Circular Patch Antenna Research Articles

Ring monopole antenna for Tera-Hertz application

In this paper, a circular slot microstrip patch antenna is proposed for Tera-Hertz application. The entire structure is developed on a substrate having 4.4 and 0.02 as relative permittivity ∈ r and loss tangent 0.2on FR4 substrate. The total size of the proposed antenna is 40 × 40 μm2. The height of the substrate is 1.6 μm. The proposed antenna has four resonating bands from 2.36 THz to 3.20 THz with the bandwidth of 2.69 THz, 3.92 THz to 5.38 THz with the bandwidth of 4.79, 7.36 THz to 8.70 THz with the bandwidth of 7.95 THz, 12.86 THz to 14.35 THz with the bandwidth of 13.70 THz. The Computer simulation tool an electromagnetic software is used for simulating the entire projected antenna. The simulated results such as return loss, VSWR, surface current, radiation pattern, gain, and directivity are presented. The simulated results show that the presented antenna is the right choice for Tera-Hertz application.

A circular monopole patch antenna loaded with inverted L-shaped stub for GPS application

This article introduces a planar monopole patch antenna for global positioning system (GPS) application. Our design has a circular patch with a stub of inverted L-shape which is used as the radiating portion and partial ground. Our proposed design of the stub allows the antenna to operate at a frequency of 1.5 GHz. The circular monopole is fed by an offset feeding to have an impedance match of 50 ohms. The compact antenna has been designed and simulated on RT Duroid 6006 material with relative permittivity ( ) of 6.15 and 0.0019 as the loss tangent. Our antenna has a dimension of 65 × 55 × 2.54 mm3 . A gain of 1.23 dB is observed at the resonant frequency of 1.5 GHz and the antenna exhibits dipole like radiation pattern both in E and H-plane. The antenna has better impedance matching, good gain and steady characteristics of radiation pattern across the operating bandwidth. High frequency structure simulator (HFSS) v.13.0 is used to carry out all the simulations.

A Novel Graphene Conductive Ink Based Circular Patch Antenna for 2.4 GHz Application

Graphene conductive ink based microstrip line fed circular patch is presented in this paper. The main objective of this work is to replace copper with graphene which is an emerging promising material, in the field of patch antennas with conventional rigid substrates using a simple printing technique and to measure its performance. The prototyped screen printed graphene antenna is perfectly radiating and the return loss, VSWR and gain of the graphene antenna is found to be better than conventional copper antenna. Also, the bandwidth of the graphene antenna is 1.6 times greater than that of the conventional copper antenna on rigid substrate.

A low profile miniaturized circular microstrip patch antenna for dual-band application

AbstractA low profile Circular Microstrip Patch Antenna (CMPA) with radius 5 mm has been designed to generate two resonant frequency bands that can be used for WLAN 5.2 (5.15–5.25) GHz, Wi-Fi (5.725–5.850) GHz and Dedicated Short-Range Communications (DSRC) (5.85–5.925) GHz application bands. The designed antenna has been slitted with two slits and a stub has also been attached resulting in an additional resonant band alongside the primary resonant band. Also, primary resonant frequency shifted from 7.22 GHz to 5.87 GHz yielding about 18.7% antenna miniaturization. Frequency bands generated by the designed antenna are (5.15–5.25) GHz and (5.71–6.01) GHz having peak gain 2.3 and 4.9 dB with broadside radiation pattern. A square shape FR4 substrate having dimension 32 × 32 × 3.2 mm3 and very thin copper sheet for radiating patch and ground has been used in the proposed antenna, which can fulfill the requirement of smaller antenna with dual band application. Simulation software HFSS ver.13 has been used to design and analyze the proposed antenna. Very good matching has been obtained between simulated and measured results.

