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WO2010092208A1 - Surface sélective en fréquence et plan conducteur magnétique artificiel à fréquences inférieures à 1ghz, et leurs utilisations - Google Patents

Surface sélective en fréquence et plan conducteur magnétique artificiel à fréquences inférieures à 1ghz, et leurs utilisations Download PDF

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Publication number
WO2010092208A1
WO2010092208A1 PCT/ES2010/000065 ES2010000065W WO2010092208A1 WO 2010092208 A1 WO2010092208 A1 WO 2010092208A1 ES 2010000065 W ES2010000065 W ES 2010000065W WO 2010092208 A1 WO2010092208 A1 WO 2010092208A1
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WO
WIPO (PCT)
Prior art keywords
plane
artificial magnetic
frequency
magnetic conductor
systems
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/ES2010/000065
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English (en)
Spanish (es)
Inventor
Fernando LAS HERAS ANDRÉS
Ma. Elena DE COS GÓMEZ
Mercedes FRANCO MARZÁBAL
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Universidad de Oviedo
Original Assignee
Universidad de Oviedo
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Universidad de Oviedo filed Critical Universidad de Oviedo
Publication of WO2010092208A1 publication Critical patent/WO2010092208A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/27—Adaptation for use in or on movable bodies
    • H01Q1/28—Adaptation for use in or on aircraft, missiles, satellites, or balloons
    • H01Q1/286—Adaptation for use in or on aircraft, missiles, satellites, or balloons substantially flush mounted with the skin of the craft
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
    • H01Q1/38—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith formed by a conductive layer on an insulating support
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
    • H01Q15/0006—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
    • H01Q15/0006—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices
    • H01Q15/0086—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices said selective devices having materials with a synthesized negative refractive index, e.g. metamaterials or left-handed materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
    • H01Q9/04—Resonant antennas
    • H01Q9/16—Resonant antennas with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole
    • H01Q9/28—Conical, cylindrical, cage, strip, gauze, or like elements having an extended radiating surface; Elements comprising two conical surfaces having collinear axes and adjacent apices and fed by two-conductor transmission lines
    • H01Q9/285—Planar dipole

