Classifications

• • 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
• • 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
  • H01Q9/30—Resonant antennas with feed to end of elongated active element, e.g. unipole
  • H01Q9/42—Resonant antennas with feed to end of elongated active element, e.g. unipole with folded element, the folded parts being spaced apart a small fraction of the operating wavelength
• • 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
• • 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
  • 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
  • H01Q5/378—Combination of fed elements with parasitic elements
• • 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
  • H01Q9/14—Length of element or elements adjustable
• • 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
  • H01Q9/14—Length of element or elements adjustable
  • H01Q9/145—Length of element or elements adjustable by varying the electrical length

Definitions

• the present invention relates to a low volume antenna intended to be used in particular but not exclusively in a portable radiotelephone.
• helix-shaped antennas which are most often mounted outside the radiotelephone housing. These antennas may have a relatively small dimension but they are arranged outside the housing to be associated with a ground plane which is arranged inside the radiotelephone housing.
• plate antennas of the PiFa type or similar in radiotelephones.
• These plate antennas which are essentially constituted by a ground plane and by a radiating plate, more generally a radiant element substantially parallel to the ground plane, also include a short-circuit connection between the radiant element and the ground plane as well. than an antenna supply generally at 50 Ohms but not exclusively and most often carried out using a microstrip line or coaxial connectors or connectors with parallel contacts whose characteristic impedance is close to 50 Ohms.
• the minimum distance between the radiant element and the ground plane is of the order of 7 to 10 mm, at least when the dielectric disposed between the radiant element and the ground plane is air.
• This thickness of the order of 7 to 10 mm is considered to be too great for the production of radiotelephones.
• Known plate antennas do not therefore meet the second condition stated above.
• An object of the present invention is to provide an antenna in particular usable in a portable radiotelephone which has a very small volume whose thickness is reduced.
• the antenna must be of an architecture which allows its use at least in two frequency bands.
• the antenna of very small volume for portable device comprises:
• the antenna being constituted by the two conductive surfaces substantially disposed on the same geometric surface mentioned above, the antenna can have a very reduced thickness which is either the thickness of the metal sheet in which its surfaces are cut , or the thickness of the flexible or non-flexible insulating substrate on which metallizations have been carried out. In fact, it is the connection that locally increases the thickness of this antenna.
• the second metallization which constitutes the radiant assembly of the antenna can be given a shape such that the antenna can operate in the ranges GSM 850 (USA), GSM 900 (Europe) and in the DCS 1800 (Europe) and PCS 1900 (USA) ranges.
• this antenna has a very wide band, for example of the order of 25% and is characterized by semi-independence with respect to the elements and components of the radiotelephone station.
• semi-independence we mean that the functioning of the antenna is not affected by the other components or elements of the device in which the antenna is mounted.
• the antenna is only disturbed by the presence, in its immediate vicinity, of a mass or a source of radiation ex: battery.
• the ground of the antenna must be supplied directly to the transceiver module in mass independent of the mass of the device.
• this antenna is mounted inside the device which it equips.
• this antenna may be advantageous to deposit it in the external mechanical member which constitutes the attachment of the device, in particular in the case of a radiotelephone.
• the antenna it is possible to manufacture the antenna by metallizing suitable geometries on a flexible insulating support which is initially plane. Then, this antenna can be fixed on a mechanical part or a component which is not planar, the flexible insulating support adapting to the particular shape of the mechanical part or of the component, the antenna then having the form of a left geometric surface.
• different antenna feed solutions are possible: a) asymmetrical
• FIG. 1A is a top view of an embodiment of the antenna
• Figure 1B is a vertical sectional view of the antenna of Figure 1A along line BB
• Figures 2A, 2B and 2C show first alternative embodiments of the first conductive surface
• Figures 2D and 2E show second alternative embodiments of the first conductive surface
• Figure 3 shows an alternative embodiment of the antenna in which it comprises active components
• Figure 3A shows curves illustrating the effect of the additional components
• Figure 4 is a top view of a preferred embodiment
• Figure 5 is a curve showing the operation of the antenna of Figure 4.
• the antenna is constituted by a first substantially planar conductive surface 10 constituted by a conductive strip 12 whose mean line 14 has substantially the shape of a rectangle with the exception of an opening 16 and whose width e is substantially constant.
• the length of the rectangle is equal to L and its width I.
• the conductive strip 12 internally defines an internal space 18.
• the antenna comprises a second substantially flat conductive surface 20 and substantially arranged in the same plane as the first conductive surface 10.
• the conductive surface 20 is constituted by a connection portion 22 and by a portion forming the radiant element of the antenna 24.
• the radiant element 24 is constituted by a first branch 26 connected to the connection zone 22 and by a second shorter branch 28.
• substantially planar it is meant that the conductive surfaces are planar with flatness defects close to the technology to achieve them.
• the conductive surfaces 10 and 20 are formed by metallizations produced on an insulating support 30.
• This insulating support 30 can be of any suitable nature, for example made of epoxy, or of the flexible insulating substrate type.
• the antenna produced can then be fixed on a non-planar support whose flexible support will conform to the shape.
• the antenna is constituted by the two conductive surfaces which are substantially arranged on the same geometric surface which may be left.
• connection area 22 of the second conductive surface 20 defines a point 32 of connection of the antenna conductor and the first conductive surface 10 includes an additional metallization 34 constituting a ground connection connectable to the independent mass transceiver module.