Beam switchable radiosonde receiver antennas

In this paper, radiosonde receiver antennas are investigated as one of the most important parts of meteorological variables sounding. The specifications of the antenna is studied for receiving radiosonde signals from all directions and from different distances. The Final structure of the proposed antennas is omnidirectional antennas, which have both gains higher than 6.5 dBi and circular polarization in specific directions. Based on the polarization analysis performed, it is recommended to divide the antenna into two parts, the upper antenna elements with circular polarization (CP) and the side antennas with linear polarization (LP). By analyzing the antenna radiation pattern, we show that it is necessary to employ multiple antenna elements to implement the side antenna. For the upper antenna, two structures, namely cross-dipole antenna, and circular polarization patch antenna, are proposed. As side antennas, the patch antenna, the 3D reflector antenna, and the printed Yagi-Uda antenna are investigated at 403 MHz. The effect of various upper antennas on the side antennas is also presented. The results show that the combination of each upper antenna with the side antenna can be selected for the ground station receiver antenna. Finally, the proposed 3D reflector antenna is employed as the receiver in the practical radiosonde test to evaluate its performance. The measured received signal level confirms the appropriate performance of the proposed antenna.

Stably Polarized Wideband Circular Microstrip Antenna Excited in TM12 Mode

One of the major drawbacks of the U-slotted wideband microstrip patch antennas, i.e., the polarization instability at the high-end frequencies, is addressed by utilizing the next broadside TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sub> mode in circular patch antennas. The proposed antenna is capable of generating stably polarized waves over a wide frequency range of ~45% (2.05-3.25 GHz), which is not the case with the reported literature on U-slotted wideband patch antennas. The antenna comprises the U-slot and appropriately positioned shorting vias to achieve the desired impedance and radiation characteristics. It is fed by an L-probe and loaded with four non-resonating arc slits to suppress the TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sub> mode's E-plane sidelobes, which are very prominent otherwise. The polarization stability of the antenna is demonstrated through the surface current distributions on the patch, radiation patterns, and the x- and y-polarized gain over the frequency range of interest.

DESIGN OF CIRCULAR MICROSTRIP PATCH ANTENNAWITH DEFECTED GROUND STRUCTURE FOR UWB APPLICATIONS

Inthis paper different type of circular microstrip patch antenna models for Ultra Wide Band applications are proposed. The details of the simulation and the related results are presented.The main aim is that to show how the antenna will vary its performance when we use the defected ground structure as well as when we implement slots on thepatch and to know whether it will satisfy the UWB conditions or not. Different models gives us different outputs. Based on those outputs we can make sure which antenna gives us more bandwidth and which is more suitable for ultrawide band applications. For all the models FR4 substrate with dimensions 56x55x1.6mm3 and having a relative permittivity of er=4.4 is used.Feko software has been used for the simulation for all the models.

High-Gain Circular Patch Antenna and Array With Introduction of Multiple Shorting Pins

This article proposes gain-enhanced circular patch antenna and array with introduction of multiple shorting pins. The antenna consists of a circular patch and several shorting pins. Equivalent inductance is brought to the patch after introducing shorting pins. Thus, resonance of the patch shifts at higher frequency. Compared to a conventional circular patch without any pins, radiation area of the proposed patch is enlarged given the same resonance frequency, hence leads to gain enhancement. The number of pins introduced to a circular patch can be set freely due to its symmetrical feature. Moreover, surface current is restricted within a small area around the center of the patch after introducing multiple pins, leading to more concentrated radiation. An equivalent circuit model is built for the proposed antenna. Layout and number optimization rules for introducing shorting pins are formulated. With these rules, gain of a circular patch can be maximized for the applications under certain size restrictions. A prototype operating at 5.8 GHz is designed and fabricated. Furthermore, a 2*2 array based on the gain-enhanced circular patch elements is implemented. In the measurements, high gain, high efficiency, and narrowed half-power beamwidth of the patch antenna and the array are observed.

