Printed Monopole Antenna Research Articles

Broadband circularly polarized printed monopole antenna with protruded L‐shaped and inverted L‐shaped strips

AbstractA novel approach in the design of broadband circularly polarized antennas is presented in this article. The design uses a simple monopole structure with a triangular tapered feed. Right‐/left‐hand circular polarization (CP) is achieved by protruding L‐shaped strip and inverted L‐shaped strip along the left/right radiating edge of the monopole. It is proposed that the 3‐dB axial ratio bandwidth (AR‐BW) can be enhanced when the length of these strips is equal to λg/4 at the center frequency of their respective CP bands. This principle is verified by fabricating the prototype on 1 mm thick FR4 substrate occupying a compact area of 0.19 λ0 × 0.19 λ0. From the measurement results, it is observed that the overlapped bandwidth (S11 ≤ −10 dB and AR ≤ 3 dB) of the antenna is 129.04% (1.38–6.4 GHz) which covers all the major WLAN bands including the WiMAX. The proposed antenna has bi‐directional radiation characteristics with a broadside gain of 3.49 dBic in the CP band.

Circular antennaUWB microstrip line feeding planar modified

In this paper we have investigated compact printed semicircular disc monopole antenna, which is basically printed microstrip antenna with etched ground plane for UWB applications. In particular we have simulated very compact semicircular disc monopole antennas for UWB communication. Simple rectangular microstrip line is used for feeding the printed monopole antenna and its frequency bandwidth under -10dB return loss is ranging from 3GHz to 11.6 GHz. This compact printed monopole antenna works well for the whole UWB frequency band 3.1-10.6GHz.

Broadband Rectenna for Radio Frequency Energy Harvesting Application

A microstrip feed, double-sided printed monopole antenna is presented for radio frequency (RF) energy harvesting application. The antenna structure consists of a circular patch with a truncated ground plane. The ground plane consists of a rectangular notch right below the feed line, which helps to increase the bandwidth of the antenna. In addition, using a rectangular patch in the ground plane increases the effective area of the radiator due to loading effect, which leads to downshifting the lower cut-off frequency, and subsequently bandwidth enhancement. It is found that the ground patch provides the total antenna size reduction of 35.2% along with bandwidth and gain enhancement of 34.7% and 2.03 dBi at 0.9 GHz, respectively. The measured result shows that the proposed antenna offers an impedance bandwidth of 144.5% (0.89–5.53 GHz) with a peak gain of 4.3 dBi. Later, a rectenna system was designed and tested using the developed antenna for a wide range of frequencies. The rectenna system offers the maximum efficiency of 62.5% at 1.8 GHz at the load impedance of 5 kΩ.

Hexa‐band printed monopole antenna for wireless applications

AbstractIn this letter, a hexa‐band printed monopole antenna composed of various L‐shape radiating elements is presented for various wireless applications. The antenna is designed to fully cover the CDMA (870–890 MHz), GSM (900–1800 MHz), DCS (1710–1880 MHz), PCS (1900 MHz), LTE‐E/LTE‐D (2300–2800 MHz), and WLAN (2.45/5.8 GHz) frequency bands. The proposed antenna achieves a gain of 1.8 dB, 3.17 dB, 3.23 dB, and 5.82 dB at respective bands. Fabrication of the antenna is completed on Rogers RT‐5880 high frequency laminate with a finite ground plane having a rectangular slot on the other side of the substrate. The antenna is realized via standard printed circuit board (PCB) technology and its performance is validated by measurements in terms of s‐parameters and radiation characteristics.

High‐gain printed monopole arrays with low‐complexity corporate‐feed network

Printed monopole antennas fed by microstrip lines can provide a wide bandwidth and can be employed as terminal antennas in RF circuits. In the same perspective, the authors propose a novel planar array in which N + 1 parasitic monopoles, properly placed in a linear array where only N directly-fed monopoles are used, allow a broadside radiation and a gain value close to that of a standard printed array composed of 2N + 1 directly-fed elements. To verify the validity of the proposed design, prototype arrays for the S and C bands, composed of five- and nine-monopoles, are simulated, fabricated and tested. In addition, it is demonstrated that a flat metal sheet placed at 0.25 λ 0 from the array board can further increase the directivity of about 3 dB; as a result, the measured gain is ∼10 dB for the five-monopole array and 14 dB for the nine-monopole array. Owing to their large fractional bandwidth (30%) and high gain, these monopole arrays may work as external antennas for high-data-rate point-to-point transmissions or for C-band radar sensors.

