Showing papers on "Folded inverted conformal antenna published in 2012"
TL;DR: Fundamental antenna design tradeoffs of multiple antenna terminals are presented in the framework of characteristic mode analysis and it is revealed that the characteristic modes play an important role in determining the optimal placement of antennas for low mutual coupling.
Abstract: The design of multiple antennas in compact mobile terminals is a significant challenge, due to both practical and fundamental design tradeoffs. In this paper, fundamental antenna design tradeoffs of multiple antenna terminals are presented in the framework of characteristic mode analysis. In particular, interactions between the antenna elements and the characteristic modes and their impact on design tradeoffs are investigated in both theory and simulations. The results reveal that the characteristic modes play an important role in determining the optimal placement of antennas for low mutual coupling. Moreover, the ability of antenna elements to localize the excitation currents on the chassis can significantly influence the final performance. To demonstrate the effectiveness of the proposed approach, a dual-band, dual-antenna terminal is designed to provide an isolation of over 10 dB for the 900 MHz band without additional matching or decoupling structures. A tradeoff analysis of bandwidth, efficiency, effective diversity gain and capacity is performed over different antenna locations. Finally, three fabricated prototypes verify the simulation results for representative cases.
211 citations
TL;DR: In this article, a printed wide-slot antenna with a parasitic patch for bandwidth enhancement is proposed and experimentally investigated, which exhibits a wide impedance bandwidth, which is over 80% for |S11| ≤ -10 dB ranging from 2.23 to 5.35 GHz.
Abstract: A printed wide-slot antenna with a parasitic patch for bandwidth enhancement is proposed and experimentally investigated. A simple 50-Ω microstrip line is used to excite the slot. A rotated square slot resonator is considered as reference geometry. The rotated square slot antenna exhibits two resonances (f1 : lower resonant frequency, f2: higher resonant frequency). By embedding a parasitic patch into the center of the rotated square slot, the lower resonant frequency is decreased and the higher resonant frequency is increased. Thus, broadband characteristic of the wide-slot antenna is achieved. The measured results demonstrate that this structure exhibits a wide impedance bandwidth, which is over 80% for |S11| ≤ -10 dB ranging from 2.23 to 5.35 GHz. Also, a stable and omnidirectional radiation pattern is observed within the operating bandwidth. In this design, a smaller ground plane is considered compared to the reference antenna (rotated square slot antenna without the parasitic center patch).
172 citations
TL;DR: In this article, a folded loop-inverted F reconfigurable antenna for mobile phone applications is designed and the obtained results are discussed in this communication, which operates in hepta-band, including GSM850, GSM900, GPS, DCS, PCS, UMTS and WLAN, with the return loss lower than 6 dB.
Abstract: 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 mm3, 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.
144 citations
31 Aug 2012
TL;DR: In this article, a design of stacked rectangular dielectric resonator antenna (RDRA) with wide bandwidth, in the range of 13.56 % is described, which exploits two low-Q modes with overlapping bandwidths to achieve a wide continuous bandwidth.
Abstract: This paper presents a design of stacked rectangular dielectric resonator antenna (RDRA) with wide bandwidth, in the range of 13.56 % is described. The antenna exploits two low-Q modes with overlapping bandwidths to achieve a wide continuous bandwidth. This is achieved using low-permittivity DRA volume placed on high permittivity DRA volume. The antenna consists of dielectric constant of 10 and 32, stacked vertically to obtain improved bandwidth as compared to the conventional RDRA. A 50 Ω microstrip line is used in the proposed antenna as a feeding mechanism. Physical parameters of stacked RDRA have been optimized by extensive simulations using Ansoft HFSS. The parameters of antenna are 17x7x4.56 mm 3 with grounded substrate size: 80x50 mm 2 . The prototype is fabricated. Measured and simulated results are both in good agreement. The prototype antenna designed to operate in band from 5.0 to 5.7 GHz with measured gain at 5.2 GHz resonant frequency. The proposed antenna is suitable for wireless local area networks (WLAN) applications in 5 GHz frequency band (in the frequency range 5.15-5.35 GHz and 5.5-5.7 GHz). This stacked RDRA exceeds the bandwidth requirements for IEEE 802.11a WLAN applications within a required VSWR. Parametric studies of the stacked DRA are presented.