L-Probe 원형 패치 안테나를 이용한 ISO 11452-2 근거리 내성 시험 모사에 대한 연구

ISO 11452-2 is a well-known standard that tests the electromagnetic immunity of a device under test(DUT) in an anechoic chamber. ISO 11452-2 needs a large antenna and high-power amplifier to provide a high electric field in the chamber. In this test setup, finding the root cause and debugging issues is not easy because of varied limitation conditions. In this paper, we suggest two L-probe-fed circular patch antennas that emit a high electric field(over 800 V/m in the radar pulse ranges) on DUTs in the near field. Because the DUT is located 50 mm away from the antenna, the power amplifier consumes a small amount of power for the same electric field in ISO 11452-2. The proposed procedure has the advantage of industry usefulness with fast, handy, and cost-effective radiated immunity debugging of the DUT without considering the environment required by ISO 11452-2 and certain types of monitoring equipment with high immunity.

Graphene Based Circular Shaped Micro Strip Patch Antenna Array for 2.45 GHz ISM Band Application

Graphene based circular microstrip patch antenna array is presented in this paper. First a single circular patch to resonate at 2.45 GHz is designed in HFSS, then 1 × 2 array and 1 × 4 array are developed in order to improve the gain. The designed patch and arrays are fabricated using copper and graphene and the antenna parameters are measured and compared. This research work mainly focuses on two things; one is to improve the gain by developing array and the other one is to develop graphene antenna array using a simple, low cost printing method. Both are achieved, as the gain is improved by ~ 5 dB for 1 × 4 array when compared to single patch and the graphene antenna is fabricated and tested for its performance and found to be working perfectly as antenna in ISM Band.

Tilted Circularly Polarized Beam Microstrip Antenna With Miniaturized Circular Sector Patch Under Wideband Dual-Mode Resonance

A design approach to miniaturized, dual-resonant microstrip circular sector patch antenna with tilted circularly polarized (CP) beam is proposed. As mathematically laid down at first, the range of an asymmetric multiresonant prototype dipole’s length should be set as the positive odd-integer multiples of one-quarter wavelength, such that the resonant frequency could be accordingly reduced by one-half to the symmetric case. In this way, an asymmetric circular sector patch radiator can then be employed to realize a unique tilted CP beam by simultaneously exciting two orthogonal, odd-order resonant modes via proper perturbations. As numerically and experimentally validated, dual-resonant microstrip antennas with compact patch, flared angles of 330°/270°, impedance bandwidth of 26.6%/35.8%, and tilted CP 3 dB axial ratio (AR) bandwidth of 7.3%/12.0% can be realized on single-layered, air substrate with a height no more than 0.07 wavelength. It is evidently verified that the proposed approach should be effective for reducing patch size, enhancing impedance bandwidth and realizing tilted CP beam without increasing antenna profile, inquiring multiple radiators or employing reactance compensation techniques.

Low-Profile Wideband Vertically Folded Slotted Circular Patch Array for Ka-Band Applications

A vertically folded slotted circular patch operating at the Ka -band is proposed in this communication. Fed by a low-profile microstrip feeding structure, the proposed circular patch resonates at its quasi-TM21 mode and exhibits a wide operational band of 23.5%, which is more superior than many reported millimeter-wave circular patch antennas. A full-corporate fed $2 \times 2$ linearly polarized (LP) subarray based on the proposed circular patch is designed without any additional substrate layer, which is further extended into a $4 \times 4$ LP array and a $4 \times 4$ circularly polarized (CP) sequential rotation array. Both the LP and CP arrays are fabricated and measured. A good agreement between the simulated and measured results has been observed, thus validating the proposed design techniques. With the enhanced performance, for example, wideband, low-profile, low cost, and compact size, the demonstrated array antennas can present promising candidates for some popular Ka -band applications, such as 5G millimeter-wave communications and satellite communications.

Long-Range Displacement Meters Based on Chipped Circular Patch Antenna.

