Conventional Planar inverted-F Antenna Research Articles

Metamaterial-Embedded Low SAR PIFA for Cellular Phone.

A metamaterial-embedded planar inverted-F antenna (PIFA) is proposed in this study for cellular phone applications. A dual-band PIFA is designed to operate both GSM 900 MHz and DCS 1800 MHz. The ground plane of a conventional PIFA is modified using a planar one-dimensional metamaterial array. The investigation is performed using the Finite Integration Technique (FIT) of CST Microwave Studio. The performance of the developed antenna was measured in an anechoic chamber. The specific absorption rate (SAR) values are calculated considering two different holding positions: cheek and tilt. The SAR values are measured using COMOSAR measurement system. Good agreement is observed between the simulated and measured data. The results indicate that the proposed metamaterial-embedded antenna produces significantly lower SAR in the human head compared to the conventional PIFA. Moreover, the modified antenna substrate leads to slight improvement of the antenna performances.

Design and analysis of metamaterial inspired low SAR PIFA for mobile phone

In this paper, a metamaterial embedded planar inverted-F antenna (PIFA) is proposed for cellular phone. A dual band PIFA is designed to operate both GSM 900 MHz and DCS 1800 MHz. The ground plane of conventional PIFA is modified using a double negati

A novel extended edge-based compact PIFA antenna for mobile devices

In this paper, an optimized ultra-compact planar inverted F antenna (PIFA) is proposed. Planar inverted F antenna (PIFA) is most commonly used antenna in modern day Mobile devices. While electronics industry is starving for compactness in their design, the concept used in the proposed design further reduces size of antenna. The overall dimensions of proposed antenna are 14.94×16mm for 3G/4G standards. In proposed design 21.61% size reduction is reported in comparison to conventional rectangular patch PIFA designs. The concept can be further utilized in designing antenna for different standards by optimizing size for specific frequency. A fractal shape Patch shorted at one end is used in the proposed design. The fractal patch is extended 6.59mm above the ground plane. The comparison is performed between measurement of fabricated and simulated S11 for proposed antenna. The novelty of design is inherited in extension of edges of patch towards ground which enable further reduction in size of antenna. Parametric optimization of antenna is performed for calculation of extended edge dimensions. Return loss for fabricated antenna is measured using vector network analyzer. The results of fabricated antenna show good agreement with simulated results and calculations.

Reconfigurable PIFA with a parasitic strip line for a hepta‐band WWAN/LTE mobile handset

In this study, a reconfigurable planar inverted-F antenna (PIFA) with a parasitic strip line for a hepta-band wireless wide area network (WWAN)/long term evolution (LTE) mobile handset is proposed. The PIN diode is located between the end of the parasitic strip line and the protruded ground plane. Depending on the on/off-state of the PIN diode, the degree of coupling between the conventional PIFA and the parasitic line is controlled and the fundamental resonant frequency of the proposed antenna is adjusted. As a result, the fundamental resonant frequencies cover the (global system for mobile communication) GSM850 (824–894 MHz) and GSM900 (880–960 MHz) bands. By the parasitic strip line extended from the protruded ground plane, impedance matching at the higher-order modes (f 2 and f 3) is improved and the fourth resonant frequency f 4 is remarkably decreased. The high band of the antenna is formed by combining these three higher-order modes to cover the GSM1800 (1710–1880 MHz), GSM1900 (1850–1990 MHz), universal mobile telecommunication system (UMTS) (1920–2170 MHz), LTE2300 (2305–2400 MHz) and LTE2500 (2500–2690 MHz) bands.

A frequency reconfigurable planar inverted‐F antenna for WWAN mobile handset applications

ABSTRACTIn this article, a reconfigurable antenna for wireless wide area network (WWAN) mobile handset application is proposed. The proposed antenna consists of a conventional planar inverted‐F antenna (PIFA), parasitic line, PIN diode, and bias line. The PIN diode is located between the parasitic line and ground, and its connection is electrically controlled by the on/off state of the PIN diode. The antenna's wide low band is formed by switching the quarter‐wavelength resonance mode of a conventional PIFA and covers the GSM850/900 bands. The antenna's high band is formed by the harmonic mode of a conventional PIFA and a new generated loop mode and covers the GSM1800/1900/UMTS bands. A stable and omnidirectional radiation pattern with a reasonable gain is observed over the operating bandwidth. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2888–2893, 2014

Multiband Loop Handset Antenna With Less Ground Clearance

In this letter, a loop antenna for multiband handset applications is proposed and investigated. The ground clearance required for the proposed antenna structure is relatively small in comparison to that of a conventional planar inverted-F antenna (PIFA) or a monopole with an antenna height of 0.013λo. The specific antenna geometry favors current large-display smartphones. The antenna radiates at three different modes, which cover GSM850/900/1800/1900/UMTS. An additional short on the loop controls high-frequency resonances.

