Antenna For Mobile Phone Applications Research Articles

A Wideband Antenna with Circular and Rectangular Shaped Slots for Mobile Phone Applications

A wideband slot antenna for mobile phone applications is proposed. The antenna has two slots with open ends etched on the opposite edges of the ground plane. The main slot, of total length of 59 mm, is composed of a rectangle connected to a circle having radius of 5 mm. Another slot, having a rectangular shape with width of 2.8 mm and length of 26 mm, is employed to enhance the antenna bandwidth. The slots are fed by means of a rectangular monopole connected to a circular patch joined to a bent 50 Ω microstrip transmission line forming two right angles. To obtain a wideband impedance matching, the upper edge of the monopole and a part of the feeding line evolve along the top edge of the two slots. To reduce the antenna size, the upper part of the board above the slot (just 3 mm from the slot) is folded vertically to the ground plane. The measured bandwidth of the antenna is 0.698–1.10 GHz and 1.64–2.83 GHz covering LTE700/2300/2500, GSM850/900/1800/1900, and UMTS bands.

Small-Size Reconfigurable Loop Antenna for Mobile Phone Applications

A small-size reconfigurable loop antenna for mobile phone applications with a compact volume of $55 \times 5 \times 3$ mm3 is proposed. In addition to the traditional three loop antenna modes, namely, 0.5- $\lambda $ , 1- $\lambda $ , and 1.5- $\lambda $ modes, the proposed loop antenna also generates another 2- $\lambda $ mode. To cover more operating bands with such compact antenna volume, the reconfigurable technique is therefore applied by inserting an RF switch at the end of the proposed antenna to improve bandwidth at the low band. By combining the four working states of RF switch, the proposed antenna can cover GSM850/900, DCS1800, PCS1900, UMTS2100, and LTE2300/2500 bands with low specific absorption rate and high efficiencies.

Interaction Between Internal Antenna and External Antenna of Mobile Phone and Hand Effect

In this paper, we begin by presenting a multiband antenna for mobile phone applications operating in GSM, DCS, PCS, UMTS, Bluetooth, and LTE bands. The antenna platform includes the ground plane, the battery, the camera, and other paraphernalia that the mobile phone environment typically comprises. Results show that the platform has a significant effect on the performance of the antenna, both in terms of its bandwidth and the number of its resonance frequencies. In addition, metal rings, frequently used in a mobile phone for mechanical reasons, can also have a significant influence on the performance of the antenna in the phone. Equivalent circuits and current distributions have been derived with the objective of investigating the effects of the metal ring that embrace the mobile phone. We investigate ways in which we can modify the ring so as to restore the desired performance of the antenna, which has been previously designed to operate in the phone environment but without the presence of the ring. We show how we can control the resonances of the ring by using capacitance loading and lower its <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Q</i> by loading the ring resistively at a number of different strategic locations along the ring.

A penta-band folded antenna for mobile phone application

A penta-band folded antenna for mobile phone applications is presented.The antenna is comprised of two modified inverted-L monopole radiators with a short grounded transmission line for impedance matching and includes a ground plane printed on FR-4 substrate. The radiators are bonded onto a plastic carrier whose dimensions are 50 × 15 × 4 mm3. The antenna is designed and optimized to generate two separate bands, ranging from (i) 870 to 1010 MHz and (ii) 1710 to 2490 MHz with return loss for both better than 7.5 dB. Thus, the antenna covers five bands useful for mobile phone applications, namely, Global System for Mobile Communications/Digital Communication System/Personal Communication Services/Universal Mobile Telecommunications System/Bluetooth. The design strategy was such that the two separate widebands of interest can be controlled relatively independently. Design considerations for the constructed prototype are discussed. The effects of the ground plane, the mobile phone housing and the human hand on the return loss, and the efficiency of the proposed antenna are also investigated. It is found that the hand grip on the mobile phone has a significant effect on the performance of the antenna, especially its efficiency. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:34–40, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27274

Interview

Professor Youngje Sung from Kyonggi University in Korea talks about the research behind his Letter ‘Compact quad-band reconfigurable antenna for mobile phone applications’ on page 977.

Compact quad-band reconfigurable antenna for mobile phone applications

A compact reconfigurable antenna for quad-band (GSM/DCS/PCS/ WCDMA) mobile phone applications is proposed and experimentally investigated. By independently controlling the on/off states of a pin diode placed on a radiating element, the proposed antenna can be operated in the planar inverted-F antenna (PIFA) and loop modes, respectively. The measured results show that the 6 dB reflection coefficient bandwidths of the proposed antenna are 8.7% (880-960 MHz) and 14.3% (1950-2250 MHz) in the PIFA mode and 21.5% (1620- 2010 MHz) in the loop mode. By electrically selecting between the two modes, a variety of communication systems can be conveniently served through only one antenna.

Closely Mounted Compact Wideband Diversity Antenna for Mobile Phone Applications

Here a compact wideband diversity antenna covering the PCS/UMTS/WiMAX bands with high isolation and low enveloped correlation coefficient (ECC) is proposed. To widen the bandwidth, the proposed antenna uses a structure with a gap-coupled feed and an inductively shorted line that has capacitive compensation between the radiator and the ground plane. Also, a suspended line with a parasitic element is used to enhance the isolation between the two antennas.

