WO2001015270A1 - A compact antenna for multiple frequency operation - Google Patents

A compact antenna for multiple frequency operation Download PDF

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Publication number
WO2001015270A1
WO2001015270A1 PCT/SG2000/000121 SG0000121W WO0115270A1 WO 2001015270 A1 WO2001015270 A1 WO 2001015270A1 SG 0000121 W SG0000121 W SG 0000121W WO 0115270 A1 WO0115270 A1 WO 0115270A1
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WO
WIPO (PCT)
Prior art keywords
antenna
substrate
comb
array
elements
Prior art date
Application number
PCT/SG2000/000121
Other languages
French (fr)
Inventor
Tat Soon Yeo
Original Assignee
National University Of Singapore
Leong, Mook, Seng
Kooi, Pang, Shyan
Yeo, Swee, Ping
Ooi, Ban, Leong
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 National University Of Singapore, Leong, Mook, Seng, Kooi, Pang, Shyan, Yeo, Swee, Ping, Ooi, Ban, Leong filed Critical National University Of Singapore
Publication of WO2001015270A1 publication Critical patent/WO2001015270A1/en

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Classifications

    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/12—Supports; Mounting means
    • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
    • H01Q1/242—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use
    • H01Q1/243—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use with built-in antennas
    • 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
    • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
    • H01Q5/30—Arrangements for providing operation on different wavebands
    • H01Q5/307—Individual or coupled radiating elements, each element being fed in an unspecified way
    • H01Q5/342—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes
    • H01Q5/357—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes using a single feed point
    • H01Q5/364—Creating multiple current paths
    • H01Q5/371—Branching current paths
    • 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
    • H01Q9/06—Details
    • H01Q9/065—Microstrip dipole antennas