Definitions

  • the present invention relates to a frequency selective surface and an artificial magnetic conductor plane at frequencies below 1 GHz.
  • the invention also relates to the uses of the frequency selective surface and the artificial magnetic conductor plane synthesized with it, in systems of communications, for the implementation of filters, such as mass plane for antennas and for labeling, and in radio frequency identification systems on metals, in the UHF band.
  • the invention is applicable in the sectors in which materials and devices are designed, produced, manufactured and / or used for radiofrequency identification, preferably on metals or in environments with the presence of metals, such as in hospital logistics, for example. airports, stations, in the manufacturing industry, transportation, automotive, food industry, metallurgical and manufacturing of industrial products, among others.
  • Radio frequency identification (RFID) systems are experiencing a great boom due to their applications in the identification, tracking, location or detection of a wide variety of objects and also of living beings (L. Boglione, IEEE Microwave Magazine, VoI. 8, No. 6, 2007, pp. 30-32; R. Das, P. Harrop. IDTECHEX 2008. RFID Forecasts, Players & Opportunities 2008-2018; S. Miles, S. Sarma, J. Williams Co-Editors, Cambridge University Press, RFID Technology and Applications. 2008; S. Miles, Auto-ID Research: Auto-ID-Development and Adoption - A Worldwide Perspective. 2008. Laboratory for Manufacturing Productivity. Massachusetts Institute of Technology (MIT); M. Stewart, USA DOD Logistic AIT Office, DLA Expo Workshop, 2005).
  • An RFID system is normally composed of three elements: the tag (tag or transponder), the reader (reader) and the data processing subsystem (middleware).
  • tag tag or transponder
  • reader reader
  • data processing subsystem middleware
  • a label that works by electromagnetic coupling is formed by an antenna and an integrated circuit or chip (K. Finkenzeller. Wiley, Chichester, 2004).
  • the labels are classified as active, passive and semi-passive depending on whether or not they incorporate a battery.
  • the material to which the label adheres should have a minimal effect on it, so that it works properly.
  • the antennas of the labels do not operate independently of the objects that are nearby, but they can degrade their radiation properties to a different degree.
  • the reading range of the labels and their stability change depending on the characteristics of the surface materials on which they are placed. Thus, for example, if the surfaces are made of dielectric materials, the reading range may decrease due to the displacement of the resonance frequency.
  • the radiation efficiency based on the electrical property of the surface materials.
  • antennas for RFID tags is subject to a number of restrictions, if the tags are intended to replace a massive labeling system such as the barcode at the object level. These restrictions are costly, since the antenna must be cheap; in size, so that the antenna footprint is small and thus be able to identify small objects; and of small thickness so that, for example, they are flexible.
  • PIFA inverted F-shaped antennas
  • foam-tuned dipoles are known.
  • microstrip patch antennas have a low bandwidth, need a non-negligible thickness and are usually fragile (brittle), eliminating the possibility of using them in flexible sticker type labels.
  • the inverted F-shaped flat antennas (PIFA) are smaller and have greater bandwidth, but still small for RFID radiofrequency identification. Attempts to increase bandwidth have led to complex structures that imply an increase in manufacturing difficulty and cost (M. Hirvonen, P. Pursula, K. Jaakkola, K. Laukkanen, Electron. Lett., Vol.40, pp 848-850, July 2004).
  • the thickness is still not negligible.
  • the PIFA antennas need at least a small metallization (shorting p ⁇ ate or shortingpin) lateral of connection of the radiating element with the plane of metallic mass, which makes them not suitable for flexible labels of type sticker because when folding the label, said Metallization could break easily.
  • the dipoles tuned to work at a height of a quarter of a wavelength at the frequency of interest on the mass plane require separating the dipole from the mass plane by means of a foam layer of the mentioned thickness, that is, of a quarter wavelength at the frequency of interest, which is not negligible at the frequencies of the UHF band.
  • FAT Tags Foam Attached Tags
  • Some designs are PIFA antennas that also incorporate foam (W. Choi et al, ETRI Journal, VoI 28, No. 2, April 2008).
  • the thickness is smaller than a quarter of a wavelength, it is still considerable (since layers of dielectric substrate and foam are usually sandwiched) for labeling small objects.
  • the greater the thickness of the foam layer the less suitable the design for a flexible or sticker type label is.
  • AMCs artificial magnetic conductors
  • AMCs artificial magnetic conductors
  • few designs of artificial magnetic conductors are known for frequencies in the range of 900 MHz to 1 GHz, such as that described in WO / 2003/107484, not serving the UHF band of European radiofrequency identification frequencies;