126 citations
TL;DR: In this article, a fold monopole/dipole/loop antenna with four resonances in which three of them are 0.5λ, 1λ, 1λ and 15λ modes has been proposed.
Abstract: 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.
115 citations
TL;DR: In this article, a folded monopole ESPAR antenna is proposed to reduce the size of the antenna by using a top-disk loaded monopole and six folded monopoles as the driven element and parasitic elements, respectively.
Abstract: A compact low-cost low-power smart antenna has been proposed in this paper. To reduce the cost and power consumption, it employs the structure of an Electronically Steerable Parasitic Array Radiator (ESPAR) antenna. To reduce the size of the antenna, a top-disk loaded monopole and six folded monopoles are employed as the driven element and parasitic elements, respectively. The proposed antenna is called “folded monopole ESPAR antenna”. The heights of the top-disk loaded monopole and folded monopoles are reduced to be less than . Furthermore, the radius of the folded monopole ESPAR antenna is reduced by using capacitive loading technique. An equivalent circuit model is proposed for analyzing the antenna. To validate the concept, a prototype is developed and the antenna operates from 2.3 GHz to 2.55 GHz. The measured results confirm that the folded monopole ESPAR antenna can achieve electronically beam scanning in horizontal plane over a 360 range. The prototype antenna achieves a gain of 4.0 dBi and a front-back ratio of 20 dB. The parasitic elements are loaded by varactors and beam forming is achieved by controlling the DC voltages applied to the varactors.
100 citations
TL;DR: In this paper, a technique for enhancement of bandwidth and efficiency of a cavity-backed slot antenna is proposed, which removes the substrate under the slot to decrease the capacitance of the slot.
Abstract: A technique for enhancement of bandwidth and efficiency of a cavity-backed slot antenna is proposed. The bandwidth of the cavity-backed slot antenna depends on the Q of the slot and the cavity. The proposed technique removes the substrate under the slot to decrease the capacitance of the slot. Because a half-wavelength slot is considered a parallel resonant circuit at resonant frequency, lowered capacitance increases the bandwidth of the antenna. Antenna efficiency also can be enhanced by the proposed technique. The dielectric loss, which is produced by the E-field across the slot, is effectively decreased by removing the substrate under the slot. Various simulation results of demonstration of the proposed technique are given. The proposed antenna, which was fabricated on a 2-mm-height FR-4 substrate, shows 6.2% higher antenna efficiency and 24% wider bandwidth compared to the conventional cavity-backed slot antenna, which has a whole substrate. The proposed technique is effective in enhancing the efficiency and bandwidth of a cavity-backed slot antenna.
85 citations
TL;DR: In this article, a planar inverted F-shaped antennas (PIFA) constructed by a meandered line and folded patch with interdigitated capacitive strips connected to the folded patch is presented.
Abstract: A novel quad-band diversity antenna is presented with two radiating elements suitable for long-term evolution (LTE) and wireless fidelity (Wi-Fi) applications in handheld devices. The radiating elements are two planar inverted F-shaped antennas (PIFA) constructed by a meandered line and folded patch with interdigitated capacitive strips connected to the folded patch. To achieve high isolation between the two radiating elements, a defected ground plane (a combination of rectangular slot ring and inverted T-shaped slot stub) is employed. The antenna is designed to operate in the 746-787 MHz, 1850-1990 MHz, 1920-2170 MHz, and 3600-3700 MHz frequency bands. The characterization of the antenna in free-space as well as in the proximity of the user head and hand is presented. The results confirm the excellent performance of the proposed diversity antenna.
