Circular Disc Monopole Research Articles

Cross shaped slot printed UWB monopole antenna with notch function

In this paper wehave investigated and proposed a printed modified circular disc Ultra-Wideband (UWB) monopole antenna with cross-shaped slot in radiating patch having a notch function. The proposed antenna covers the entire UWB band (i.e., 3.1 to 10.6 GHz) except frequency band of IEEE 802.11a (i.e., from 5.15---5.83 GHz). In particular we have simulated modified circular disk monopole antenna with cross-shaped slot, the notch frequency can be adjusted by the changing the position of the cross-shaped slot in the radiating patch. Here simple rectangular microstrip lines are used for feeding the printed monopole antennas. This UWB monopole antenna designed works well for the whole UWB frequency band 3.1---10.6 GHz from the HFSS simulation results.

Printed planar circular radiating patch ultra wideband antennas

In this paper we have investigated printed circular disc monopole antenna, which is basically printed microstrip antenna with etched ground plane for ultra-wideband (UWB) applications. In particular we have simulated circular disc monopole antenna with etched ground plane. Simple rectangular microstrip line is used for feeding the printed monopole antenna and which is having impedance of 50 Ω. This designed circular disc UWB monopole antenna works well for the whole UWB frequency band 3.1---10.6 GHz.

A universal methodology for designing a UWB diversity antenna

A universal methodology for designing a ultra-wideband (UWB) diversity antenna is presented in this paper. The main advantage of the methodology is that by using only a familiar symmetrical UWB antenna, a UWB diversity antenna with a compact size, wide impedance bandwidth and good isolation between two feeding ports can be designed conventionally. Another advantage of the methodology is that the distance between two radiators is almost equal to the distance between two feeding lines, thus a complicated structure to decouple the mutual interaction between two radiators is not necessary in the antenna design, and the configuration of the UWB diversity antenna is simple. As an example, a UWB diversity antenna with a compact size of 36 mm × 36 mm operating at a frequency range of 3.1–10.6 GHz designed by using a circular disc monopole UWB antenna is constructed, measured and analysed. The simulated and measured results show that across the UWB, the antenna can achieve a broad impedance bandwidth with good isolation of <−15 dB. The radiation patterns, gain and envelope correlation coefficient are also measured. Furthermore, to demonstrate the effectiveness of the methodology, another UWB diversity antenna designed by using another symmetrical UWB antenna which is a bevelled rectangular monopole UWB one is simulated.

Rectangular Ring Antenna Excited by Circular Disc Monopole for WiMAX System

This research presents a rectangular ring antenna excited by a circular disc monopole (CDM) mounted in front of a square reflector. The proposed antenna is designed to cover a frequency range of 2.300–5.825 GHz and thereby is suitable for WiMAX applications. Multiple parametric studies were carried out using the CST Microwave Studio simulation program. A prototype antenna was fabricated and experimented. The measurements were taken and compared with the simulation results, which indicates good agreement between both results. The prototype antenna produces an impedance bandwidth (|S11|&lt; −10 dB) that covers the WiMAX frequency range and a constant unidirectional radiation pattern (θ=0°and∅=90°). The minimum and maximum gains are 3.7 and 8.7 dBi, respectively. The proposed antenna is of compact size and has good unidirectional radiation performance. Thus, it is very suitable for a multitude of WiMAX applications.

Design of Monopole Antenna Based on Fractal Geometry

This paper presents a circular disc monopole antenna based on fractal geometry. The antenna is designed to be applied in UWB systems. So it is essential to ensure that the bandwidth of the antenna ranges from 3.1 GHz to 10.6 GHz, that is, IEEE 802.15.3a. However, the proposed antenna has achieved working in the required bandwidth. Compared to the antennas illustrated in most similar literatures, the proposed antenna has a much smaller size, which makes the antenna possible to be integrated with portable devices. Firstly, the antenna was designed through CST Microwave Studio. Then, the antenna was fabricated according to the simulated results. At last, the comparison between the simulated results and measured results was carried out which demonstrated good consistency.

