Shih-Huang Yeh

Dual-band planar inverted F antenna for GSM/DCS mobile phones

A compact dual-band planar inverted F antenna suitable for the application as a global system for mobile communication/digital communication system (GSM/DCS) dual-band mobile phone internal antenna is proposed and implemented. The proposed antenna has three resonant elements, two meandered metallic strips of slightly different lengths and one nearly-rectangular patch, which are printed on a supporting FR4 substrate and arranged in a compact configuration. These three resonant elements share a common shorting pin, and for the GSM (890-960 MHz) operation, the proposed antenna is operated with the two meandered strips both resonated as a quarter-wavelength structure, leading to a wide bandwidth formed by two resonant modes. For the upper band of the proposed antenna, three resonant modes are generated, two from the second higher-order modes of the two meandered strips and one from the nearly-rectangular patch, leading to a wide bandwidth covering the DCS band (1710-1880 MHz). The antenna design and experimental results are presented.

Internal shorted patch antenna for a UMTS folder-type mobile phone

A novel design of feeding and short-circuiting an internal patch antenna for mobile phones is presented. The patch antenna comprises a simple rectangular patch that is fed through and short-circuited to a small ground plane (denoted as antenna ground here) which protrudes from the main or bottom ground of a folder-type mobile phone. With the presence of the small antenna ground, which can function as a shielding wall, the proposed antenna can be placed in close proximity to the RF shielding metal box in the mobile phone, with very small effects on the antenna performances. A design example of the proposed antenna for Universal Mobile Telecommunication System (UMTS) (1920/spl sim/2170MHz) operation is demonstrated. Experimental and simulated results are presented.

A wide-band monopolar plate-patch antenna

A new design of a monopolar plate-patch antenna is proposed and experimentally studied. The proposed antenna is a planar rectangular monopole top-loaded with a shorted square or circular patch, which is shorted to the antenna ground by two ground plates placed symmetrically on each side of the planar monopole. Prototypes have been constructed and experimental results show, that with an antenna height less than 10% of the free-space wavelength of the center operating frequency, the proposed antenna can have a monopole radiation pattern with an impedance bandwidth larger than three times that of a corresponding monopolar wire-patch antenna.

EMC internal patch antenna for UMTS operation in a mobile device

A novel patch antenna suitable to be applied in a mobile device as an internal antenna having an electromagnetic compatibility (EMC) property with nearby conducting elements is presented. The antenna is easily fabricated from a single metal plate and mainly comprises a top patch and an inverted-L vertical ground wall. Due to the presence of the inverted-L ground wall, which is perpendicular to the system ground plane of the mobile device, the possible fringing EM fields in the surrounding region of the antenna are suppressed. In this case possible coupling between the antenna and the nearby conducting elements is expected to be small, and thus degrading effects on the performance of the antenna are eliminated. A design example of the proposed antenna for Universal Mobile Telecommunication System (UMTS) 1920-2170 MHz operation in a mobile device is demonstrated and discussed.

Dual-band F-shaped monopole antenna for 2.4/5.2 GHz WLAN application

Antennas occupying a small volume of the system are very attractive for wireless local area network (WLAN) or Bluetooth applications. To further reduce the antenna volume and decrease the fabrication cost, the WLAN antenna using an inverted-F strip integrated on the circuit board of a communication device has been demonstrated previously. However, the antenna is capable of single-band operation only. A novel dual-band F-shaped monopole antenna, which can easily be integrated on a circuit board, is proposed. The antenna comprises a vertical metal line and two (one upper and one lower) horizontal metal lines of different lengths, which are used for tuning the antennas first two resonant frequencies to achieve dual-band operation in the 2.4 GHz (2.4-2.484 GHz) and 5.2 GHz (5.15-5.35 GHz) bands for WLAN applications. The proposed antenna printed and integrated on a small region of a microwave substrate has a compact size of 10/spl times/15 mm/sup 2/ and is easily fed by a 50 /spl Omega/ microstrip line printed on the same microwave substrate. Details of the design considerations for achieving dual-band operation, and experimental results of a constructed prototype for operating in the 2.4 and 5.2 GHz bands are presented.

Design of antenna radome composed of metamaterials for high gain

The design of antenna radome utilizing the left-handed materials at a frequency close to 5 GHz for the first time for enhancing the antenna gain is presented. We make use of the multi-layered structure composed of two materials with left-handed materials and air. The two materials have an average index of refraction around zero. The simulation results show that the antenna gain and the radiation patterns are effectively enhanced. The beamwidth is reduced by 37.5% and the antenna gain is increased to about 6 dBi. The results can be used in applications such as point-to-point communications between the buildings

Wideband monopole antenna integrated within the front-end module package

A novel wideband monopole antenna integrated within the front-end module package for WLAN and/or WiMAX operation in the 5 GHz band for a mobile device is presented. The front-end module package mainly comprises a bent /spl pi/-shaped wideband monopole antenna for 5 GHz band operation and a shielding metal case for accommodating the associated module and circuitry. The antenna is integrated to the shielding metal case through short-circuiting. For practical applications, the proposed front-end module package is to be mounted at one of the corners of the system circuit board of the mobile device. In this case, the shielding metal case not only performs as part of the ground plane of the antenna, but also functions as a shielding metal block to shield the antenna from the undesired coupling with nearby electronic or conducting elements in the mobile device. The proposed design of the front-end module package with an embedded antenna is studied, and obtained results of the constructed prototypes are presented.

Planar inverted-F antennas for GSM/DCS mobile phones and dual ISM-band applications

We present two novel PIFA designs for the GSM/DCS dual-band mobile telephones and 2.4/5.8 dual ISM-band applications. The first PIFA design uses three coplanar elements and has a compact size of 24/spl times/37/spl times/8.4 mm/sup 3/, which makes it very promising to be integrated within the mobile telephone housing as an internal dual-band mobile telephone antenna. The second PIFA design utilizes a driven smaller patch and a parasitic larger patch to achieve WLAN operation in the two ISM bands of 2.4 and 5.8 GHz, and occupies a small volume of 5/spl times/9/spl times/20 mm/sup 3/. Details of the design considerations of the proposed designs and the experimental results of the constructed prototypes are presented and discussed.

User's hand effects on EMC internal GSM/DCS mobile phone antenna

The users hand effects on the EMC GSM/DCS antenna embedded in the mobile phone have been presented. Although the EMC antenna is easy to be integrated into a mobile phone with nearby electronic components or conducting elements, the performance of the antenna is still greatly affected when a users hand holds the mobile phone. Even when the phone was hand-held at the bottom, large efficiency drops have been observed, especially for the GSM operation

Printed monopole slot antenna for multiband operation in the mobile phone

In this paper, we present a promising design of the monopole slot antenna for multiband operation in the mobile phone. The antenna is formed by two monopole slots of different lengths and is capable of multiband operation covering the AMPS/GSM/DCS/PCS/UMTS/WLAN bands. With multiband operation achieved in this study, however, the proposed printed monopole slot antenna requires a small area of 15 x 40 mm2 on the system circuit board of the mobile phone. Design considerations of the antenna are described in detail in the paper, and results for the constructed prototype are presented and discussed.