  • the scarce designs of these structures for frequencies of UHF bands other than the European ones are complex and difficult to manufacture, with nothing negligible thicknesses and large base cell size, which makes their use in the labeling of small objects impossible.
  • Another added disadvantage is that they have very small artificial magnetic conductor behavior bandwidths.
  • FSS refers to a frequency selective surface, which is understood as the surface constituted by the periodic repetition of a unit cell and designed to reflect or transmit electromagnetic waves with frequency discrimination.
  • AMC refers to artificial magnetic conductor. Until now, no perfect magnetic conductors (PMCs) have been discovered in Nature and therefore have to be synthesized.
  • PMCs perfect magnetic conductors
  • One possible way to synthesize an AMC is to place one or more FSS on a conducting plane. AMCs behave like PMCs over a certain frequency band, which is considered the AMC operating band.
  • Said band is centered on the resonance frequency of the AMC, at which the phase of the reflection coefficient in the FSS plane is null and has as lower and upper limits the frequencies for which said phase of the reflection coefficient takes the values + 90 ° and -90 ° respectively.
  • the AMC bandwidth in% is the difference between the upper and lower frequency limits of said AMC operating band divided by the center or resonance frequency and multiplied by 100.
  • Lambda ( ⁇ ) refers to the wavelength in free space at the resonant frequency of the structure.
  • metallic holes or also known as metallic connection paths or holes between layers of a circuit, refers to those that, through the substrate, serve to connect the periodic metallization of the FSS with the lower metallic mass plane added to constitute the AMC.
  • the present invention relates to a frequency selective surface (FSS) comprising a periodic metallization structure constituted by the repetition of the metallization of a unit cell on a dielectric substrate.
  • Said unit cell is of a size not exceeding ⁇ / 25, and the relative dielectric constant of the dielectric substrate takes values between 18 and 140.
  • it lacks metallized holes that cross the substrate, and the resonance frequency is less than or equal to 1 GHz.
  • ⁇ is the free space wavelength at the resonant frequency of the structure.
  • the invention also relates to the use of said FSS in communications systems.
  • an artificial magnetic conductor plane comprising at least one frequency selective surface (FSS), located on a conductor mass plane.
  • Said frequency selective surface (FSS) in turn comprises a periodic structure of metallizations constituted by the repetition of the metallization of a unit cell on a dielectric substrate.
  • Said unit cell is of a size not greater than ⁇ / 25, and with values of the relative dielectric constant of the dielectric substrate between 18 and 140, it lacks metallic holes that cross the substrate and its resonance frequency is less than or equal to 1 GHz.
  • the resonance frequency of the artificial magnetic conductor plane (AMC) is less than or equal to 1 GHz.
  • the thickness of the AMC is not more than ⁇ / 100.
  • the metallizations are copper. In another specific embodiment, the metallizations are silver.
  • the AMC comprises a single frequency selective surface on a conductive mass plane.
  • the resonance frequency is less than or equal to 1 GHz.
  • the thickness of the AMC is not more than ⁇ / 100.
  • the metallizations are copper.
  • the metallizations are silver.
  • Another aspect of the invention is the use of an artificial magnetic conductor plane (AMC) comprising at least one of said FSS located on a conductor mass plane with a resonance frequency less than or equal to 1 GHz., In communications systems .
  • AMC artificial magnetic conductor plane
  • AMC artificial magnetic conductive plane
  • the use in communications systems is as a ground plane for an antenna.
  • the use in communications systems is for the implementation of filters in said systems.
  • Another aspect of the invention is the use of an AMC comprising at least one of said frequency selective surfaces on a plane of conductive mass and where the resonance frequency is less than or equal to 1 GHz, and the thickness of the AMC is not greater than ⁇ / 100, in communications systems.
  • AMC artificial magnetic conductive plane
  • the use in communications systems is as a ground plane for an antenna.
  • the antenna is of a tag for metallic objects in radiofrequency identification systems.
  • the antenna is of a passive tag on metallic objects in radio frequency identification systems in the UHF band.
  • the use in communications systems is for the implementation of filters in said systems.
  • One of the advantages over the state of the art is to have achieved a frequency selective surface with a small basic cell, not exceeding ⁇ / 25, and thickness not exceeding ⁇ / 100, at frequencies below IGHz. This It enables a considerable reduction in the size and thickness of the artificial magnetic conductor plane and, consequently, in the label that contains it, allowing the identification of small objects in UHF bands internationally.
  • the design of this basic cell gives the artificial magnetic conductor plane a high bandwidth (between 4 and 6%), which is an important achievement in this frequency band, given the small size and thickness of the cell .