A compact printed multistubs loaded resonator rectangular monopole antenna design for multiband wireless systems

In the present article, a compact triple-band multistubs loaded resonator printed monopole antenna is proposed. The antenna consists of a quarter wavelength two asymmetrical inverted L-shaped stubs to excite two resonant modes for 3.5/5.5 GHz bands and one integrated horizontally T-shaped stub with inverted long L-shaped stub to excite resonant mode for 2.5 GHz band. By loading these stub resonators along y-axis with distinct gaps, the antenna resonates at three frequencies 2.57/3.52/5.51 GHz covering the desired bands while keeping compact size of 24 × 30 mm2 (0.2 λ0 × 0.25 λ0). The proposed antenna is fabricated on Rogers RT/duroid 5880 substrate with thickness 0.79 mm and its performance experimentally verified. The measured results reveal that the antenna has the impedance bandwidths of about 210 MHz (2.50-2.71 GHz), 260 MHz (3.37-3.63 GHz), and 650 MHz (5.20-5.85 GHz), for 2.5/3.5/5.5 GHz WiMAX and 5.2/5.8 GHz WLAN band systems. The antenna provides omnidirectional radiation patterns and flat antenna gains over the three operating bands. In addition, the design approach and effects of multistubs resonator lengths on the operating bands are also examined and discussed in detail.

A Miniaturized 878 MHz Slotted Meander Line Monopole Antenna

<p>A slotted meander line printed monopole antenna for low frequency applications at 878 MHz is presented. The operating frequency of the conventional printed monopole antenna was greatly reduced by the presence of the slots and meander line which lead to the reduction of the antenna size. The size reduction up to 70% compared to the conventional reference antenna is achieved in this study. The antenna has a simple structure and small antenna size of 46.8 mm x 74 mm or 0.137𝝀<sub>0</sub> x 0.217𝝀<sub>0</sub>. The antenna has been fabricated on the low-cost FR4 substrate and measured to validate the simulation performances. Measured results display that the proposed antenna produces omnidirectional radiation pattern of impedance bandwidth of 48.83 MHz and the maximum gain of -1.18 dBi.</p>

Very Small-Size Uniplanar Printed Monopole Antenna for Dual-Band WLAN Laptop Computer Applications

This paper presents a very small-size uniplanar printed monopole antenna design with an overall size of only 8.7 mm $\times 5.4$ mm $\times 0.8$ mm. It is comprised of an open-ring structure and a hook-shaped radiating element that is extended within this open-ring structure. The proposed antenna can excite two resonance modes with broad 10-dB impedance bandwidths of 6.4% (2.35–2.51 GHz) and 19.5% (4.90–6 GHz), and this dual-band operation can cover the entire WLAN 2.4/5.2/5.8-GHz bands. Furthermore, a good gain of 3.34–5.38 dBi and desirable radiation efficiencies of 52%–87% were also measured across the two bands of interest.

Compact Tri-Band Notched Characteristics UWB Antenna for WiMAX, WLAN and X-Band Applications

Compact microstrip-fed printed monopole antenna with triple band-notched characteristics is suggested for ultra-wideband (UWB) applications. The antenna is constructed of a conventional rectangular microstrip patch antenna with partial ground plane and T-shaped strip employed in the ground plane as well as an inverted Ω- and L-shaped slots incorporated within the radiated element. The notched functions are created by the inverted Ω- and L-shaped slots, which are realized for WiMAX (from 2.69 to 4.5 GHz) and WLAN (from 5.49 to 6.37 GHz). The T-shaped parasitic strip generates the third notch for the X-band uplink satellite communication (from 8.15 to 9.61 GHz). The measured operating -10 dB bandwidth of the proposed antenna extends from 2.39 to more than 18 GHz except at the notched bands. The prototype antenna has a total area of 20×20×1.6 mm3. Electromagnetic (EM) simulations are carried out using 3D full-wave FEM-based simulator. EM simulation results are in good agreement with measurement results. The radiation pattern of the proposed antenna is nearly Omni-directional over the whole targeted band.

