHz. Throughout this paper, the improvement and validation process of the proposed antenna outcomes to accomplish desired characteristics are discussed.

CSRR-Loaded Crescent Slot Circular Antenna for WLAN/Wi-Fi Application

The Complementary Split-Ring Resonator (CSRR)-loaded crescent slot circular antenna is presented in this paper. The proposed antenna is resonating at 2.4[Formula: see text]GHz with the gain of 2.38[Formula: see text]dB. The antenna is designed for a predefined shape, which has a crescent slot, star-shaped small slots and spline split on a circle. The CSRR is carved on the ground surface of the antenna to acquire 2.4[Formula: see text]GHz and eliminates the multiple resonances created by various slots. The CSRR provides the miniaturization by shifting the resonance from 2.59[Formula: see text]GHz to 2.4[Formula: see text]GHz. The measured, [Formula: see text]6[Formula: see text]dB impedance bandwidth of the antenna is 11.25%. The antenna is fabricated using an FR4 ([Formula: see text]) substrate. The proposed crescent slot circular antenna is simulated using Ansys HFSS 17.0.

Circular Slotted Antenna with CPW feed for GSM and UWB Applications

Background & Objective: The circular slotted monopole microstrip antenna with Coplanar Waveguide (CPW) feed for unified GSM and Ultra-Wideband (UWB) applications have been presented in this article. Circular shaped slots have been embedded in the radiating patch. Less surface area has been found due to slots etching and the overall antenna size is reduced by 45%. Result: The proposed antenna demonstrates a double band operation wrapping 883.6-1206 MHz (GSM band) and 2.75-18.30 GHz (UWB, X, and Ku) frequency band with VSWR of less than 2 and fractional B. W. of 30.8 % and 147% respectively. The pattern of radiation presented by the antenna is nearly omnidirectional in H-plane and directional in E-plane within the GSM and UWB band. Conclusion: There is a variety of applications nowadays using these UWB antennas such as modern civil and military applications, wireless and radar communications, etc. Measured results are presented to validate the proposed antenna structure, which shows that the proposed designed antenna structure has a stable radiation pattern both at the GSM and UWB band ranges.

Log-periodic enactment of a novel patch with square DGS for Ku-band applications

A novel Log periodic patch with a circular slot antenna has been presented here, the perturbation of the shape of the antenna has been done by combining a triangular shape with a semicircular shape. The antenna proposed here is with a DGS structure on its ground plane and its effects on bandwidth and gain enhancement of the antenna are analyzed. The substrate of FR-epoxy material with length, breadth and height 170 mm, 50 mm and 1.6 mm, respectively is taken for implementation of the antenna on it. This proposed antenna operates at 12 GHz to 18 GHz which includes Ku-band with return loss below-10 dB. The parameters of antenna like S-parameters, antenna gain, directivity, VSWR, surface current distribution and radiation efficiency are determined one by one to ascertain its better performance. The simulation as well as the measurement results are comparatively analyzed.

Compact Circular Slot Antenna Array Devoted to Direction Finding

We present a circular array of diversely polarized slot elements devoted to a portable direction-finding system in the UHF 868 MHz band. The detailed structure is presented as a combination of two printed circuits boards (PCBs) (FR4 substrate) holding the radiating slots and strip feeds located inside a metallic box housing. Experimental validations in terms of scattering parameters and embedded element patterns are presented. A numerical experiment is performed regarding DoA estimation, while including all the effects of mutual coupling. The performance of the proposed array is compared with that of a patch array. Good resolution is observed despite the small size of the array.