Printed Monopole Slot Antenna Research Articles

CPW-fed printed UWB antenna with open-loop inverted triangular-shaped slot for WLAN band filtering

A compact CPW-fed printed monopole slot antenna is presented for ultra-wideband (UWB) applications. The antenna comprises of a dome-shaped radiating element in which embedded is an open-loop inverted triangular-shaped slot (TSS). The antenna is fed through a coplanar waveguide to provide an ultra-wide impedance bandwidth of 8.95 GHz (2.58–11.53 GHz) which corresponds to a bandwidth ratio of 1:4.46 for VSWR <2. The antenna possesses a notch band functionality to filter out interfering C-band signals like wireless local-area network (WLAN). The notch band frequency is determined by physical parameters defining the TSS that allows fine control of the notch's location. The proposed antenna also possesses a flat gain response expect at the notched band and occupies a relatively small volume of 25 × 25 × 0.8 mm3 for ease of system integration.

Simple Printed WWAN Monopole Slot Antenna with Parasitic Shorted Strips for Slim Mobile Phone Application

ABSTRACTIn this article, a simple printed monopole slot antenna with two parasitic shorted strips (a longer parasitic shorted strip and a shorter parasitic shorted strip) for penta‐band wireless wide area network operation in the slim mobile phone is presented. The monopole slot has a length of 40 mm only and is disposed near the bottom edge of the system ground plane of the mobile phone with a small distance of 6.5 mm. By adding longer parasitic shorted strip connected to the bottom corner edge of the system ground plane, good excitation of the monopole slot antenna at its fundamental (quarter‐wavelength) mode and chassis dipole‐type mode of the system ground plane can be obtained. The shorter parasitic shorted strip contributes additional resonant mode to the antenna. The excited resonant modes form two wide operating bands to cover the GSM850/900 operation (824–960 MHz) and GSM1800/1900/WCDMA Band I operation (1710–2170 MHz), respectively. Details of the proposed antenna are presented. The specific absorption rate results for the antenna with the presence of the head and hand phantoms are also studied. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2835–2841, 2013

WWAN printed monopole slot antenna with a parallel-resonant slit for tablet computer application

The use of a parallel-resonant (PR) slit for dual-band bandwidth enhancement of a small-size printed monopole slot antenna to achieve the wireless wide area network operation in the tablet computer is demonstrated. The antenna is easy to fabricate by printing on a thin FR4 substrate of size 10 × 45 mm2. The PR slit, mainly configured as a spiral shape to occupy a small area of about 6.5 × 6.5 mm2 on the FR4 substrate, generates two parallel resonances at about 1.2 and 2.5 GHz to, respectively, result in dual-resonance excitation of the quarter-wavelength and half-wavelength modes of the monopole slot at about 0.9 and 1.9 GHz. In this case, two wide operating bands are obtained to, respectively, cover the 824–960 and 1710–2170 MHz bands. That is, with the dual-band bandwidth enhancement contributed by the PR slit, the proposed antenna can cover the GSM850/900/1800/1900/UMTS bands with a small planar size. Details of the proposed antenna are described in the article. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:40–45, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27273

Dual-band printed monopole slot antenna with combination of L-slot and ARM-slot for WLAN application

Antenna communication technologies were developing fast in recent research area, and these technologies demand high performance antenna to coop with the development. Wireless local area network (WLAN) application is famous term in antenna field nowadays, where this application allowed the users to communicate in long range without wired connection. WLAN demands an antenna with small size and volume, low in cost and weight, easy to design, and can perform efficiently at two distinct frequencies. In this article, the dual-band antenna working at 2.45 and 5.8 GHz was proposed. The proposed antenna consists of L-slots and arm's slot, where these slots greatly influenced the dual-band ability. The combination of 45° of bending angle at all antenna edges and slots can enable the proposed antenna to have good performances in term of return losses, bandwidth percentages, and larger half-power bandwidth (HPBW) values at both frequencies. The proposed antenna works efficiently at 2.45- and 5.8-GHz frequency bands when this antenna gives return loss values of −25.1718 and −28.6754 dB, correspondingly. This device can generate a broad forward beam that covered −62.1 to 62.1° HPBW with 36% bandwidth at 2.45 GHz, whereas at 5.8-GHz band, the HPBW for this antenna covered from −77.4 to 52.2° with 7.04% bandwidth. The proposed antenna suits to be used in WLAN's applications such as in Wi-Fi, Bluetooth, and access point application. The proposed antenna measurement values meet the IEEE 802.11 standard to make this antenna reliable. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2668-2673, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26305

Simple printed monopole slot antenna for penta-band wireless wide area network operation in the mobile handset