85 citations
TL;DR: In this paper, a folded ultrawideband antenna for WBAN is proposed, which can effectively reduce the backward radiation and proximity effects of human bodies, which shows the directional patterns with low backward radiation due to the patch-like structure.
Abstract: A novel folded ultrawideband antenna for Wireless Body Area Network (WBAN) is proposed, which can effectively reduce the backward radiation and proximity effects of human bodies. The proposed antenna has a low-profile 3D structure that consists of a bevel-edge feed structure and a metal plate with folded strip. The bevel edge feed structure achieves broadband impedance matching and the metal plate acts as the main radiator. Moreover, the folded strip not only extends the lower frequency band but also provides additional resonant frequency around 6 GHz. The final bandwidth covers from 3.1 GHz to 12 GHz. The proposed antenna shows the directional patterns with low backward radiation due to the patch-like structure and the ground plane also prevents from the proximity effects of human bodies. Furthermore, the simulated SAR values of the proposed antenna are lower than the values of omnidirectional disc planar monopole. These features demonstrate that the proposed antenna is suitable for WBAN application.
83 citations
TL;DR: In this article, the authors proposed a compact planar inverted-F antenna (PIFA) operating at 2.45 GHz for on-body communications, which is low profile and compact in size, and does not change significantly when in close proximity to the human body.
Abstract: Body-centric wireless communications (BCWCs) have received a great deal of attention recently. This communication proposes a compact planar inverted-F antenna (PIFA) operating at 2.45 GHz for on-body communications. Two shorting structures and a folded ground plane are used to improve the impedance matching and decrease the size of the proposed antenna. As a result, the proposed antenna is low-profile and compact in size, and it does not change significantly when in close proximity to the human body. This communication studies the characteristics of the proposed antenna close to the arm phantom by simulation and experiments. Both simulated and measured results are in good agreement.
74 citations
TL;DR: A broadband yet compact antenna design applicable to tablets and laptops is proposed, which provides an extensive coverage for existing and upcoming mobile communication bands and exhibits broad resonant bandwidth.
Abstract: A broadband yet compact antenna design applicable to tablets and laptops is proposed. The antenna provides an extensive coverage for existing and upcoming mobile communication bands. Several band broadening and antenna miniaturization techniques were employed, including the use of a parasitic element, meandered structures, branched structures and a lump component. The proposed design is planar, compact and can be fabricated via printed circuit board technology. Measurement results exhibits broad resonant bandwidth. Nearly omni-directional patterns and reasonable radiation efficiency are observed.
Journal Article•
TL;DR: In this article, a single feed compact square microstrip antenna with two L slits on the right edge of the patch is proposed to study the effect of the slit on radiation behavior with respect to a conventional microstrip patch.
Abstract: - A single feed compact square microstrip antenna is proposed in this paper. Two L slits are introduced on the right edge of the patch to study the effect of the slit on radiation behavior with respect to a conventional microstrip patch. An extensive analysis of the return loss, radiation pattern and efficiency of the proposed antenna is shown in this paper. For the optimize value of the slit parameters antenna resonant frequencies are obtained at 2.16, 2.68,3.22&4.37 GHz with corresponding bandwidth 11.02 MHz, 13.07 MHz, 35.86 MHz , 48.56 MHz and return loss of about -23.4,-15.2,-30.6&-20.3 dB respectively. For the lowest esonant frequency (2.16 GHz) the size of the antenna has been reduced by 71.14 % when compared to aconventional rectangular microstrip patch. Thecharacteristics of the designed structure are nvestigated by using MoM based electromagnetic solver, IE3D. The simple configuration, low profile nature, reduced size and quad band characteristics of the proposed antenna makes it suitable to operate in the frequency ranges of 2.165-2.176, 2.673-2.686, 3.208-3.244 and 4.343-4.392 GHz.
TL;DR: In this paper, a coupled-fed planar printed antenna mounted on the compact no-ground portion of the system circuit board of a mobile phone with a low proflle of 10mm is proposed and studied.