  • the use of the artificial magnetic conductive plane as a mass plane on which the tag antenna is located allows it to be isolated from the metal, thus achieving excellent performance on metallic objects, thereby solving one of the major problems that RFID is finding.
  • UHF bands for its massive development and implementation.
  • it implies an increase in the gain and the bandwidth of the antenna, with respect to other conventional mass planes, as well as a considerable reduction or suppression of the rear lobes of radiation and the decrease of the antenna size and with Tag it. Therefore, objects smaller than those allowed by the state of the art can be labeled.
  • the design is planar, with a single layer of dielectric substrate and which also does not incorporate metallic holes, it can be massively manufactured using common printed circuit techniques, which significantly reduces the manufacturing cost of both the frequency selective surface, of the artificial magnetic conductor plane and the label as a whole. These characteristics allow its implementation on flexible substrates, which does not happen with the current alternatives that incorporate metallic holes.
  • One of the advantages of the preferred embodiment of the design of the unit cell shown in Fig. 1 of the FSS is that its geometry has symmetry, which imposes less restrictions on the polarization of the antenna that is placed on the AMC with it. synthesized, thus facilitating the reading of the label and thereby increasing the possibilities of identification of objects.
  • the resonant frequency can be varied for values less than or equal to IGHz, by corresponding scaling of the unit cell, always not larger than ⁇ / 25, and / or by varying the relative dielectric constant ⁇ r of the substrate in the range between 18 and 140.
  • the scalability gives the design presented here great versatility. This advantage extends to all the uses mentioned for both the FSS and the AMC in communications systems, such as the implementation of filters.
  • the lower the frequency, getting a design of an FSS and a small AMC is a more important achievement. Due to the scalability property, the same geometric design achieved for a low RFID UHF frequency band, such as the European band, can be used in the higher RFID UHF frequency bands, such as the USA and Asian countries, reducing the size of the unit cell using the same dielectric substrate, or maintaining the size and reducing the relative dielectric constant ⁇ r of the substrate. This avoids the costs of carrying out a completely new design for each case.
  • the invention is applicable in those sectors in which frequency selective surfaces are designed, produced or used, such as in communications systems, for the implementation of filters, as a mass plane for antennas and for labeling, in identification systems. by radiofrequency on metals, in the UHF band or less than or equal to IGHz and especially in those systems that require small sizes, such as laptops.
  • one of the applications of the AMC of the present invention is its use as a ground plane for antennas at frequencies lower than or equal to IGHz due to the improvement in the antenna performance as the improvement of the directivity and radiation efficiency, as well as the decrease of the back lobes of radiation.
  • its use as a mass plane for antennas in passive labels in the UHF band for identification of metallic objects or in environments where there are metals is especially interesting.
  • its use in the European RFID UHF band since the assigned frequencies (866 to 869 MHz) are of lower value than the UHF RFID bands of countries such as the USA (902 to 928 MHz) and Asia / Pacific countries (950 to 956 MHz).
  • Fig. 1 corresponds to a top view of the geometry of the unit cell (Z) or basic cell designed with its constituent elements.
  • (X) indicates the metallization of the unit cell (Z)
  • (Y) indicates the dielectric substrate of said unit cell (Z)
  • Tl) and (T2) refer to the two types of chamfers (Tl) and (T2) in the metallization (X) of the unit cell (Z).
  • the symmetry of the unit cell (Z) according to the diagonal plane a-a ' is also shown in Fig. 1.
  • Fig. 3 represents a perspective view of an artificial magnetic conducting plane from the repetition of 3 x 9 unit cells (Z) whose geometry corresponds to that of Fig. 1, where (D) refers to the structure Periodic metallization of the FSS, (Y) refers to the dielectric substrate and (F) refers to the conductive mass plane.
  • Fig. 4 represents the variation of the phase of the reflection coefficient in degrees, ⁇ T> (°) measured on the periodic structure of metallizations of the FSS (D), as a function of frequency, f.
  • An artificial magnetic conductor plane was used as a ground plane for an antenna of a passive RFID tag in the European UHF band.
  • a single FSS was used on a plane of conductive mass (F).
  • the AMC in question consisted of a plane of conductive mass (F), a dielectric substrate (Y) on the plane of conductive mass (F) and a periodic structure of metallizations (D) constituted by the repetition of metallization (X) of a unit or basic cell (Z), on the dielectric substrate (Y).
  • silver was used in the periodic structure of metallizations (D).