Definitions

  • the present invention relates generally to the field of antenna design and in particular the invention relates to antennas designed to operate in two or more distinct frequency bands, and more particularly, to antennas formed as a thin conductor located on a non-conductive substrate material.
  • dual-frequency antennas There are several types of dual-frequency antennas listed in patent literature. However, these are either bulky (of the reflector type), non-planar (multi-dielectric layer microstrip patch type), or with conductor printed on both sides of the plastic substrate material. It is clear that the first type (bulky reflector type) is not suitable for mobile communication application. The second (multilayer microstrip patch), on the other hand, occupies space and is thus not suitable for use when flush-mounting of antennas is essential. Finally, the third type (conductors on both side of substrate) of antenna is not suitable for mounting against conductive materials like reinforced concrete or aluminium false ceiling.
  • the present invention consists in an antenna for operation in a plurality of distinct frequency bands, the antenna comprising an array of conductive elements constructed on a sheet of substrate material, the array having two generally comb- shaped structures, the comb-shaped structures each including a plurality of parallel antenna elements extending from a perpendicularly extending conductor forming a back of the comb-shaped structure, the parallel elements having lengths selected to suit the frequencies and bandwidths of operation, and the comb- shaped structures being located with the back conductors of adjacent comb- shaped structures located adjacent and parallel to one another, and the respective parallel elements projecting outwardly from the back conductors.
  • the array of conductive elements is symmetrical about a line located between and parallel to the back conductors of each comb-shaped structure, and includes at least one element in each comb-shaped structure for each frequency band in which the antenna operates.
  • the antenna is a two-band antenna, comprising three elements on each comb structure, one element of each comb structure being for one band of operation of the antenna, and the remaining elements of each comb structure being for the other band of operation of the antenna.
  • the substrate may either be a flat and rigid or semi-rigid support, such as a sheet of fibreglass printed circuit board material, a shaped rigid or semi-rigid support, such as moulded plastic case or other suitable non-conductive surface, or as a flexible sheet, such as a thin sheet or film of plastics material, or a sheet of similar non-conductive material.
  • a flat and rigid or semi-rigid support such as a sheet of fibreglass printed circuit board material, a shaped rigid or semi-rigid support, such as moulded plastic case or other suitable non-conductive surface, or as a flexible sheet, such as a thin sheet or film of plastics material, or a sheet of similar non-conductive material.
  • the conductors are formed on only one side of the substrate material and are preferably applied by printing or screen printing, although other methods of formation such as laminating, gluing or forming a conductive film and selectively etching are also possible.
  • Preferred embodiments of the invention provide an antenna for dual- frequency mobile communication systems that is compact, light-weight, of low cost, and easy to produce.
  • the antenna can be mounted flat against a conductive ceiling, or wall surface (such as concrete or metal), the back frame of an art painting or other decorative material, or can be made to conform to the shape of other background material (e.g., curved pillars, etc).
  • Figure 1 illustrates the general arrangement of an antenna according to an embodiment of the present invention in plan view
  • Figure 2 is an edge view of the antenna of Figure 1;
  • Figure 3 is an example of the antenna of Figure 1 showing dimensions required to achieve a particular set of frequency responses
  • Figure 4 illustrates a performance curve of the antenna of Figure 1.
  • FIG. 1 shows the general arrangement of embodiments of the invention in plan view.
  • An antenna array is formed as two back to back comb-shaped conductors 13, 14, fabricated on a dielectric substrate 12.
  • the conductors can be made of copper, aluminium, gold or any other appropriate conducting material.
  • the dielectric substrate can be rigid or flexible.
  • the material can be ceramic, plastics, or any other appropriate non-conductive material.
  • the substrate thickness is not restricted, but is used as design parameter.
  • the dimensions 15, 16, 17 of the comb-shaped conductors 13, 14 are determined by the centre frequencies of the frequency bands in which the antenna operates as well as the associated bandwidths of the multi-frequency operation.
  • the spacing 18 between the two comb shaped conductors is determined by the impedance matching requirements of the antenna.
  • the antenna is fed via the feed points 19, 20 as shown in Figure 1.
  • the feeding network while it is not part of the present invention, should be designed in conjunction with the antenna to meet specific application requirements.
  • Figure 2 shows the side view of the antenna viewed through line A- A in figure 1.
  • the substrate can be any plastics or ceramic material, depending on frequency and size requirements. However, the cheapest and most commonly available substrate is the FR4 fibreglass substrate used commercially as printed circuit board.
  • the antenna metallisation is in the shape of two comb-shaped structures 13, 14 facing back-to-back.
  • the number of fingers 23, 24, 25, 26, 27, 28 employed depends on the gain and radiation pattern requirements.
  • an antenna is designed to have a narrow-band high-gain operation at frequency f_, and a broad-band low-gain operation at frequency f 2 , where f 2 > fi.
  • f_ narrow-band high-gain operation
  • f 2 broad-band low-gain operation
  • Typical dimensions of a dual-band antenna constructed are given in Fig. 3.
  • the antenna is constructed on a 1.56 mm thick FR4 substrate 12 (see Figure 1) of dimensions 130 mm x 880 mm.
  • the length of the radiating elements (208 mm and
  • ⁇ r is the dielectric constant of the substrate.
  • the width 31 of the metallisation is chosen such that the characteristic impedance of the strip (metallisation) is approximately 50 ⁇ via the following equation:
  • the spacing 33 between the two groups of radiators (20 mm) is chosen to be slightly larger than the width of the strip (metallisation 19 mm).

Abstract

An antenna intended for use in mobile communication systems is constructed as a pair of conductive comb-shaped structures on a flat rigid substrate or a flexible sheet of substrate material. It can be designed to operate in two or more distinct frequency bands according to the specifications of the communication systems.