Abstract: In this article, a coupled-fed planar printed antenna mounted on the compact no-ground portion of the system circuit board of a mobile phone with a low proflle of 10mm is proposed and studied. The presented antenna is formed by a double-branch feeding strip, a shorted coupling strip with two open-ended loops of difierent lengths, and a slotted ground structure consisting of two monopole slots, yet it has a size only 15 £ 50mm 2 . Two wide operating bandwidths of 698{960MHz and 1710{2690MHz can be achieved by these radiating strips, which provide multiple resonant modes at about 750, 1000, 1750, 2300 and 2900MHz. In addition, with the presence of the two narrow slots and a chip inductor (L = 1:5nH), in this study, the printed antenna can lead to much widened bandwidths in both the antenna's lower and upper bands to cover LTE700/GSM850/900 and DCS1800/PCS1900/UMTS2100/LTE2300/2500, respectively. Good radiation e-ciency and antenna gain for frequencies over the desired operating bands are obtained. Detailed design considerations of the proposed antenna are described, and both experimental and simulated results are also presented and discussed.
TL;DR: In this article, a 15.5 × 56.5mm2 planar slot antenna operated under the surroundings of an unbroken metal rim in mobile handsets is introduced, where the height of the slot antenna is shortened, and the bandwidth for low band is expanded to cover both GSM850 and GSM900.
Abstract: This letter introduces a 15.5 × 56.5-mm2 planar slot antenna operated under surroundings of an unbroken metal rim in mobile handsets. The height of the slot antenna is shortened, and the bandwidth for low band is expanded to cover both GSM850 and GSM900. This antenna provides a solution for planar unbroken metal-rimmed handsets and can be operated in five wireless communication bands (i.e., GSM850, GSM900, DCS1800, PCS1900, and UMTS bands). Good performances on return loss, radiation pattern, efficiency, and gain are obtained over these five operating bands. Hand effect of this slot antenna is also studied by comparison to the conventional monopole antenna.
TL;DR: In this article, an internal planar tablet computer antenna having a small size of 12 × 35 mm2 printed on a 0.8mm thick FR4 substrate for the WWAN operation in the 824-960 and 1710-2170 MHz bands is presented.
Abstract: An internal planar tablet computer antenna having a small size of 12 × 35 mm2 printed on a 0.8-mm thick FR4 substrate for the WWAN operation in the 824-960 and 1710-2170 MHz bands is presented. The antenna comprises a driven strip, a parasitic shorted strip and a ground pad, all printed on the small-size FR4 substrate. For bandwidth enhancement of the antenna's lower band, the antenna applies a parallel-resonant spiral slit embedded in the ground pad, which generates a parallel resonance at about 1.2 GHz and in turn results in a new resonance occurred nearby the quarter-wavelength mode of the parasitic shorted strip. This feature leads to a dual-resonance characteristic obtained for the antenna's lower band, making it capable of wideband operation to cover the desired 824-960 MHz with a small antenna size. The antenna's upper band is formed by the higher-order resonant mode contributed by the parasitic shorted strip and the quarter-wavelength resonant mode of the driven strip and can cover the desired 1710-2170 MHz band. Details of the proposed antenna and the operating principle of the parallel-resonant spiral slit are presented.
TL;DR: In this paper, a single-layer circularly polarized reflectarray antenna is proposed to achieve more than 650° of linear phase for frequencies in the range 9.6-11.2 GHz.
Abstract: The design and implementation of a broadband single-layer circularly polarized reflectarray antenna is presented in this letter. Each element in the proposed reflectarray consists of a circular microstrip patch attached to four variable-length phase delay lines to achieve more than 650° of linear phase for frequencies in the range 9.6-11.2 GHz. Measurement results show 15.5% 3-dB gain bandwidth and 14.6% 3-dB axial-ratio bandwidth.
TL;DR: This work proposes an alternative novel decoupling technique, investigating several multiple antenna configurations for small handsets through measurements and numerical simulations, and shows that antennas may experience very different losses and envelope correlation coefficients depending on their relative position with respect to the handset.