Internal Hexa-Band Folded Monopole/Dipole/Loop Antenna With Four Resonances for Mobile Device

A fold monopole/dipole/loop antenna offers unique advantages over a conventional Planar Inverted-F Antenna (PIFA) and monopole antenna for a mobile cellular device. Perhaps the most significant benefit is the fact that up to three resonant modes could be generated in a single continuous loop structure. In this paper, a novel hexa-band internal folded monopole/dipole/loop antenna has been proposed. The proposed antenna has four resonances in which three of them are 0.5λ , 1λ and 1.5λ modes. The distinctive feature of the antenna is an extra 2λ folded dipole mode, which has not been reported so far, is excited and utilized. All these four modes can be employed to cover the Low LTE700/GSM850/900 Band (LB: 698-960 MHz) and the High GSM1850/1900/UMTS2100 Band (HB: 1710-2170 MHz). The proposed loop antenna has been simulated, prototyped and tested. It is shown that the numerically simulated results are in close agreement with the experimental prototype results and proved that the antenna operates as proposed.

Mobile handset antenna with double planar inverted-E (PIE) feed structure

Proposed is a novel mobile handset antenna with a double planar inverted-E (PIE) feed structure that achieves a wide impedance bandwidth. The antenna is designed by inserting two branch capacitors in the feed structure of a conventional planar inverted-F antenna. In the lower and higher frequency bands, the proposed antenna has a very wide impedance bandwidth characteristic, from 698 to 990 MHz, and from 1710 to 2170 MHz under a voltage standing wave ratio of 3:1 with good efficiency.

IMPEDANCE BANDWIDTH IMPROVEMENT OF BUILT IN ANTENNA BY NOVEL FEEDING STRUCTURE AT PRACTICAL MOBILE HANDSET

In this paper, we propose a wideband internal Planar Inverted-F Antenna (PIFA) by novel feeding structure at practical mobile handset. The proposed antenna by novel feeding structure shows 33.49% wideband impedance bandwidth, compared to 16.92% impedance bandwidth of normal feeding structure of PIFA. We explain novel feeding structure antenna by using equivalent circuit. The normal feeding structure of conventional PIFA has the inductive reactance structurally. To reduce its inductive reactance, a shunt inductive reactance using a novel feeding structure is added to normal feeding structure of conventional PIFA, structurally. So, reactance of PIFA is decreased and impedance bandwidth of PIFA is increased. The size of proposed antenna is 29:2 £ 8:2 £ 8:3mm 3 . As well as, the implemented antenna has a good radiation pattern and high antenna gains despite very small volume.

MD 매질을 이용한 이동통신용 Quad-Band 소형 안테나 설계 및 구현에 관한 연구

본 논문에서는 GSM850/GSM900/DCS1800/DCS1900 대역의 Quad-Band 안테나를 설계 및 제작하였다. 안테나의 소형화를 위해 MD(Magneto-Dielectric) 매질을 사용하여 기존의 PIFA(Planar Inverted-F Antenna) 안테나 보다 67.9%의 크기를 감소시켰으며, 광대역 특성을 얻기 위해 접지된 패치 구조로 커플링 방식을 이용한 간접급전 구조를 사용하였다. 제안한 안테나는 휴대 단말기에 적합한 소형화된 사이즈 (<TEX>$25\;mm\;{\times}\;10\;mm\;{\times}\;2\;mm$</TEX>)를 가지며, 동축 케이블을 이용하여 급전하였다. 또한 임피던스 대역폭은 VSWR < 3 (<TEX>${\leq}\;-6\;dB$</TEX>)에서 1341 MHz(801~2142 MHz)의 광대역 특성을 나타내며, 동작 대역에서 -6.67~4.25 dBi의 이득 및 전방향성 방사특성을 얻었다. In this paper, Quad-Band small antenna for GSM850, GSM900, DCS1800, DCS1900 is designed and fabricated. The antenna achieved the size reduction of over 67.9 % than the conventional PIFA(Planar Inverted-F Antenna) by using a MD(Magneto-Dielectric) material. A simple feeding microstrip line is used to feed the antenna from a <TEX>$50{\Omega}$</TEX> coaxial line, which is capacitively coupled to the grounded patch structure for broadband characteristics. The impedance bandwidth the proposed antenna shows good results as broadband characteristics of 1341 MHz (801 ~ 2142 MHz) in VSWR < 3 (<TEX>${\leq}\;-6\;dB$</TEX>) and the gain is -6.67 ~ 4.25 dBi in the operating frequency.