Bandwidth Enhancement of Compact Monopole Antennas for Application in UWB Communication System

In this paper a microstrip transmission line fed compact monopole antenna for the wide-band (2.5 GHz - 11 GHz) communication system is designed and its performance is verified. In particular, we have simulated four types of wideband monopole antennas: rectangular, modified rectangular, circular and modified circular disk monopole antennas. Simple rectangular microstrip lines are used for feeding the monopole antennas. This compact monopole antenna designed works well for the whole UWB frequency band 3.1-10.6GHz from the IE3D simulation results. The compact antenna has the good performance including wideband impedance matching, reliable radiation pattern at all the frequencies. The novel antenna presented in this paper is expected to find application in future UWB system.

UWB meshed solar monopole antenna

A novel combination of a parametrically optimised UWB meshed circular disc monopole antenna with a polycrystalline silicon (poly-Si) solar cell is presented and discussed. The results indicate that the fabricated meshed solar monopole antenna operates across the frequency band 2.33–10.8 GHz with an average broadband gain of 4.1 dBi. It is demonstrated that by meshing the monopole pattern an adequate solar efficiency of 13.1% can be achieved.

Narrow Band and UWB Wearable Antennas: Design and Assessment of the Conformal Characteristics in Terms of Impedance Matching and Radiation Properties

In this paper the design of textile antennas for materials with three different substrate permittivity εr =3, 2.12, 2.22 are realized. Different textile substrates having different permittivity affect the antenna performance in various ways. Here, Microstrip Patch Antenna is designed for narrow band WBAN (Wearable Body Area Network) at the frequency level of 2.45GHz &amp; also a design of circular disc monopole textile antenna with the operating frequency of 2.5GHz to 5GHz for UWB (Ultra Wide Band) is realized. For all design, Dacron fabric, denim jeans fabric and thick fleece fabric are used as antenna substrates &amp; woven copper threads are used as the conductive part of the antenna patch. This paper demonstrates the effects of antenna bending at three different angles for both the antennas with denim jeans substrate. Here, resonance frequency fluctuations due to impedance matching as well as effects of radiation pattern deformation due to bending for different textile material substrates are focused. Several antennas have been tested on different substrates with acceptable performance. But this paper concentrates on textiles substrates rather than others. However here, with what extent the antenna will manage to give better performance with flexibility of textile material are mainly observed.

A CPW-FED PROPELLER SHAPED MONOPOLE ANTENNA WITH SUPER WIDEBAND CHARACTERISTICS

A super-wideband antenna based on a propeller shaped printed monopole with a CPW feed is presented in this paper. The enhanced bandwidth is obtained by modifying the disk of a conventional circular disk monopole to resemble a propeller. This design produces an extremely wide impedance bandwidth from 3 to 35GHz with an impedance bandwidth ratio of 11.6:1. The gain of the proposed antenna varies from 4dBi to 5.2dBi. The antenna has fairly stable radiation characteristics throughout its operating band. The developed prototype is fabricated and measured. Simulation and experimental results are in good agreement.

Embroidered wearable antenna for ultrawideband applications

AbstractAn electroconductive polyester yarn is used to fabricate an embroidered wearable monopole antenna for ultrawideband applications.Here, the structure of this embroidered antenna is a common coplanar waveguide‐fed circular disk monopole antenna. From the experimental results, a 10‐dB impedance bandwidth from 2.7 to 10.62 GHz is measured, while steady gains with near omnidirectional radiation patterns are exhibited within the bands of interest. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2597–2600, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27133

A UWB Bidirectional Rectangular Ring Antenna Fed by CDM with a Rod and Ridges for Constant Beam Direction

This paper presents an ultra-wideband (UWB) rectangular ring antenna excited by a circular disc monopole (CDM) with a conducting rod and two double ridges to radiate bidirectional pattern with constant beam direction along the entire UWB frequency range of 3.1–10.6 GHz. The conducting rod and double ridges at the upper wall of the ring are added to solve the tilted beam problem at the higher edge frequency whereas the double ridges at the lower wall are used to enhance the impedance bandwidth. The dimensions of the rectangular ring and the CDM are initially considered to achieve the bidirectional pattern with the suitable resonant frequencies and bandwidth. Then, the parameters of copper rod and two double ridges are determined by parametric study using CST Microwave Studio simulation software. The prototype antenna was fabricated, and the measured results show good agreement with the simulated ones. The obtained bandwidth of |S11|&lt;-10 dB can cover the UWB frequency range as well as the bidirectional beam radiation with constant beam direction (θ=0°,180° and ϕ=90°). The minimum and maximum measured gains are 3.1 dBi to 5.3 dBi, respectively. The proposed antenna possesses compact size with good radiation performance that can be a promising candidate for UWB applications.