A simple printed monopole slot antenna for penta-band wireless wide area network operation (824–960/1710–2170 MHz) in the mobile handset is presented.The monopole slot has a length of 50 mm only and is embedded close to the bottom edge of the system ground plane of the handset with a small distance of 11 mm. By adding a small-size C-shaped strip connected orthogonal to the bottom edge of the system ground plane, good excitation of the monopole slot antenna at its fundamental (0.25 wavelength) and higher-order resonant modes can be obtained. The excited resonant modes form two wide operating bands to cover the GSM850/900 operation (824–960 MHz) and GSM1800/1900/UMTS operation (1710–2170 MHz). Detailed operating principle and radiation characteristics including the specific absorption rate results of the proposed monopole slot antenna are described. Measured results of the fabricated antenna are also presented. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1399–1404, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26017

Bandwidth enhancement of internal WWAN antenna using an inductively coupled plate in the small‐size mobile phone

AbstractBy adding a small inductively coupled plate of size 10 × 45 mm2 to the system ground plane of the mobile phone with a short length of 60 mm only, wide lower and upper bands of its internal WWAN antenna (a printed monopole slot antenna in this study) to respectively cover the GSM850/900 and GSM1800/1900/UMTS bands can be obtained. The coupled plate is connected and vertically oriented to the system ground plane through a 10‐nH chip inductor, which effectively causes the small coupled plate to resonate at about 925 MHz. A new resonant mode contributed by the coupled plate is hence provided to enhance the bandwidth of the antenna's lower band, which is quickly decreased with decreasing ground plane length of the mobile phone. With the coupled plate added to the ground plane of length 60 mm, the obtained lower‐band bandwidth is about the same as that of the internal WWAN antenna for the ground plane of length 105 mm and without the coupled plate. Further, the antenna's upper band for the short ground plane of length 60 mm can still have wide bandwidth for both the cases with and without the coupled plate. Detailed effects of the inductively coupled plate on the bandwidth enhancement of the internal WWAN antenna are analyzed. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1247–1253, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25196

Bandwidth enhancement of small‐size internal WWAN laptop computer antenna using a resonant open slot embedded in the ground plane

AbstractA new bandwidth‐enhancement method of using a resonant open slot embedded in the ground plane or supporting metal frame of the display panel for a small‐size internal wireless wide area network (WWAN) laptop computer antenna is presented.To demonstrate the results, a small‐size printed monopole slot antenna with a length of 50 mm only, which is about the smallest among the internal WWAN laptop computer antenna that have been reported, is applied in this study. For such a small‐size WWAN antenna, the impedance matching in the 900‐MHz band is usually very poor and hence the obtained antenna's lower band cannot cover the desired GSM850/900 operation. By embedding a resonant open slot in the ground plane, which does not increase the size of the internal WWAN antenna, a wideband resonant mode with good impedance matching at about 900 MHz contributed by the resonant open slot can be generated to cover the GSM850/900 operation. Further, a wide upper band for the antenna to cover the GSM1800/1900/UMTS operation can also be obtained. Details of the proposed bandwidth‐enhancement method are studied in this article. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1137–1142, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25148

Multiband Printed Monopole Slot Antenna for WWAN Operation in the Laptop Computer

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A multiband printed monopole slot antenna promising for operating as an internal antenna in the thin-profile laptop computer for wireless wide area network (WWAN) operation is presented. The proposed antenna is formed by three monopole slots operated at their quarter-wavelength modes and arranged in a compact planar configuration. A step-shaped microstrip feedline is applied to excite the three monopole slots at their respective optimal feeding position, and two wide operating bands at about 900 and 1900 MHz are obtained for the antenna to cover all the five operating bands of GSM850/900/1800/1900/UMTS for WWAN operation. The antenna is easily printed on a small-size FR4 substrate and shows a length of 60 mm only and a height of 12 mm when mounted at the top edge of the system ground plane or supporting metal frame of the laptop display. Details of the proposed antenna are presented and studied. </para>

Printed monopole slot antenna for penta‐band operation in the folder‐type mobile phone

AbstractA monopole slot antenna suitable for folder‐type mobile phone application is presented. The antenna is placed at the hinge position of the mobile phone and occupies a small area of 15 × 40 mm2 on the top portion of the main circuit board of the mobile phone. The antenna can generate two wide operating bands to cover GSM850/900/1800/1900/UMTS penta‐band operation for the mobile phone in either the open state (talk condition) or close state (standby condition), although the two states have different ground plane conditions for the antenna. This behavior is achieved by connecting the upper ground of the folder‐type mobile phone to its main ground on the main circuit board not at the hinge position but at about the center of the side edge of the main ground where the excited surface current distributions are small. This greatly reduces the effects of the different orientations of the upper ground to the main ground on the antenna performances in the open and close states. Good radiation characteristics of the antenna over the operating bands are also obtained. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2237–2242, 2008; Published online in Wiley InterScience (www.interscience.wiley.com).DOI 10.1002/mop.23636