Modified rectangular shape patch antennas for ultra‐wide band and notch characteristics response

AbstractNovel designs of modified rectangular shape printed monopole antenna for Ultra wide band response are proposed, which gives bandwidth across 1GHz–10 GHz range. Further two variations of rectangular shape patches to realize tunable notch characteristics, are also presented. They yield tunable notch characteristics in two different frequency bands. Proposed antennas give broadside radiation pattern with peak gain of 2 dBi.

A new compact dual band printed monopole antenna using electromagnetic band gap structures

PurposeThe purpose of this paper is to present a new dual-band printed monopole antenna with a partial ground with two notched bands based on electromagnetic band gap (EBG) structures. A new type of EBG antenna with radiation patterns and antenna gains over the operating bands has been developed.Design/methodology/approachThe proposed antenna consists of a pair of EBG structures using a transmission line model. The proposed antenna is designed on an FR4 substrate with a thickness of 1 mm and permittivity (er) = 4.3.FindingsThe measured results show good dual-band operations with −10 dB impedance bandwidths of 9.1 and 36.2 per cent centered at 2.45 and 6.364 GHz, respectively, which covers the wireless local area network (WLAN) operating bands.Originality/valueA new type of EBG antenna with radiation patterns and antenna gains over the operating bands has been developed.

Simulation Study of a Small UHF Printed Monopole Antenna for Forward Scatter Radar Network

Simulation Study of a Small UHF Printed Monopole Antenna for Forward Scatter Radar Network

Miniaturization of Fractal Printed Monopole Antenna and the Equivalent Circuit for Low Frequency Bands

Miniaturization of Fractal Printed Monopole Antenna and the Equivalent Circuit for Low Frequency Bands

A Compact Dual Band-Notched Circular Ring Printed Monopole Antenna for Super wideband Applications

A Compact Dual Band-Notched Circular Ring Printed Monopole Antenna for Super wideband Applications

Ring Slotted Circularly Polarized U-Shaped Printed Monopole Antenna for Various Wireless Applications

In this communication, the design and performance of strip line feed U-shaped printed monopole antenna for Bluetooth/WI-Max/WLAN communications systems is reported. Proposed monopole antenna has an eight shaped slot on the patch and an eight shaped ring structure in the ground plane with metallic reflector just beneath the radiating element. The CST Microwave Studio 2014 is used for the simulation analysis of antennas while measurements are performed by applying Vector Network Analyzer. This radiating structure provides triple broad impedance bandwidths i.e. 265MHz (in 2.280 GHz to 2.545 GHz frequency range), 116 MHz (in 2.660 GHz to 2.776 GHz frequency range) and 2.12 GHz (in 3.83 GHz to 5.956 GHz frequency range), wider 3dB axial ratio bandwidth 1.33 GHz (in 4.69GHz to 6.02GHz range), flat gain (with maximum gain close to 5.56 (dBi) and good radiation patterns in the desired frequency range. This antenna may be a useful structure for 2.45GHz Bluetooth communication band as well as in WLAN and Wi-Max communications bands.

Parametric Study of Printed Monopole Antenna Bioinspired on the Inga Marginata Leaves for UWB Applications

A microstrip leaf-shaped printed monopole antenna bioinspired on the Inga marginata leaves is presented in this paper for UWB applications. A parametric study of the proposed antenna bioinspired geometry was conducted in order to verify their resonant properties. The antenna was designed with a rectangular slitted ground plane for impedance matching and fabricated on inexpensive glass fiber substrate and fed by a 50 Ω microstrip line. Numerical and experimental results were obtained. The results show an impedance bandwidth superior to 10.26 GHz, greater than the bandwidth considered UWB (7.5 GHz). Antenna dimensions were optimized with the computer program Ansys Designer® used to simulate the electromagnetic behavior of the antennas by the method of moments.