Study of a novel U‐shaped monopole UWB antenna by transfer function and time domain characteristics

AbstractA novel U‐shaped monopole antenna suitable for ultrawideband (UWB) application is presented and investigated in this article. The antenna is developed from printed circular disc monopole antenna, and the current distribution evident that the proposed antenna has a similar current. Three steps in ground plane is designed and adjusted to obtain UWB impedance matching. Experimental results show that the proposed antenna meets the requirement of wide working bandwidth of 3.1–10.6 GHz with VSWR &lt; 2. Study of transfer function (magnitude of S21/group delay) and time domain characteristic (waveform/fidelity) indicate a good UWB application behavior for the antenna. The proposed antenna has a compact size, good radiation characteristics, ultra wide bandwidth, and good time‐domain behaviors to satisfy the requirement of the current wireless communications systems. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1532–1537, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26840

A planar circular disc monopole antenna with improved bandwidth

AbstractA planar circular disc monopole antenna with a broad bandwidth is presented, which is composed of a circular disc monopole patch and a rectangular ground plane, both printed on the two sides of a substrate respectively, and fed by a trapeziform microstrip feed line.The antenna has a wide bandwidth ranging from 1.89 to 19.26 GHz for return loss &lt; −10 dB, and exhibits a nearly omnidirectional radiation pattern. In this article, details of the proposed antenna design approach and measured results are presented and discussed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:593–595, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26595

Compact Disc Monopole Antennas for Current and Future Ultrawideband (UWB) Applications

Circular disc monopole antennas are investigated for current and future ultrawideband (UWB) applications. The studied antennas are compact and of small size (25 mm × 35 mm × 0.83 mm) with a 50-Ω feed line and offer a very simple geometry suitable for low cost fabrication and straightforward printed circuit board integration. More specifically, the impedance matching of the classic printed circular disc UWB monopole is improved by introducing transitions between the microstrip feed line and the printed disc. Two particular designs are examined using a dual and single microstrip transition. By using this simple antenna matching technique, respective impedance bandwidths (|Sn | <; -10 dB) from 2.5 to 11.7 GHz and 3.5 to 31.9 GHz are obtained. Results are also compared to a classic UWB monopole with no such matching network transitions. Measured and simulated reflection coefficient curves are provided along with beam patterns, gain and group delay values as a function of frequency. The transient behavior of the studied antennas is also examined in the time domain.

Multiband-integrated antenna/artificial magnetic conductor

An artificial magnetic conductor (AMC)-based multiband low-profile antenna for vehicle applications is designed, simulated and measured in this study. The AMC is a simple dual band structure, constructed on a 3.2 mm-thick FR-4 (e r =4.4) board, with the reflection phase and surface wave bandgaps in the 2.0 and 5.8 GHz ranges. A wideband printed circular disc monopole antenna uses this dual-band AMC as a ground plane resulting in a low-profile, multiband and platform-tolerant antenna system. The operating frequency bands covered are GPS (1.57542 GHz), DCS (1.710-1.880 GHz), PCS (1.850-1.990 GHz), UMTS (1.925-2.175 GHz), WLAN (2.4-2.485 GHz), WiFi (5.15-5.825 GHz) and V2X (5.76-5.84 GHz) using a -10 dB reflection coefficient criterion. It is demonstrated that the antenna gain increases significantly when the AMC is used over a large metal ground plane for the antenna.

UWB-MIMO ANTENNA WITH NOVEL STUB STRUCTURE

A compact printed and planar Multiple-Input Multiple- Output (MIMO) for Ultra Wideband (UWB) communications is presented. Two circular disc monopole antenna elements constitute the proposed UWB-MIMO antenna operating over the frequency band of 3.2{10.6GHz. The isolation between the antenna ports has been enhanced to the value of more than 15dB throughout the frequency band of interest. This enhancement is achieved by taking the advantage of an inverted-Y shaped stub that is being inserted on the ground plane of UWB-MIMO antenna. The insertion of the stub has also facilitated reduction of the size of the antenna, i.e., overall dimensions of the antenna are 40 £ 68mm 2 . The proposed antenna is investigated both numerically and experimentally.