Description

A COMPACT ANTENNA FOR MULTIPLE FREQUENCY OPERATION
Field of the invention
The present invention relates generally to the field of antenna design and in particular the invention relates to antennas designed to operate in two or more distinct frequency bands, and more particularly, to antennas formed as a thin conductor located on a non-conductive substrate material.
Background of the mvention
Due to the developments in wireless communications, multiple radio mobile systems operating at different frequencies are gaining increasing popularity. To reduce production cost and space occupied by the antennas, it is desirable to have, for signal reception, a simple dual-frequency antenna in lieu of two separate antennas.
There are several types of dual-frequency antennas listed in patent literature. However, these are either bulky (of the reflector type), non-planar (multi-dielectric layer microstrip patch type), or with conductor printed on both sides of the plastic substrate material. It is clear that the first type (bulky reflector type) is not suitable for mobile communication application. The second (multilayer microstrip patch), on the other hand, occupies space and is thus not suitable for use when flush-mounting of antennas is essential. Finally, the third type (conductors on both side of substrate) of antenna is not suitable for mounting against conductive materials like reinforced concrete or aluminium false ceiling.
Summary of the invention
The present invention consists in an antenna for operation in a plurality of distinct frequency bands, the antenna comprising an array of conductive elements constructed on a sheet of substrate material, the array having two generally comb- shaped structures, the comb-shaped structures each including a plurality of parallel antenna elements extending from a perpendicularly extending conductor forming a back of the comb-shaped structure, the parallel elements having lengths selected to suit the frequencies and bandwidths of operation, and the comb- shaped structures being located with the back conductors of adjacent comb- shaped structures located adjacent and parallel to one another, and the respective parallel elements projecting outwardly from the back conductors.
Preferably, the array of conductive elements is symmetrical about a line located between and parallel to the back conductors of each comb-shaped structure, and includes at least one element in each comb-shaped structure for each frequency band in which the antenna operates. There may be more than one element of each comb-shaped structure provided for a particular band of operation in which case the number of parallel elements provided in each comb- shaped structure in respect of that band, is a function of the required bandwidth and gain of the antenna in the band.
Preferably, the antenna is a two-band antenna, comprising three elements on each comb structure, one element of each comb structure being for one band of operation of the antenna, and the remaining elements of each comb structure being for the other band of operation of the antenna.
The substrate may either be a flat and rigid or semi-rigid support, such as a sheet of fibreglass printed circuit board material, a shaped rigid or semi-rigid support, such as moulded plastic case or other suitable non-conductive surface, or as a flexible sheet, such as a thin sheet or film of plastics material, or a sheet of similar non-conductive material.
In preferred embodiments, the conductors are formed on only one side of the substrate material and are preferably applied by printing or screen printing, although other methods of formation such as laminating, gluing or forming a conductive film and selectively etching are also possible.
Preferred embodiments of the invention provide an antenna for dual- frequency mobile communication systems that is compact, light-weight, of low cost, and easy to produce. The antenna can be mounted flat against a conductive ceiling, or wall surface (such as concrete or metal), the back frame of an art painting or other decorative material, or can be made to conform to the shape of other background material (e.g., curved pillars, etc).
Brief Description of the Drawings
An embodiment of the invention will now be described by way of example, with reference to the accompanying drawings in which:
Figure 1 illustrates the general arrangement of an antenna according to an embodiment of the present invention in plan view;
Figure 2 is an edge view of the antenna of Figure 1;
Figure 3 is an example of the antenna of Figure 1 showing dimensions required to achieve a particular set of frequency responses; and
Figure 4 illustrates a performance curve of the antenna of Figure 1.
Detailed Description of Preferred Embodiments of the Invention
Referring to the accompanying drawings, embodiments of the invention are illustrated which serve to explain the construction of antennas 11 built generally in accordance with the invention. Figure 1 shows the general arrangement of embodiments of the invention in plan view. An antenna array is formed as two back to back comb-shaped conductors 13, 14, fabricated on a dielectric substrate 12. The conductors can be made of copper, aluminium, gold or any other appropriate conducting material. The dielectric substrate can be rigid or flexible. The material can be ceramic, plastics, or any other appropriate non-conductive material. The substrate thickness is not restricted, but is used as design parameter. The dimensions 15, 16, 17 of the comb-shaped conductors 13, 14 are determined by the centre frequencies of the frequency bands in which the antenna operates as well as the associated bandwidths of the multi-frequency operation. The spacing 18 between the two comb shaped conductors, on the other hand, is determined by the impedance matching requirements of the antenna. The antenna is fed via the feed points 19, 20 as shown in Figure 1. The feeding network, while it is not part of the present invention, should be designed in conjunction with the antenna to meet specific application requirements.
Figure 2 on the other hand, shows the side view of the antenna viewed through line A- A in figure 1.
Embodiments of the invention exhibit a planar antenna with metallisation
13, 14 on only one side of the substrate 12. The substrate can be any plastics or ceramic material, depending on frequency and size requirements. However, the cheapest and most commonly available substrate is the FR4 fibreglass substrate used commercially as printed circuit board.
Referring now to Figure 3 which is a specific example of the generalised design of Figure 1, the antenna metallisation is in the shape of two comb-shaped structures 13, 14 facing back-to-back. The number of fingers 23, 24, 25, 26, 27, 28 employed depends on the gain and radiation pattern requirements. For example, as illustrated in Figure 3, an antenna is designed to have a narrow-band high-gain operation at frequency f_, and a broad-band low-gain operation at frequency f2, where f2 > fi. Thus, in each comb shaped structure 13, 14 two elements 23, 24, 26, 27 are needed at fi while only one element 25, 28 is needed at f2, as a greater number of elements implies narrower-band and higher gain. The operation of the antenna can thus be extended to three or more bands of operations and the gain at each individual band can be adjusted by varying the number of elements resonating in that band.
Typical dimensions of a dual-band antenna constructed are given in Fig. 3.
The antenna is constructed on a 1.56 mm thick FR4 substrate 12 (see Figure 1) of dimensions 130 mm x 880 mm. The length of the radiating elements (208 mm and
417 mm) are chosen to be approximately one quarter of the wavelength at the dual frequencies as follow:
160 MHz/c/Vεeff/4 « 417 mm
290 MHz/c/Vεeff/4 » 208 mm where c is the speed of light and εe_f is the effective dielectric constant of the microstrip conductor given by:
Figure imgf000006_0001
where h is the thickness of the substrate = 1.56 mm, w is the width of the metallisation = 19 mm, and εr is the dielectric constant of the substrate.
The width 31 of the metallisation is chosen such that the characteristic impedance of the strip (metallisation) is approximately 50 Ω via the following equation:
Figure imgf000006_0002
The spacing 32 between the two low-frequency radiating elements (s = 10 mm) and the difference between the length of these two elements (Δ = 417 mm - 398 mm = 19 mm) such that
cos(ks/ A c X) + l ύniksl c X) -
Figure imgf000006_0003
where Y = (ZQ cot(2πfΔΛ/(εeff)/c)), f is the frequency of operation and c is the speed of light.
The spacing 33 between the two groups of radiators (20 mm) is chosen to be slightly larger than the width of the strip (metallisation 19 mm).
The spacing between the two Comb- shapes 13, 14 (sp = 2 mm) is chosen such that the characteristic impedance of the slot thus formed has a 50 Ω impedance for easy matching with the coaxial cable feed to be connected to it.
Thus: 50 * 113.19 - 53.551og(εr) + 1.25(sp/h){114.59-51.881og(εr)} + 20{(sp/h)-0.2}{l - (sp/h)} - {0.15 + 0.231og(εr) + (sp/h)[-0.79 + 2.071og(εr)]}{10.25 - 51og(εr) + (sp/h){2.1 - 1.421og(εr)} - 100(hf/c)}2
The performance of such an antenna is given by the impedance graph in Fig. 4, from which it can be seen that the objectives of a narrow-band high-gain radiation at about 150 - 170 MHz and a broad-band low-gain radiation at about 280 - 300 MFIz have been well achieved.
It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