Improvement of radiation efficiency of radio frequency identification tag antenna for metallic objects printed on lossy substrate

A new antenna design method is proposed for radio frequency identification tags on metallic surfaces, using a low-cost, high-loss substrate such as FR4. The proposed method significantly reduces the dielectric loss of the substrate and so improves the radiation efficiency of the tag antenna by almost double compared with a conventional planar inverted-F antenna. The equivalent circuit model of the antenna designed is established and its characteristics analysed systematically. The superiority of the proposed design method is demonstrated and verified by fabricating a prototype antenna and presenting experimental results of the measurements obtained.

Planar Inverted-E (PIE) Antenna for a Wide Impedance Bandwidth

A planar inverted-E (PIE) antenna that can achieve a wide impedance bandwidth is proposed. The antenna is realized by inserting a branch capacitance between the feed line and the shorting pin of a conventional planar inverted-F antenna (PIFA). Such a modification significantly enhanced the impedance bandwidth while maintaining the antenna size. The proposed antenna possesses a very wide impedance bandwidth of 1250MHz (1650-2900MHz) at a voltage standing wave ratio (VSWR) <3. In addition, good radiation patterns were obtained at the desired frequency bands.

A Novel Modified Multiband Planar Inverted-F Antenna

A novel multiband modified planar inverted-F antenna (PIFA) with a compact single feed is proposed, which covers GSM900 (880-960 MHz), DCS (1710-1880 MHz), PCS (1850-1990 MHz), UMTS (1920-2170 MHz), Bluetooth/WLAN (2400-2480 MHz), WiMAX (2500-2690 MHz), HiperLAN/2 (5470-5725 MHz), and an additional band (4600-4800 MHz). In conventional PIFA, most of time the shorted pin acts as a capacitor load only for impedance matching purpose, which may yield a large ground plane, narrow bandwidth, and large antenna volume due to a long shorted pin to provide enough capacitance. In our design, the shorted pin just acts a short-circuited load, which is an effective way to control the current resonant paths and is a novel way in design a multiband PIFA. Furthermore, with this design and parasitic folded structures, the proposed multiband antenna can be modeled by parallel short-circuited transmission line impedance transformers (TLIT), which can easily create six mentioned frequency bands (from PCS band to HiperLAN/2 band) by adjusting the lengths of folded branches. Measurement result conforms that our multiband design not only provides size reduction of both the antenna and the ground plane but also enhances the bandwidth of the six bands.

Wideband‐integrated planar inverted‐F antenna with meander line structures

AbstractAn improved wideband planar inverted‐F antenna (PIFA) is investigated in this work. The meander line structure is introduced into the conventional PIFA and significant bandwidth improvement can be observed. Two improved PIFA antennas with different meander line structures are designed and fabricated; the measured results show good agreement with the simulations, demonstrating 23.1 and 40% bandwidth at −10 dB return loss, about 131 and 300% bandwidth enhancement, respectively, compared with the original PIFA (less than 10%). Obviously, the proposed antenna demonstrates good performances (especially in bandwidth), compact size, low profile, and low cost; it is thus expected to find possible applications in wireless communication systems. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 384–387, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24046