Abstract: In multiple antenna systems mutual coupling needs to be minimized. We propose an alternative novel decoupling technique, investigating several multiple antenna configurations for small handsets through measurements and numerical simulations. The influence of different novel designs on performance metrics such as total loss, antenna isolation and envelope correlation coefficient are investigated. By varying antenna impedance bandwidth and antenna location with respect to the handset, both planar inverted F antenna (PIFA) and inverted F antennas (IFA) were investigated in different UMTS frequency bands in proximity with the user's body. Results show that antennas may experience very different losses and envelope correlation coefficients depending on their relative position with respect to the handset, as the influence of the user's hand is not symmetrical in most cases. Narrow-band antennas are inherently decoupled when integrated on the same handset, while also other parameters such as frequency duplex distance and interaction with the user's body influence the mutual coupling.
TL;DR: In this paper, a broadband circular polarized two-element planar inverted-F antenna (PIFA) with pattern diversity and high isolation for multimode satellite navigation is reported, where a cross branch at its corner of the ground is introduced to give the antenna a broadband impedance bandwidth characteristic.
Abstract: A broadband circular polarized two-element planar inverted-F antenna (PIFA) with pattern diversity and high isolation for multimode satellite navigation is reported. Circular polarization characteristic of the proposed antenna is achieved by introducing a cross branch at its corner of the ground. The modified PIFA structure gives the antenna a broadband impedance bandwidth characteristic. A prototype is fabricated and measured. The results show that this circular polarized antenna with compact dimension has broadband from 1.1 to 1.7 GHz and good isolation of 14 dB between the two elements over the whole band, which makes the antenna suitable for handheld terminal application of multimode satellite navigation.
TL;DR: In this article, a frequency-reconfigurable folded slot antenna that operates in two modes has been proposed, and it can be used in WLAN band (5.15-5.35 GHz) and WiMAX band (3.40-3.69 GHz).
Abstract: This letter presents a novel frequency-reconfigurable folded slot antenna that could operate in two modes. Both modes have two resonant frequencies. The first mode resonant frequencies are at 3.4 and 5.27 GHz, and it can be used in WLAN band (5.15-5.35 GHz) and WiMAX band (3.40-3.69 GHz). The second mode operating frequencies are at 2.42 and 5.79 GHz, and they can be used in WLAN band (5.725-5.875 GHz) and Bluetooth band (2.40-2.484 GHz). The simulated results both for the return loss and peak gain agree with the measurements. Both the slot and arms of the proposed folded slot antenna are used to result in a resonant frequency, respectively. The advantage of this design is that the antenna is easy to fabricate, and this antenna could work without a complex bias network and a dc blocking capacitor.
TL;DR: In this paper, a switched antenna that has a capability to operate in the dual-band WLAN frequency bands (2.4-2.5 GHz) and the band-notched ultrawideband (UWB) frequency band (the stopband covers the frequency band ranging from 5.15 to 5.825 GHz) is presented.
Abstract: A switched antenna that has a capability to operate in the dual-band WLAN frequency bands (2.4-2.485, 5.15-5.35, and 5.725-5.825 GHz) and the band-notched ultrawideband (UWB) frequency band (the stopband covers the frequency band ranging from 5.15 to 5.825 GHz) is presented. The proposed antenna is composed of a rectangular ring slot, four switches, a coplanar waveguide (CPW) feeding line, a T-shaped stub, and two inverted S-shaped slots. The function of the two inverted S-shaped slots can be changed by tuning status of the switches that make the operating bands of the proposed antenna various. To the authors' knowledge, a feature that the antenna is able to cover two complementary bands is unique to this letter.
TL;DR: In this article, a dual-feed planar inverted-F antenna (PIFA) was proposed for wireless applications such as wireless local area network (WLAN) and long term evolution (LTE) as a diversity and multiple-input multiple-output (MIMO) antenna.