This paper presents a passive wireless long-range displacement sensor that is based on the circular patch antenna, and the detecting range of the sensor can be customized. The sensor consists of a chipped circular antenna with two opened rectangular windows, a substrate, and a ground plate with a sloping channel. No bonding between the antenna and the ground plate allows for the chipped antenna to slide along the sloping channel. The channel will drive the current flow on the plate once the chip is activated, increasing the effective electrical length and, consequently, decreasing the resonant frequency of the circular antenna. The sensing mechanism equates the measuring displacement to the relative movement of the antenna with respect to the ground that achieves the measurement of long-range displacement and, thus, the proposed sensor can avoid stress damage to the antenna due to excessive deformation. Three different range sensors were simulated in the the Ansoft high frequency structure simulator (HFSS). The results show that the resonance frequency of the antenna has a linear relationship with the varying chute depth beneath the chip. Three sensors were fabricated, and the experimental results also validated that the sensitivity of the sensor can be adjusted.

Strain omnidirectional detection based on circular patch antenna

In this research, a circular patch antenna is proposed for omnidirectional measurement of strains. Firstly, the interaction between the circular patch antenna and the strain is analyzed according to the cavity theory in electromagnetic waves. The resonant frequency is determined by the size of the patch antenna. While a strain is applied, the dimension of the patch antenna changes slightly. Then, the linear relationship between the frequency shift and the strain is obtained. The strain sensor based on circular patch antenna is fabricated to measure the strain in different direction. A microwave wireless detection system is established to detect the magnitude and direction of the structural strain. The experimental result is in good agreement with the strain gauge. It shows that the circular patch antenna is able to detect the structural strain omnidirectional and wireless, which lays a foundation for the further engineering applications.

A Polarization-Reconfigurable Wideband High-Gain Antenna Using Liquid Metal Tuning

This article presents a polarization-reconfigurable wideband high-gain antenna based on liquid metal tuning. The antenna consists of a center-feed circular patch antenna with a C-shaped slot as the driven element. To broaden the bandwidth and improve the realized gain, a parasitic circular disc and 13 circular directors are employed. The direction of polarization can be tuned by changing the location of the liquid metal alloy contained in the tube. The relationship between the dimensions and the maximally achievable gain has been analyzed. The antenna has exhibited a -10 dB impedance bandwidth from 4.3 to 5.3 GHz (a fractional bandwidth of 21.2%). A 14.4 dBi gain is achieved at 5.3 GHz. The simulation and measurement results show good agreement with each other.

A Conformal Ultrawideband Antenna With Monopole-Like Radiation Patterns

A simple conformal ultrawideband (UWB) antenna with monopole-like radiation patterns is proposed in this communication. To achieve the wide bandwidth, two rings are arranged concentrically around the main annular-ring circular patch antenna, in which two rectangular slots are added. The antenna has monopole-like radiation patterns generated by combining four propagation modes of TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01</sub> , TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">02</sub> , TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">03</sub> , and TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">04</sub> throughout the operating bands. To enhance the flexibility and robustness, the proposed antenna is fabricated using conductive fabric embedded into polydimethylsiloxane (PDMS) polymer. To our knowledge, this is the first flexible UWB antenna with monopole-like radiation patterns reported in the open literature. The measured results show that the antenna achieves a 10 dB return loss bandwidth from 2.85 to 8.6 GHz. Monopole-like radiation patterns are maintained throughout the frequency band, agreeing well with simulated results. This has been validated through the measured mean realized gain (MRG) pattern from 2.85 to 8.6 GHz. The fabricated antenna was bent and tested at various curvatures to verify its conformability. To evaluate suitability for UWB communications, the system-fidelity factors of the antenna are investigated using full-wave analysis in CST Microwave Studio, in both flat and bent conditions, validating its potential for UWB pulse transmission.

