A Frequence-Reconfigurable Tuner-Loaded Coupled-Fed Frame-Antenna for All- Metal-Shell Handsets

A frequency-reconfigurable frame-antenna integrated with a coupling strip and tuner loading is proposed for all-metal-shell mobile telephones. The coupling strip introduces additional capacitance to the feeding structure of the antenna, rendering the antenna to resonate at both the lower frequency band at "a quarter-wavelength resonant mode" and the higher frequency band at "a half-wavelength resonant mode". Moreover, the antenna loaded with a tuner achieves broadband frequency-reconfiguration by tuning the effective length of radiating frame. The antenna is designed by taking into consideration all the metallic components, like front-and-back cameras, telephone receiver, and a steel sheet. The metal-frame and metal-shell of the handset coupled with a strip are used as parts of the antenna. This paper of a prototype operating in a practical handset test environment shows that the proposed antenna is able to cover the bandwidth of 824-960 MHz (GSM) and 1710-2690 MHz (DCS/PCS/UMTS/LTE) with acceptable radiation efficiency up to 40% and desirable patterns and specific absorption ratio, which is much lower than 1.6 W/kg for mobile communications.11Ysciescopu

Low-profile multiband planar hybrid antenna design for mobile handset applications

[[abstract]]A compact size planar microstrip-fed monopole antenna designed for mobile handset applications is proposed. To operate at global system for mobile communication (GSM)/global positioning system/digital communication system/personal communication system/universal mobile telecommunications system and 2.4-GHz wireless local-area network bands, a hybrid technique of joining the horizontal section of a T-monopole to an open-loop back coupling strip and loading a pair of monopole slot into the ground plane is used. Two operating bands are observed (along 3:1 VSWR) with the lower band covering only the GSM application, while the wide upper operating band covers the remaining applications. The effects on the antenna performances by tuning the various vital parameters have also been studied

Compact size planar folded PIFA design for mobile handset

[[abstract]]A printed compact size folded inverted-F antenna with simple configuration for mobile handset operating within the global system for mobile communication/personal communication system/digital communication system bands is initially proposed.To additionally cover the wireless local-area network frequency spectrum at 2.4 GHz, a narrow stub is protruded from the printed shorting wall. The excitation of these operating bands with desirable bandwidth is achieved by feeding a 50-Ω microstrip line to the folded radiating element through a via hole

Experimental studies of a shorted triangular microstrip antenna embedded with dual V-shaped slots

[[abstract]]The design of an equilateral triangular microstrip antenna embedded with dual V-shaped slots and two shorting walls is proposed and experimentally studied. By properly selecting suitable dimensions for this microstrip antenna, dual frequency operated at TM11 and TM21 modes, with frequency ratio ranging from 1.28 to 1.5 can be achieved with a single probe feed. The experimental procedures on achieving such operation with a maximum gain of around 11 dBi are presented and discussed

Multi-band loop antenna design for mobile devices

[[abstract]]The design of a novel microstrip-fed planar antenna for mobile devices operating within the GSM/PCS/DCS/UMTS band is proposed. Besides covering the WLAN, WiBro, and WiMAX spectra, its multiband features are also capable of operating in the GPS/GLONASS and MSS bands if navigation and satellite telecommunication applications are required. Impedance matching for these cases are simply achieved by tuning the slit embedded in the ground plane directly beneath the microstrip feed line

A circular-disc monopole antenna with band-rejection function for UWB application

[[abstract]]The numerical design method for a microstrip-fed circular-disc monopole (CDM) antenna operating within the ultrawideband (UWB) from 3.1 to 10.6 GHz is initially studied. By simply embedding a pair of U-shaped slots into the ground plane, a band-rejection (band-notch) function at around 5 GHz is achieved. For impedance matching and fine tuning of this proposed antenna, a small rectangular slit is inserted at the top centre of the ground plane. Except within the rejection band, the gain and time-domain characteristics of this antenna has successfully demonstrated that it is applicable to any high data rate short-range wireless communication system that requires a stable signal transmission in the UWB application. The performances of a common UWB CDM antenna without band-rejection function and a similar one with a slot loaded in the radiating circular patch are also investigated and compared with the proposed antenn

Dual-band antenna design for GPS and UMTS applications

[[abstract]]In this paper, a new design of an integrated antenna for the applications of GPS and UMTS is proposed. A broadband monopolar patch antenna with conical radiation patterns [5] is used as a radiating element for UMTS operation, and its radiating patch is placed at the inner-slot area of a circular-polarized (CP) square-ring microstrip element for GPS operation. Consequently, the two antenna elements of the proposed design can be fabricated on a single printed circuit board. In order to obtain the isolation of more than 20 dB between the two input ports, a 3rd Order Butterworth low pass filter (LPF) is designed and placed at the input port of the GPS antenna element. Details of the proposed design and obtained results are presented and discussed

Novel band-notch UWB antenna design with slit ground plane

[[abstract]]A newly designed microstrip feed, octagonal-shaped ultra-wideband printed antenna is proposed. The UWB operation within the required 3.1–10.6 GHz band is achieved by simply embedding in the ground plane a small rectangular slit, located below the feed line of an octagonal patch. With the dimensions (length and height) of the slit carefully tuned, a notched band of around 5.1–6.4 GHz can be achieved, without applying the commonly recommended techniques of loading the radiating patch with a slot or an open-ended slit

Design of an annular-ring microstrip antenna for circular polarization

[[abstract]]The design of an annular-ring microstrip antennas for circular polarization (CP) was discussed. For obtaining the CP operation of the annular-strip microstrip antenna, two orthogonal modes with equal amplitude and 90� phase difference were excited simultaneously. In order to excite orthogonal modes, a L-shaped strip was placed between inside the annular ring and its two ends were connected to the orthogonal modes of the inner boundary of the annular ring patch. The resonant frequency of x-polarized mode was higher than that of y-polarized mode, and thus a right-handed CP operation was obtained. The axial ratio of the CP radiation was also measured in the broadside direction

Printed UWB monopole antenna embedded with L-shaped slots in the ground plane for 5-GHz band-notch function

[[abstract]]An octagonal shaped microstrip-fed monopole antenna designed for UWB applications that operate within the 3.1 ∼ 10.6 GHz band is proposed. By applying a novel technique of embedding a pair of thin L-shaped slots in the ground plane, a band-notch function in the frequency band of around 4.95 to 5.98 GHz can be achieved for this antenna, so as to avoid interferences to the 5 GHz WLAN band. The time-domain characteristics of this antenna have further validates that it is suitable for any short-range mobile communication systems application