On the design of wheel‐shaped fractal antenna

AbstractThis article presents the design of a wheel‐shaped wide band fractal antenna. This fractal antenna has been designed on substrate εr = 4.3 and thickness h = 1.53 mm. The new antenna has been fed with coplanar waveguide‐fed. The antenna exhibits the excellent ultrawide bandwidth from 0.95 to 4.495 GHz corresponding 130.21% at S11 &lt; −10 dB. The fractal antenna has been curved from the solid circular patch of 50 mm diameter. The first resonant frequency of this fractal antenna shifted to 1.15 GHz in comparison to 1.64 GHz first resonant frequency of circular disk monopole antenna. This indicates the size reduction of the antenna. The experimental radiation pattern of antenna is nearly omnidirectional. Such type of antenna can be useful for mobile and wireless communication. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:155–158, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25677

On the design of inscribed triangle non-concentric circular fractal antenna

This article presents the new ultra-wideband fractal antenna with CPW-fed.The fractal antenna has been fabricated on substrate εr = 4.3 mm and thickness h = 1.53 mm with 15-mm radius. This antenna inscribed triangles in non-concentric circles with varied radius offers the excellent bandwidth around 13.54 GHz (span from 1.335 to 14.88 GHz) corresponding to 167% impedance bandwidth at S11 < −10 dB. The first resonant frequency of fractal antenna shifted to 1.51 GHz by the application of fractal geometry in comparison to solid circular disc monopole first resonant frequency 2.215 GHz. This indicates the size reduction of the antenna. The experimental radiation patterns of the antenna are nearly omni directional. The proposed antenna is useful for mobile communication and UWB communication system. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2696–2699, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25555

Design and Measurements of Ultra-Wideband Antenna

This paper describes the design, realization and experimental measurements of an antenna element to operate at ultra-wideband (UWB) spectrum. The type of this antenna is a circular disk monopole (CDM), with two notches opposite to each other at two sides of the disk. The feed of the antenna is a coplanar waveguide (CPW). The effect of the presence of the notches is studied through simulations and tested experimentally.

Characterization and Comparison of GaAs/AlGaAs Uni-Traveling Carrier and Separated-Transport-Recombination Photodiode Based High-Power Sub-THz Photonic Transmitters

We describe in detail the characterization of two high-power photonic transmitters based on two different kinds of high-power photodiodes, one a GaAs/AlGaAs based uni-traveling-carrier photodiode (UTC-PD) and the other a separated- transport-recombination photodiode (STR-PD). The diodes operate under optical pulse excitation at the 800 nm wavelength. Both PDs have the same total depletion layer thickness (same theoretical RC-limited bandwidth) and are monolithically integrated with the same broadband micro-machined circular disk monopole antennas to radiate strong sub-THz pulses. However the STR-PD based transmitter exhibits very different dynamic and static performance from that of the UTC-PD based transmitter due to the existence of a low-temperature-grown GaAs (LTG-GaAs) based recombination center inside the active region, and the much thinner thickness of effective depletion layer. Under optical pulse excitation (~ 480 pJ/pulse), the STR-PD based transmitter exhibits a much lower maximum averaged output photocurrent (1.2 mA versus 0.3 mA) than that of the UTC-PD transmitter, although the radiated electrical pulse-width and maximum peak-power, which are measured by the same THz time-domain spectroscopic (TDS) system, of both devices are comparable. These results indicate that although the recombination center in the STR-PD degrades its DC responsivity, it effectively improves the high-speed and output power performance of the device and eliminates the DC component of the photocurrent, which should minimize device-heating problem during high-power operation. The radiated waveforms of both devices under intense optical pulse illumination also exhibit excellent linearity and strong bias dependent magnitude. This suggests their suitability for application as photonic emitters and possibly as a data modulator in sub-THz impulse-radio communication systems.