Carles Puente

Multiband Handset Antenna Combining a PIFA, Slots, and Ground Plane Modes

A multiband handset antenna combining a PIFA and multiple slots on a ground plane is presented. It is shown by means of simulations that the slots on the ground plane have a double function: to tune the ground plane resonance at low frequencies (f ¿ 900 MHz) and to act as parasitic radiators at high frequencies (f ¿ 1800 MHz). A prototype is designed and built featuring a behavior suitable for low frequencies (GSM850 and GSM900) and for high frequencies spanning from DCS1800 to Bluetooth, and including, for instance, PCS1900, UMTS2000, and other possible systems. Reflection coefficient, efficiency, and radiation patterns are measured and compared with a design without slots to prove the advantages of the slotted ground plane. The component effect is investigated to determine critical areas where the placement is not recommended. Besides, the effect of the slot of the ground plane on SAR is investigated, by discussing the effect of the ground plane and slot modes for two phone positions. The total antenna volume of the proposed design is 40 × 15 × 6 mm3.

Broad-band dual-frequency microstrip patch antenna with modified Sierpinski fractal geometry

A dual-frequency antenna based on the Sierpinski fractal with two parasitic patches to enhance the impedance bandwidth is presented. An electrical circuit model formed by RLC resonators is proposed to learn about the antenna physical behavior and to achieve the dual band operation minimizing a trial-and-error numerical/measurement proofs. The antenna has been designed using a method of moment commercial code and has been experimentally tested, obtaining two bands with a broad bandwidth and similar radiation patterns.

Multiband Handset Antenna With a Parallel Excitation of PIFA and Slot Radiators

A handset antenna technique combining a parallel excitation of a PIFA and a slot is presented. The number of frequency bands is given by the sum of bands given per each radiator which can be controlled independently. Component interaction (battery, display, and speaker) is analyzed to determine the best place to mitigate performance degradation. Finally, a concept featuring a small footprint (39 × 11 mm2) and low profile (2 mm) is proposed for multiband operation.

Stacked H-shaped microstrip patch antenna

A small H-shaped microstrip patch antenna (MPA) with enhanced bandwidth is presented. The H-shaped antenna is first studied by a transmission line model and then is fully analyzed with a MoM code. A stacked patch configuration is proposed to increase the narrow bandwidth, radiation efficiency and directivity. The stacked H-shaped MPA is studied using Chus fundamental limit for electrically small antennas.

Ground Plane Boosters as a Compact Antenna Technology for Wireless Handheld Devices

The increasing demand for multifunctional wireless devices has fostered the need to reduce the space devoted to the antenna in order to favor the integration of multiple and new functionalities. This fact becomes a challenge for the handset antenna designers who have to develop antennas capable of providing multi-band operation constrained by physical limitations. This proposal consists in a radiating system capable of providing multi-band operation without the need of an antenna element, by properly exciting the efficient radiation modes associated to the ground plane structure. In this sense, the typical volume devoted to a handset antenna is reduced by a factor of 20. The electrical model approximation of the radiating structure leads to the radiofrequency system design able to provide multi-band operation. The feasibility of the proposal has been tested by electromagnetic simulations as well as by experimental measurements regarding the main antenna parameters: reflection coefficient, efficiency, and radiation patterns. Furthermore, the human head interaction concerning biological compatibility in terms of SAR (Specific absorption rate) has been measured and a solution for its reduction is presented. As a result, a promising standard solution for a radiating system capable to operate in the main communication standards GSM850, GSM900, DCS, PCS and UMTS is provided with a volume reduction factor around 20.

Dual-Frequency Broadband-Stacked Microstrip Antenna Using a Reactive Loading and a Fractal-Shaped Radiating Edge

A dual-band enhanced-bandwidth microstrip antenna is presented with a frequency separation of f2/f1=1.37. In order to achieve the dual-frequency operation, a rectangular patch antenna is reactively loaded with a stub placed along one of the radiating edges. Then, the bandwidth is enhanced using a stacked parasitic technique, whereas the matching and radiation characteristics are kept constant along each band and similar at two bands.

MULTIBAND HANDSET ANTENNA USING SLOTS ON THE GROUND PLANE: CONSIDERATIONS TO FACILITATE THE INTEGRATION OF THE FEEDING TRANSMISSION LINE

Technology and Intellectual Property Rights DepartmentFractusBarcelona, SpainS. KahngDepartment of Info. & Telecomm. Eng.University of IncheonIncheon, South KoreaAbstract—This research consists on a ground plane modificationusing slots of a PIFA (Planar Inverted F Antenna) handsetantenna with the objective to facilitate the integration of thefeeding transmission line which connects the antenna with the RF-module. Through this technique it is possible to obtain a multibandantenna while keeping the same antenna geometry, small volume

Advances in Antenna Technology for Wireless Handheld Devices

The constant evolution of wireless handheld devices together with the apparition of multiple wireless communication systems fosters the antenna community to design new radiating and measurements systems capable of satisfying the market demands. It is an object of the present paper to provide an overview of the evolution that wireless handheld technology has experienced in the last years. In this sense, a description of the evolution of wireless handheld devices, regulations, challenges in today’s smartphones, and handset characterization is reviewed. Finally, recent advances in antenna technology for wireless handheld or portable devices are presented.

Metallized Foams for Antenna Design: Application to Fractal-Shaped Sierpinski-Carpet Monopole

The technology of metallized foam offers a new approach to design wire-like, flat, and 3D antennas. Only the necessary metal skin depth (some microns in UHF band) is deposited over arbitrary shaped structures. Thanks to this technology, new antenna designs have been possible offering low weight, possible shaping, and innovative Corresponding author: J. Anguera (jaume.anguera@fractus.com). † Also with Electronics and Telecommunications Department, Universitat Ramon Llull, Barcelona, Spain. ‡ Also with Signal Theory and Communications Dept., Universitat Politecnica de Catalunya, Barcelona, Spain.

Metallized foams for fractal-shaped microstrip antennas

An antenna manufacturing process using metallized foams is presented. A microstrip-patch antenna, inspired by the Koch island geometry, embedded in a rectangular cavity is built and tested. All the metallic parts of the antenna (patch, cavity, and feeding probe) were metaliized on the foam, resulting in a low-weight and low-complexity antenna structure. The results of return loss, directivity as a function of frequency, radiation pattern for several modes, and radiation efficiency have been compared with simulated data, resulting in very good agreement.