Claims:
1. An antenna for operation in a plurality of distinct frequency bands, the antenna having an array of conductive elements constructed on a sheet of substrate material, the array comprising two generally comb-shaped structures, the comb-shaped structures each including a plurality of parallel antenna elements extending from a perpendicularly extending conductor forming a back of the comb-shaped structure, the parallel elements having lengths selected to suit the frequencies and bandwidths of operation, and the comb-shaped structures being located with the back conductors of adjacent comb-shaped structures located adjacent and parallel to one another, and the respective parallel elements projecting outwardly from the back conductors.
2. The antenna as claimed in claim 1, wherein the array of conductive elements is symmetrical about a line located between and parallel to the back conductors of each comb-shaped structure.
3. The antenna as claimed in claim 1, wherein the array of conductive elements includes at least one element in each comb-shaped structure for each frequency band in which the antenna operates.
4. The antenna as claimed in claim 1, wherein, for each band of operation of the antenna, the number of parallel elements provided in each comb-shaped structure in respect of that band, is a function of the required bandwidth and gain of the antenna in the band.
5. The antenna as claimed in claim 1, wherein, the antenna is a two-band antenna, comprising three elements on each comb structure, one element of each comb structure being for one band of operation of the antenna, and the remaining elements of each comb structure being for the other band of operation of the antenna.
6. The antenna as claimed in claim 5, wherein the array of conductive elements is formed on only one side of the substrate material.
7. The antenna as claimed in claim 6, wherein the array of conductive elements is applied to the substrate by printing.
8. The antenna as claimed in claim 6, wherein the array of conductive elements is applied to the substrate by screen printing.
9. The antenna as claimed in claim 6, wherein the array of conductive elements is applied to the substrate by laminating the conductive array to the substrate.
10. The antenna as claimed in claim 6, wherein the array of conductive elements is applied to the substrate by gluing the conductive array to the substrate.
11. The antenna as claimed in claim 6, wherein the array of conductive elements is applied to the substrate by forming a conductive film bonded to the substrate and selectively etching to pattern the antenna into the film.
12. The antenna as claimed in claim 8, wherein the substrate is a flat, rigid or semi-rigid structure, with a non-conductive surface.
13. The antenna as claimed in claim 8, wherein the substrate is fibreglass printed circuit board material.
14. The antenna as claimed in claim 8, wherein the substrate is a shaped rigid or semi-rigid structure, with a non-conductive surface.
15. The antenna as claimed in claim 8, wherein the substrate is a moulded plastic structure.
16. The antenna as claimed in claim 8, wherein the substrate is a sheet or film of non-conductive flexible material.
17. The antenna as claimed in claim 8, wherein the substrate is a thin sheet or film of plastics material.
PCT/SG2000/000121 1999-08-24 2000-08-22 A compact antenna for multiple frequency operation WO2001015270A1 (en)