A Compact Hepta-Band Loop-Inverted F Reconfigurable Antenna for Mobile Phone

A folded loop-inverted F reconfigurable antenna for mobile phone applications is designed and the obtained results are discussed in this communication. It is shown that loop antenna mode and an inverted F antenna (IFA) mode are controlled by only one p-i-n diodes with simple bias circuit. The impedance can be matched by adopting a matching bridge for both the loop and IFA modes. In a compact volume of 60 × 5 × 5 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> , the proposed antenna operates in hepta-band, including GSM850, GSM900, GPS, DCS, PCS, UMTS and WLAN, with the return loss lower than 6 dB. A prototype of the proposed antenna is fabricated, measured, and obtained results including return loss, efficiency and gain, are presented.

Two-inductor loaded loop antenna for mobile phones

A two-inductor loaded small loop antenna for mobile phone applications is presented. To optimise the loop antenna, positions and values of the two inductors in the loop antenna are changed by a simple genetic algorithm. The algorithm makes the antenna operate in GSM and DCS bands. Simulated results are compared with measured results and good agreement is reported.

A Miniatured WLAN/Wi-MAX Chip Antenna for Mobile Phone Applications

A compact WLAN/Wi-MAX chip antenna for mobile phone applications is pre- sented in this paper. Two chip antenna designs are proposed. One is for WLAN (2.4»2.48, 5.15»5.35, 5.725»5.85GHz) and Wi-MAX (3.4»3.7GHz). Its dimensions are 3mm £ 9mm £ 1.6mm. The other is for WLAN (2.4»2.48, 5.15»5.35, 5.725»5.85GHz)/Wi-MAX (2.5 » 2.7GHz). The dimensions are 3mm £ 11mm £ 1.6mm. The antenna conflguration of the two designs comprises two resonant branches. Not only the fundamental mode but also the second order resonance are utilized. Furthermore, the meander line structure is used to create two adja- cent resonant frequencies to achieve a tri-band operation. Measurements of the return loss and antenna patterns were performed. The measured result shows good agreement with simulated ones. The main advantage of the proposed chip antenna is that it doesn't require a guard region from other circuit components and is therefore attractive to mobile devices.

Co$_{2}$Z Hexaferrite T-DMB Antenna for Mobile Phone Applications

We fabricated 0.029 lambda miniaturized Co2Z hexaferrite terrestrial digital multimedia broadcasting (T-DMB) antenna. T-DMB antenna was fabricated by winding 12-turn Cu tape around the Co2Z rectangular block. Antenna was mounted on the ground substrate with connection of coaxial feeding line. Fabricated Co2Z antenna showed 196.2 MHz of center frequency, -6.55 dB of 3-D average gain and 22.13% of radiation efficiency at 195 MHz. Average gain of Co2Z antenna is found to be greater than -17.4 dB in the range of 174-216 MHz .

Very‐small‐size printed loop antenna for GSM/DCS/PCS/UMTS operation in the mobile phone

AbstractA very‐small‐size printed loop antenna for mobile phone application is proposed. The antenna has a loop strip of length 62 mm only, which is folded into an L‐shape and occupies a small area of 96.5 mm2 on the top no‐ground portion of the system circuit board of the mobile phone. By incorporating a simple matching circuit formed by a chip capacitor and a chip inductor, both in series, the loop antenna can generate three resonant modes (0.25‐, 0.5‐, and 1.0‐wavelength modes) at about 925, 1800, and 2200 MHz. The 0.25‐wavelength mode forms the antenna's lower band covering GSM operation, whereas the 0.5‐ and 1.0‐wavelength modes form the antenna's upper band covering DCS/PCS/UMTS operation. Quad‐band operation is hence obtained for the printed loop antenna, although it has a very small size. Details of the proposed antenna are presented. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 184–192, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24008

WWAN ceramic chip antenna for mobile phone application

AbstractA promising compact ceramic chip antenna capable of generating two wide operating bands at about 900 and 2000 MHz for covering GSM850/900/1800/1900/UMTS WWAN (wireless wide area network) operation is presented. The antenna comprises a ceramic chip base of high relative permittivity 40 and small volume 2.5 × 5 × 40 mm3 (0.5 cm3) and a simple metal pattern embedded therein. The metal pattern is of an asymmetric T‐shape with two different simple radiating arms; no meandering in the metal pattern is used, which is different from the meandered‐type metal pattern used in conventional chip antennas. Without meandering in the metal pattern, the possible large coupling between the adjacent portions in the metal pattern can be avoided. Large operating bandwidths are hence promising to be achieved. Also, without meandering in the metal pattern, the proposed chip antenna can still occupy a small volume for WWAN operation. The small volume allows it easy for the proposed antenna to incorporate the possible electronic elements such as the speaker and the lens of the embedded camera at the top portion of the system circuit board of the mobile phone to achieve a compact integration. Details of the proposed ceramic chip antenna are presented and studied. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 103–110, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24020