Abstract: This work presents a novel dual-feed planar inverted-F antenna (PIFA) suitable for wireless applications such as wireless local area network (WLAN) and long term evolution (LTE) as a diversity and multiple-input multiple-output (MIMO) antenna. Instead of two antenna elements, there is only one top radiating element with two isolated feeding ports which can save space and cost. The two feed plates are placed perpendicular to each other to exploit both the polarization diversity and pattern diversity. The isolation between the two antenna ports is achieved by modifying the ground plane under the top radiating element. Simulated and measured results are obtained to verify the conclusion .
TL;DR: In this article, the feasibility of using a circular microstrip patch antenna to measure strain and the effects of different materials on sensitivity of the patch antenna are investigated, and the effect of different material types on the antenna is investigated.
Abstract: In this article, the feasibility of using a circular microstrip patch antenna to measure strain and the effects of different materials on sensitivity of the patch antenna are investigated. Also, th...
TL;DR: An optimization technique for microstrip patch antenna using Curve Fitting based Particle Swarm Optimization (CFPSO) is presented and it is shown that CFPSO showed remarkable improvement over bandwidth.
Abstract: An optimization technique for microstrip patch antenna using Curve Fitting based Particle Swarm Optimization (CFPSO) is presented in this paper. An E-H shaped patch antenna designed using conventional optimization technique for Ultra Wide Band (UWB) communication is utilized to demonstrate the optimization technique. The conventional optimized antenna is designed by searching an acceptable solution from amongst the invariably huge collective range of geometry variables. The data for curve fitting is obtained from EM simulator by varying different geometrical parameters of the antenna. Using the data, the equations representing the relationship among different parameters of a microstrip antenna are generated. Curve fitting software was used to generate the curve. The CFPSO program was developed and executed in MATLAB. Conventionally optimized antenna is compared with CFPSO optimized antenna in this paper. The result yields that CFPSO showed remarkable improvement over bandwidth. For the E-H shaped antenna,...
Patent•
17 Jul 2012TL;DR: In this article, the authors describe a multiband antenna with adjustable tuning circuits that can be disposed between separate and displaced radiating segments of a respective one of the first and second radiating portions.
Abstract: A system and process that includes a multiband antenna as may be used in mobile communications devices. The multiband antenna includes a feed port coupled to each of a first radiating portion and a second radiating portion. Each of the first and second radiating portions defines a respective resonant bandwidth. The multiband antenna also includes at least one adjustable tuning circuit disposed between separate and displaced radiating segments of a respective one of the first and second radiating portions. Adjustment of the tuning circuit alters a corresponding resonant bandwidth allowing the corresponding resonant bandwidth to be tuned independently of the other resonant bandwidth and without affecting performance of the other resonant bandwidth. Other embodiments are disclosed.
TL;DR: In this article, the Theory of Characteristic Modes (TCMs) is used to achieve pattern diversity in order to be used in multiple-input-multiple-output (MIMO) applications.
Abstract: In this letter, the Theory of Characteristic Modes (TCMs) is used to achieve pattern diversity in order to be used in multiple-input-multiple-output (MIMO) applications. It is shown that TCMs can orient the design procedure by providing an insight into the natural behavior of the analyzed radiating part of the structure. A metallic equilateral triangular-shaped plate is analyzed by TCMs, and its first seven characteristic modes are obtained. Among them, there are two sets of degenerative modes. All these modes are orthogonal. To achieve pattern diversity, it is essential to have two or more orthogonal radiation patterns with identical excitation frequency of the relevant ports. Therefore, the aforementioned sets can be used to acquire the pattern diversity. However, from obtained results, the set with the less practical implementation issues is selected to be excited. To perform the above-mentioned modal analysis, a specific method of moments (MoM) code has been developed and applied to identify different radiating modes. Two microstrip transmission lines were used as feeding parts so as to excite the suitable set of modes.
TL;DR: In this paper, a monopole-slot antenna with polarization diversity is proposed for wireless local area network (WLAN) applications, which achieves low mutual coupling due to the orthogonal modes of current distribution on the ground.