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SG9904109A SG90061A1 (en) 1999-08-24 1999-08-24 A compact antenna for multiple frequency operation

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2823909A1 (en) * 2001-04-23 2002-10-25 Framatome Connectors Int Three band mobile telephone antenna block having radiation zone/transition zone superimposed/metallic return electrically connected with transition zone width progressively/autonomously increasing along propagation direction.
WO2005053092A1 (en) * 2003-11-24 2005-06-09 Sandbridge Technologies, Inc. Modified printed dipole antennas for wireless multi-band communication systems
EP1754282A1 (en) * 2004-06-03 2007-02-21 Sandbridge Technologies, Inc. Modified printed dipole antennas for wireless multi-band communication systems
WO2009029520A1 (en) * 2007-08-27 2009-03-05 Rambus Inc. Antenna array with flexible interconnect for a mobile wireless device
CN101901959A (en) * 2009-05-27 2010-12-01 卡西欧计算机株式会社 Multiband planar antenna and electronic equipment
US7928920B2 (en) 2007-05-17 2011-04-19 Casio Computer Co., Ltd. Film antenna and electronic equipment
US8081124B2 (en) 2007-12-27 2011-12-20 Casio Computer Co., Ltd. Planar monopole antenna and electronic device
US8111200B2 (en) 2008-05-29 2012-02-07 Casio Computer Co., Ltd. Planar antenna and electronic device
US8941541B2 (en) 1999-09-20 2015-01-27 Fractus, S.A. Multilevel antennae