손실 기판을 이용한 금속 부착형 RFID 태그 안테나의 복사 효율 향상

본 논문에서는 FR4와 같은 저가의 고손실 기판을 이용하여 금속 부착형 태그 안테나를 설계하는 새로운 방법을 제안한다. 제안한 설계 방법은 유전 손실(dielectric loss)에 따른 기판 손실(substrate loss)을 크게 감소시킴으로써, 태그 안테나의 복사 효율(radiation efficiency)을 기존의 평면 역 F 안테나(planar inverted-F antenna: PIFA)에 비하여 2배 이상 향상시킨다. 본 논문에서는 제안한 방법에 따른 안테나의 등가 회로 모델을 정립하고 이를 체계적으로 분석하였으며, 시제품을 제작 및 측정하여 제안한 방법의 우수성을 입증하였다. In this paper, we propose a new antenna design method for RFID tass on metallic surfaces using a low-cost, high-loss substrate such as FR4. The proposed design method highly reduces the substrate loss due to its dielectric loss, and so improves the radiation efficiency of the tag antenna more than double compared with a conventional PIFA(planar inverted-F antenna). The equivalent circuit model of the antenna according to the proposed method was established and its characteristics were analyzed systematically in this paper. The excellency of the proposed design method was verified by the fabrication and measurement of a prototype antenna.

Design of RFID tag antenna for metallic surfaces using lossy substrate

A novel low-cost antenna design suitable for radio frequency identification (RFID) tags mountable on metallic surfaces is presented. The antenna consists of two shorted patches printed on a lossy FR4 substrate and their radiating edges are facing each other. A tag chip feed is placed between two patches and a stacked shunt capacitor is formed to adjust the antenna impedance. The proposed design reduces the substrate loss and improves the radiation efficiency by more than double compared with a conventional planar inverted-F antenna, which is verified by simulation and measurement.

Channel capacity of dual-element modified PIFA array on small mobile terminal

A study on the MIMO channel capacity of a modified dual-element planar inverted-F antenna (PIFA) array is presented. The dual-element PIFA array consists of two modified PIFAs which are mounted on a small mobile terminal operating at 2.5 GHz. The relationship between mutual coupling and channel capacity is analysed by comparing the modified dual-element PIFA array with a conventional dual-element PIFA array and two ideal dipoles.

A Tunable Via-Patch Loaded PIFA With Size Reduction

A novel tunable planar inverted-F antenna (PIFA) is described. A via-patch is introduced under the main radiating element to create a capacitive coupling effect and lower the operating frequency. The antenna size is reduced by half when compared to the conventional PIFA. Incorporating with an L-shaped opening on the ground plane, the proposed via-patch loaded PIFA exhibits a 10-dB return-loss bandwidth of 8.91% for 2.4 GHz ISM band applications. In the proposed approach, the capacitive patch is connected to the ground through a via while a coaxial feed is directly connected to the radiating element. This is different from other capacitive-loading, size-reduction schemes in which the capacitive patch is connected to the coaxial feed, thus not able to provide frequency tuning. By simply replacing the via in our antenna with a screw and adjusting the height of the via-patch by turning the screw, a tuning range of 0.8 GHz from 2.5-3.3 GHz can be achieved. This makes the proposed PIFA a convenient tunable small antenna. Both simulation and measurement results are presented together with parametric studies on the via-patch and L-shaped opening ground plane

A miniaturized Hilbert PIFA for dual-band mobile wireless applications

A miniaturized planar inverted-F antenna (PIFA) is proposed for dual-band mobile phone application in the 900- and 1900-MHz bands. By employing a Hilbert geometry, an overall size reduction of 50% was achieved compared to a conventional rectangular PIFA. The proposed antenna can be easily printed on the inside surface of the plastic housing of a mobile phone or other wireless device. An experimental prototype of this miniature antenna was fabricated on 0.125 mm thick Duroid 5880 substrate. Measured results demonstrate dual-band characteristics with good radiation patterns.

Planar inverted‐F antenna with slotted ground plane

AbstractBy embedding a group of parallel slots in the ground plane, novel dual‐frequency operations of a single‐feed planar inverted‐F antenna (PIFA) are presented. Simulation based upon the method of moments (MoM) is used to model the performance of the antenna. An example of the proposed antenna is fabricated to validate the simulation, and the experimental results show that the 10‐dB return‐loss impedance bandwidths are about 9% and 8.4% for frequency bands of 1.9 and 2.4 GHz, respectively. In addition, the measured radiation patterns in the two frequency bands are similar to that of a conventional planar inverted‐F antenna. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 72–75, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11131