Very small planar broadband monopole antenna with hybrid trapezoidal–elliptical radiator

A compact and broadband printed monopole antenna (PMA) with a hybrid trapezoidal–elliptical radiator is proposed. An overlap region between the trapezoidal and elliptical patches is introduced to enhance the impedance bandwidth. Meanwhile, by etching two symmetrical quarter-elliptical slots on the ground plane and optimising the ellipticity ratio, further improvement in the impedance bandwidth is achieved. Measured results show that the antenna can cover the frequency range of 2.4–18.6 GHz (|S 11| < −10 dB) while its total size is only 25 × 25 × 1.2 mm3. In addition, omnidirectional radiation patterns, desirable gain, high radiation efficiency and nearly constant group delay are obtained. Compared with recent PMAs, the proposed antenna has a smaller size and wider bandwidth, simultaneously.

Compact Planar Ultrawideband Antennas with 3.5/5.2/5.8 GHz Triple Band-Notched Characteristics for Internet of Things Applications

Ultrawideband (UWB) antennas, as core devices in high-speed wireless communication, are widely applied to mobile handsets, wireless sensor networks, and Internet of Things (IoT). A compact printed monopole antenna for UWB applications with triple band-notched characteristics is proposed in this paper. The antenna has a very compact size of 10 × 16 mm2 and is composed of a square slotted radiation patch and a narrow rectangular ground plane on the back of the substrate. First, by etching a pair of inverted T-shaped slots at the bottom of the radiation patch, one notched band at 5–6 GHz for rejecting the Wireless Local Area Network (WLAN) is generated. Then, by cutting a comb-shaped slot on the top of the radiation patch, a second notched band for rejecting 3.5 GHz Worldwide Interoperability for Microwave Access (WiMAX) is obtained. Further, by cutting a pair of rectangular slots and a C-shaped slot as well as adding a pair of small square parasitic patches at the center of the radiating patch, two separate notched bands for rejecting 5.2 GHz lower WLAN and 5.8 GHz upper WLAN are realized, respectively. Additionally, by integrating the slotted radiation patch with the narrow rectangular ground plane, an enhanced impedance bandwidth can be achieved, especially at the higher band. The antenna consists of linear symmetrical sections only and is easy for fabrication and fine-tuning. The measured results show that the designed antenna provides a wide impedance bandwidth of 150% from 2.12 to 14.80 GHz for VSWR < 2, except for three notched bands of 3.36–4.16, 4.92–5.36, and 5.68–6.0 GHz. Additionally, the antenna exhibits nearly omnidirectional radiation characteristics, low gain at the stopbands, and flat group delay over the whole UWB except at the stopbands. Simulated and experimental results show that the proposed antenna can provide good frequency-domain and time-domain performances at desired UWB frequencies and be an attractive candidate for portable IoT applications.

CPW-Fed Wideband Circularly Polarized Printed Monopole Antenna With Open Loop and Asymmetric Ground Plane

A wideband circularly polarized (CP) printed monopole antenna with coplanar waveguide feeding is proposed. The antenna is composed of a rectangular monopole, an asymmetric ground plane, and a square-ring with an open gap at the bottom. By utilizing the asymmetric ground plane, CP radiation could be achieved at the upper band first. Then, a rectangular open loop is introduced to obtain wide-impedance bandwidth and broadband CP characteristic. The measured results demonstrate that the 10-dB impedance bandwidth reaches 96.5% (2.76 GHz, 1.48-4.24 GHz) and the 3-dB axial-ratio bandwidth is 63.3% (1.9 GHz, 2.05-3.95 GHz). In addition, parameter studies are performed, and surface current analysis is also given to show the operating mechanism of CP operation.

A Broadband Circularly Polarized Printed Monopole Antenna With Parasitic Strips

A novel printed monopole antenna is presented for circular polarization (CP) operation with broad axial-ratio (AR) bandwidth. The antenna is composed of a monopole, a ground plane, and two parasitic strips. By utilizing two spiral strips coupled by the monopole, broadband CP radiation is achieved. The measured results show the 10-dB impedance bandwidth is 2.75 GHz (1.75-4.5 GHz) and the antenna also has a 3-dB AR bandwidth of 64.7% (2.2 GHz, 2.3-4.5 GHz). The proposed antenna features simple structure and broad AR bandwidth, which is desirable for various wireless communication systems.