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JPH05347509A (en) * 1992-06-15 1993-12-27 Matsushita Electric Works Ltd Print antenna
EP0342175B1 (en) * 1988-05-10 1996-03-20 COMSAT Corporation Dual-polarized printed circuit antenna having its elements, including gridded printed circuit elements, capacitively coupled to feedlines

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DE3613258A1 (en) * 1986-04-19 1987-10-22 Licentia Gmbh Semiconductor substrate with at least one monolithically integrated circuit
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Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9362617B2 (en) 1999-09-20 2016-06-07 Fractus, S.A. Multilevel antennae
US9054421B2 (en) 1999-09-20 2015-06-09 Fractus, S.A. Multilevel antennae
US8941541B2 (en) 1999-09-20 2015-01-27 Fractus, S.A. Multilevel antennae
US9761934B2 (en) 1999-09-20 2017-09-12 Fractus, S.A. Multilevel antennae
US10056682B2 (en) 1999-09-20 2018-08-21 Fractus, S.A. Multilevel antennae
US9240632B2 (en) 1999-09-20 2016-01-19 Fractus, S.A. Multilevel antennae
US8976069B2 (en) 1999-09-20 2015-03-10 Fractus, S.A. Multilevel antennae
US9000985B2 (en) 1999-09-20 2015-04-07 Fractus, S.A. Multilevel antennae
FR2823909A1 (en) * 2001-04-23 2002-10-25 Framatome Connectors Int Three band mobile telephone antenna block having radiation zone/transition zone superimposed/metallic return electrically connected with transition zone width progressively/autonomously increasing along propagation direction.
US7034769B2 (en) 2003-11-24 2006-04-25 Sandbridge Technologies, Inc. Modified printed dipole antennas for wireless multi-band communication systems
WO2005053092A1 (en) * 2003-11-24 2005-06-09 Sandbridge Technologies, Inc. Modified printed dipole antennas for wireless multi-band communication systems
EP1754282A4 (en) * 2004-06-03 2008-04-02 Sandbridge Technologies Inc Modified printed dipole antennas for wireless multi-band communication systems
EP1754282A1 (en) * 2004-06-03 2007-02-21 Sandbridge Technologies, Inc. Modified printed dipole antennas for wireless multi-band communication systems
US7928920B2 (en) 2007-05-17 2011-04-19 Casio Computer Co., Ltd. Film antenna and electronic equipment
WO2009029520A1 (en) * 2007-08-27 2009-03-05 Rambus Inc. Antenna array with flexible interconnect for a mobile wireless device
US8374558B2 (en) 2007-08-27 2013-02-12 Rambus Inc. Antenna array with flexible interconnect for a mobile wireless device
US8081124B2 (en) 2007-12-27 2011-12-20 Casio Computer Co., Ltd. Planar monopole antenna and electronic device
US8111200B2 (en) 2008-05-29 2012-02-07 Casio Computer Co., Ltd. Planar antenna and electronic device
US8400364B2 (en) 2009-05-27 2013-03-19 Casio Computer Co., Ltd. Multiband planar antenna and electronic equipment
EP2262054A1 (en) * 2009-05-27 2010-12-15 Casio Computer Co., Ltd. Multiband planar antenna and electronic equipment
CN101901959A (en) * 2009-05-27 2010-12-01 卡西欧计算机株式会社 Multiband planar antenna and electronic equipment

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