Abstract: A compact monopole-slot antenna with polarization diversity is proposed for wireless local area network (WLAN) applications. Dual polarization is provided by a ground-folded monopole and a slot cut from the folded ground. The total volume of the proposed antenna is only 50 × 16 × 16 mm3 (0.4 λ0 × 0.128 λ0 ×0.128 λ0). However, low mutual coupling is achieved due to the orthogonal modes of current distribution on the ground. A prototype of the proposed antenna is built and tested. The obtained results include the S parameters, radiation patterns and radiation gain. The results from our presentation match with the simulation and demonstrate an isolation better than -36 dB in the required band.
01 Oct 2012
TL;DR: In this paper, a matched multiband microstrip antenna intended to collect RF energy efficiently in commonly used portions of the selected cellular frequency spectrum including the ISM bands is proposed for high energy conversion efficiency.
Abstract: This paper covers the design, implementation and usage of a matched multiband microstrip antenna intended to collect RF energy efficiently in commonly used portions of the selected cellular frequency spectrum including the ISM bands. Multistage Schottky rectifier antenna (rectenna) array circuit is proposed for high energy conversion efficiency to improve battery life and portability. Design details for the multiband microstrip antenna prototype is presented.
TL;DR: In this paper, a multiband meandered square microstrip patch antenna with a metamaterial was designed to function in multiple bands in the frequency range 0.6-2.2 GHz.
Abstract: Magnetic properties can be imparted to a naturally nonmagnetic material by metallic inclusions. A multiband meandered square microstrip patch antenna loaded with such a metamaterial is reported. Metamaterials exhibit qualitatively new electromagnetic response functions that cannot be found in nature. The inclusion of these structures allows simultaneous operation over several frequencies. The antenna was designed to function in multiple bands in the frequency range 0.6–2.2 GHz. The antenna has eight working frequency bands and its centre frequencies are 670 MHz, 1185 MHz, 1293 MHz, 1747 MHz, 1909 MHz, 1999 MHz, 2063 MHz and 2134 MHz. The metamaterial also enhances the gain of the antenna, which is applicable for several wireless applications. Design results were obtained by a high frequency structure simulator which is used for simulating microwave passive components.
01 Sep 2012
TL;DR: A novel multi-band antenna of mobile phone with a metal frame, aiming to protect LCD in actual mobile phone, occupies almost 600 mm2 with little clearance, however, good performances of the proposed antenna will be obtained by using of this simple structure.
Abstract: A novel multi-band antenna of mobile phone with a metal frame has been proposed. The intrinsic slot between metal frame and the metal ground of the handset is taken as one part of the handset antenna, and the other part slot is etched at metal reinforcing plate, aiming to protect LCD (liquid crystal display) in actual mobile phone. Two slots are fed by a common microstrip line in series. The antenna occupies almost 600 mm2 with little clearance, however, good performances of the proposed antenna will be obtained by using of this simple structure. The measured results of the return loss, efficiency and radiation pattern are presented.
TL;DR: A tunable antenna pair for wireless transceivers using RF MEMS tunable capacitors is presented, which utilizes antenna frequency agility to cover a frequency tuning range corresponding to the PCS and IMT bands of the cellular systems, although the same concept can be extended to additional bands.
Abstract: A tunable antenna pair for wireless transceivers using RF MEMS tunable capacitors is presented. This design utilizes antenna frequency agility to cover a frequency tuning range from 1850 MHz to 2170 MHz (16%) corresponding to the PCS and IMT bands of the cellular systems, although the same concept can be extended to additional bands. Each antenna in the pair is designed to operate at the transmit and receive channels of the band, respectively, while the narrow impedance bandwidth of the single element provides built-in filtering between antennas. The level of isolation between elements is studied for several antenna arrangements depending on their relative orientation within the handset. High isolation levels can help in relaxing the duplexer specifications. A fabricated prototype is presented and measured to prove the concept and validate the design performance.