Design and Analysis of Circular Monopole antenna for WLAN and WI-Max Application in S band

In today’s existence, the technology for communication is continuously growing. The agile achievement in ultra-broadband antennas in wireless communication is increased. A circular monopole microstrip patch antenna has been developed in this research paper. The parameters grandiose by antenna perfmonance are researched. The design is designed to achieve desired gain and bandwidth at 2.4 GHz frequency, with a defected ground system (DGS). This antenna design has been effectuated using FR-4 as the dielectric substrate with 4.3 as dielectric constant. In computer simulation technology (CST) the model monopole circular microstrip patch antenna is simulated and the results needed are achieved. The S11 parameter is obtained as -17.28 decibels which is below -10 decibel. The gain obtained at 2.4 GHz frequency is 1.730 decibel. Application in S band devices, including Wi-Max, WLAN, radio altimeter, cordless phones, wireless headphones etc., were built in this research article.

Fractal Antenna Based on Split Ring Resonators with Defected Ground Structure

In this paper presents the design of a circular microstrip fractal antenna (CMFA) loaded with parasitic edge-coupled (EC) split ring resonators (SRR) and defected ground structure (DGS). The basic resonant structure is a circular patch antenna designed at 3.2 GHz on FR4 substrate with relative permittivity 4.4, and 1.6 mm thickness. One iteration of circular patch and slots is employed to form it fractal and so as to attain multiband performance, the antenna is inset fed by a 50? microstrip line. Further the work is extended to demonstrate the effect of placing split ring resonator to particular position of substrate, improves the impedance matching leading to improved bandwidth. In addition L shaped defected ground structures are used to improve the antenna performance. . A comparison between fractal antenna with and without SRRs and DGS is made and the results verifies that a better gain improvement and return loss. The dimensions of the antenna are 45 mm x 45 mm and it can be used for ultra wide band (UWB) applications.

A Self-Nulling Single-Layer Dual-Mode Microstrip Patch Antenna for Grating Lobe Reduction

A single-layer, dual-mode microstrip patch antenna with self-nulling patterns is proposed. The antenna consists of a circular microstrip patch antenna, surrounded by a shorted concentric ring patch, exciting the TM11 and TM21 modes, respectively. Adaptive radiation patterns with self-scanning and nulling capabilities are realized by concomitantly exciting these two modes. To attain the mode purity, four symmetrical arc slits, inspired by the surface current distribution of the TM21 mode, as well as two horizontal slits are placed in the ring patch. For the miniaturization purpose, the circular patch is loaded by three vertical slits. A prototype of the proposed antenna is fabricated and tested. The measured results are in good agreement with the simulation results. To showcase the effectiveness of the proposed self-nulling dual-mode antenna, it is employed as an antenna element in a linear scanning array with element spacing greater than one-wavelength to reduce its unwanted grating lobes.

Wideband Differentially Fed Patch Antennas Under Dual High-Order Modes for Stable High Gain

Wideband differentially fed patch antennas under dual high-order modes for stable high gain are proposed in this communication. The working principle is verified on a differentially fed circular patch antenna operating in TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">31</sub> and TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12 </sub> modes at first. Two open slots are loaded to the patch's edge to reconstruct the current distribution of TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">31</sub> mode, thus substantially increasing the broadside radiation. An additional slot is introduced at the patch center to perturb the TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12 </sub> mode and reshape its current to be more in-phase, by which sidelobe radiation is dramatically reduced. With use of loading of slots and shorting pins, the two modes are allocated in resonant frequencies to make up an enhanced bandwidth of 13.4% and produce high gain up to 13.7 dBi, with the beamwidth and gain level nearly unchanged in band. Then, the proposed method is further developed on a rectangular patch antenna, where three cascaded slots and four shorting pins are loaded to perturb TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">21</sub> and TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">03</sub> modes, and reshape their current distributions. In a similar way, the broadside radiation of TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">21</sub> mode is enhanced and the sidelobe of TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">03 </sub> mode is suppressed. At last, the antenna obtains a bandwidth of 12.4% and stable realized gain as high as 14.0 dBi.