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Astronomy & Astrophysics (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • General Physics & Mathematics (AREA)
  • Remote Sensing (AREA)
  • Aerials With Secondary Devices (AREA)
  • Waveguide Aerials (AREA)

Abstract

L'invention concerne une surface sélective en fréquence (FSS) qui comprend une structure périodique de métallisations (D) constituée par la répétition de la métallisation d'une cellule sur un substrat diélectrique (Y). L'invention concerne également un plan conducteur magnétique artificiel (AMC) qui comprend au moins une FSS, située sur un plan de masse conducteur (F). L'invention peut être utilisée dans des systèmes de communications, en particulier dans les systèmes de taille réduite, comme les systèmes portables, par exemple pour la mise en oeuvre de filtres ou comme plan de masse pour antennes. L'invention trouve un intérêt particulier pour une utilisation dans l'étiquetage passif dans des systèmes d'identification par radiofréquence dans les bandes UHF sur des métaux ou des environnements dans lesquels des métaux sont présents, notamment dans le domaine logistique pour les hôpitaux, aéroports, gares, dans l'industrie de la manufacture, les transports, l'automobile, l'industrie alimentaire et métallurgique, entre autres.
PCT/ES2010/000065 2009-02-13 2010-02-12 Surface sélective en fréquence et plan conducteur magnétique artificiel à fréquences inférieures à 1ghz, et leurs utilisations Ceased WO2010092208A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ES200900486A ES2342816B2 (es) 2009-02-13 2009-02-13 Superficie selectiva en frecuencia y plano conductor magnetico artificial a frecuencias inferiores a 1ghz, y sus usos.
ESP200900486 2009-02-13

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WO2010092208A1 true WO2010092208A1 (fr) 2010-08-19

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9842685B2 (en) * 2014-07-21 2017-12-12 Mitsubishi Electric Research Laboratories, Inc. Artificial magnetic structures for wireless power transfer

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004093244A2 (fr) * 2003-04-11 2004-10-28 The Penn State Research Foundation Surfaces pixelisees selectives en frequence pour plans de masse artificiels reconfigurables a conduction magnetique
WO2007114554A1 (fr) * 2006-04-04 2007-10-11 Electronics And Telecommunications Research Institute Structure de surface à forte impédance utilisant un conducteur magnétique artificiel, et son emploi dans une antenne et un dispositif électromagnétique
WO2008069459A1 (fr) * 2006-12-04 2008-06-12 Electronics And Telecommunications Research Institute Structure d'antenne d'étiquette doublet pouvant être montée sur des objets métalliques au moyen d'un conducteur magnétique artificiel pour identification sans fil et système d'identification sans fil utilisant la structure d'antenne d'étiquette doublet

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004093244A2 (fr) * 2003-04-11 2004-10-28 The Penn State Research Foundation Surfaces pixelisees selectives en frequence pour plans de masse artificiels reconfigurables a conduction magnetique
WO2007114554A1 (fr) * 2006-04-04 2007-10-11 Electronics And Telecommunications Research Institute Structure de surface à forte impédance utilisant un conducteur magnétique artificiel, et son emploi dans une antenne et un dispositif électromagnétique
WO2008069459A1 (fr) * 2006-12-04 2008-06-12 Electronics And Telecommunications Research Institute Structure d'antenne d'étiquette doublet pouvant être montée sur des objets métalliques au moyen d'un conducteur magnétique artificiel pour identification sans fil et système d'identification sans fil utilisant la structure d'antenne d'étiquette doublet

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"Antennas and Propagation Society International Symposium, 2008. AP-S 2008. IEEE, 05.07.2008", ISBN: 978-1-4244-20, article MCKINZIE W E ET AL.: "Experimental results of an AMC antenna fabricated with a magnetically- loaded elastomeric substrate", pages: 1 - 4 *
BARACCO, J.-M. ET AL.: "AMC Low Profile Wideband Reference Antenna for GPS and GALILEO Systems", IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, vol. 56, no. 8, August 2008 (2008-08-01), pages 2540 - 2547 *

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ES2342816B2 (es) 2011-04-20
ES2342816A1 (es) 2010-07-14

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