An internal wideband monopole antenna for UMTS/WLAN dual‐mode mobile phone

AbstractAn internal wideband metal‐plate monopole antenna for mobile phone applications is presented. The antenna is easily fabricated by bending a single metal plate and suitable to be embedded within the casing of a mobile phone as an internal antenna. Moreover, the antenna shows a wide operating bandwidth of about 5 GHz (about 1.8–6.7 GHz), making it easy to cover the UMTS band (1920–2170 MHz) and the 2.4–GHz (2400–2484 MHz) and the 5.2/5.8‐GHz (5150–5350/5725–5825 MHz) WLAN bands for mobile/WLAN dual‐mode operation of a mobile phone. The proposed antenna is studied in detail, and the experimental and simulation results of the constructed prototype are also presented. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1741–1744, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23546

Internal multiband surface‐mount monopole slot chip antenna for mobile phone application

AbstractA multiband monopole slot chip antenna surface‐mountable on the system circuit board of the mobile phone is presented. The antenna comprises two monopole slots of different lengths, which are folded and attached onto a foam base in the study. With a compact volume of 30 × 10 × 8 mm3 (2.4 cm3), the antenna can generate a lower band at about 900 MHz to cover GSM operation and a very wide upper band (bandwidth &gt;1 GHz) to cover DCS/PCS/UMTS operation and 2.4 GHz WLAN operation. It is also promising to use a ceramic base of relative permittivity 7.8 to replace the foam base of the antenna. In this case, the antenna volume can be reduced to be 24 × 10 × 8 mm3 (1.92 cm3) only, yet still capable of covering GSM/DCS/PCS/UMTS quad‐band operation. The proposed antenna is studied, and obtained results are presented and discussed. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1273–1279, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23342

Hexa‐band internal printed slot antenna for mobile phone application

AbstractA promising internal printed slot antenna for hexa‐band operation in the mobile phone is presented. The antenna comprises a C‐shaped slot and an open‐ended monopole slot, and both are integrated into a compact configuration to occupy a small area of 21 × 45 mm2 in the top portion of the system circuit board. The integrated C‐shaped slot and monopole slot are fed in series using a 50‐Ω microstrip feedline. The antenna can provide two wide operating bands centered at about 900 and 2200 MHz to cover the GSM850/900/DCS/PCS/UMTS mobile communication and the 2.4‐GHz WLAN operation. Good radiation performances of the proposed antenna over the operating bands are also obtained. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 35–38, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22981

Internal multiband printed folded slot antenna for mobile phone application

AbstractA novel printed folded slot antenna suitable for GSM/DCS/PCS/UMTS multiband operation in the mobile phone is presented. The proposed slot antenna has a planar configuration and is easy to fabricate by printing on the system circuit board of the mobile phone. The slot antenna has a length of 106 mm and is folded into a compact structure with its two slot ends facing toward each other. This configuration allows the antenna to occupy a small area of 21 × 45 mm2 centered on the top portion of the system ground plane. By feeding the slot antenna using a 50 Ω microstrip line printed along the centerline of the system ground plane, two wide bands (the half‐ and one‐wavelength modes) of the antenna can be generated, with the lower band covering GSM operation and the upper band covering DSC/PCS/UMTS operation. In addition, small excited surface currents in the system ground plane are observed, and the antenna's two operating bands are in general not sensitive to the ground‐plane length variations. These features are attractive for practical applications and different from those of the conventional internal mobile phone antennas. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1833–1837, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22602

Internal Compact Dual-Band Printed Loop Antenna for Mobile Phone Application

A novel dual-band printed loop antenna very promising for application in mobile phones as an internal antenna is presented. The antenna comprises an outer loop strip and an inner inverted-L strip connected to and enclosed by the outer loop strip. The antenna occupies a compact area of 15 times 50 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> only, yet generating three resonant modes to form two wide bands at about 900 and 1800 MHz for the Global System for Mobile Communication/Digital Communication System operation. Detailed design considerations of the three excited modes are described in the paper. When a shielding metal case is placed close to the antenna, small effects on the antenna's impedance matching are seen, allowing compact integration of the antenna with nearby conducting elements or electronic components. The antenna is also found to result in small excited surface current distributions on the system ground plane of the mobile phone. This behavior is expected to lead to reduced user's hand effects on the radiation efficiency of the antenna

Stubby monopole antenna for UMTS∕WLAN dual-mode mobile phone

A novel stubby monopole antenna for mobile phone applications is presented. The antenna is easily fabricated by bending a single metal plate. Further, the antenna shows a wide operating bandwidth of about 6 GHz (about 1.7−7.8 GHz), making it easy to cover the UMTS band and the 2.4/5.2/5.8 GHz WLAN bands for mobile/WLAN dual-mode operation of a mobile phone.

Design of tri‐band (EGSM/GPS/PCS) antenna with parasitic element for mobile‐phone application

AbstractThis paper proposed a novel design of tri‐band (EGSM/GPS/PCS) antenna for mobile phone application. The measured data and detailed antenna configure are available, too. The measured results show the design is successful and applicable. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1347–1350, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21651