• the antenna may further comprise a connector 38 for effectively connecting the radiant element 24 to the antenna conductor and for connecting the ground point 34 to connected to the mass transceiver module independent of the device in which the antenna is integrated.
• the connector 38 can be a coaxial connector.
• the connection points 32 and 34 must be placed so as to have an impedance generally close to 50 Ohms in order to be connected to the central conductor and to the external conductor of the coaxial connector 38.
• the connector can also be a two-way two-way connector parallel contacts, the distance between the two contacts will be judiciously chosen to have an input characteristic impedance generally close to 50 Ohms.
• the antenna thus produced has a very reduced volume. Its length L and its width I can be respectively of the order of 28 to 33 mm and from 7 to 13 mm. Its thickness which is that of the insulating substrate 30 can be of the order of 0.1 mm. In fact, it is the thickness of the connector 38 and / or of the passive and / or active components which define in this direction the total size of the antenna. It should be added that the geometry of the first conductive surface 10 could be different because this conductive surface must be paired with the radiant element 24. However, it must effectively surround the internal space 18 with an opening whose length is very reduced compared to that of the conductive surface.
• Figures 2D and 2E show two other possible shapes for the first conductive surface 12.
• the first conductive surface 12a has a small side 13 which has a width greater than the other sides.
• the opening 16 'made in the second short side 13' does not have a middle position.
• the first conductive surface 12b has an irregular polygonal shape with six sides. Such a shape makes it possible to adapt the size of the antenna to the external environment while surrounding the second conductive surface constituting the radiating assembly.
• the conductive surfaces 10 and 20 were not constituted by. metallizations performed on an insulating substrate 30 and subsequently etched by any suitable method to define the particular shape of its two surfaces, but obtained by cutting a metal sheet. This metal sheet could have a thickness of the order of 0.2 to 0.3 mm. It would then of course be necessary to provide an insulating mechanical support to hold the two conductive surfaces relative to each other.
• Figures 2A, 2B and 2C show alternative embodiments of the first conductive surface.
• the second conductive surface may have a shape such that it defines two or more radiant elements, the dimensions of which correspond to two or more distinct frequency bands. In this case, the first conductive surface, having the shape of a conductive strip defining an open rectangle, cannot be granted with the two radiant elements.
• the first conductive surface further comprises a conductive extension 70 connected to the midpoint A of the small unopened side 72 of the strip 12.
• the extension 70 is arranged along one of the long sides of the strip. 12.
• the conductive extension 74 has an end 74a which is connected to an open end 76 of the strip 12.
• the first conductive surface comprises, in addition to the strip 12, two conductive extensions 78 and 80, the first end 78a, 80a of the extensions being connected to an open end 76, 76 'of the strip 12.
• FIG. 3 shows an exemplary embodiment of the antenna equipped with active components.
• the second conductive surface 20 which, in this embodiment, consists of two radiant elements 21 and 23 connected to the connection zone 25 which itself comprises the antenna contact area 32a.
• the antenna cable 90 with its central conductor 90a and its shielding 90b has also been shown there.
• the conductive strip 12 and the radiant element 23 are each provided with an active component constituted respectively by the varactors VI and V2 mounted in series on the corresponding metallization, the electrical power supply for the varactors is provided by the shield 90b of the antenna cable which feeds a variable continuous power source 92.
• the midpoint 92c of the power source 92 is connected to the cable shield, while the output terminals 92a and 92b of the source are used to power varactors VI and V2.
• the contact area 32a is connected to the central conductor 90a of the cable by a metallization 94 connected to the contact area 32a, passing through the opening 16, and by a blocking capacity C.
• the output terminal 92a of the source 92 is connected to metallization 94 by a stop choke Ll.
• the output terminal 92b of the source 92 is connected to the ground contact area 34a by a stop choke L2 and a conductive extension 96.
• the end 23a of the metallization 23 is connected to the ground contact area 34a by a stop choke L3 for the supply of the varactor V2 and the metallization 21 is connected to the conductive strip L4 for the supply of the varactor VI.
• FIG. 3A shows the transformation of a resonance from 890 MHz to 984 MHz, ie approximately 100 MHz by switching a passive element.
• this antenna being capable of operating in two frequency ranges corresponding in this particular case respectively to 4 bands GSM 850, GSM 900, DCS 1800 and
• the first conductive surface is formed by the conductive strip 12 ′, the mean line 14 ′ of which is a rectangle with the exception of the opening 16 ′, the substantially constant width e of this strip being equal to 1 mm in this embodiment.
• the ground contacts 34 'and antenna feed 42 are materialized by an additional surface metallization, for example gold for the use for example of spring contacts.
• the second conductive surface 20 ′ which is entirely disposed inside the internal space 18 ′ limited by the conductive strip 12 ′ constitutes a radiant assembly for the antenna, this radiant assembly defining in this particular case two radiant elements tuned on two separate frequency bands. More specifically, the conductive surface 20 'has a connection zone 40 provided with the antenna contact 42. The conductive surface 20' has a first portion 44 constituting a first radiant element for the highest frequency band, DCS or PCS. The radiant element 44 has the general shape of a U constituted by the two branches 46 and 48 connected at one of their ends by the conductive portion 50. The end 48a of the branch 48 is connected to the connection zone 40. The second radiant element 52, corresponding to the lowest frequency band, is tuned to the GSM 850 or 900 frequency band.
• This portion 52 comprises a first rectilinear branch 54 of which the end 54a is connected to the connection zone 40 and a second branch 56, the ends 54b and 56b are connected together by a portion of conductive surface 58 in the shape of a U whose axis x, x 'is orthogonal to the direction of the branches 54 and 56.
• the conductive strip 12 ′ is defined in such a way that it is in tune with the radiant elements 44.
• the conductive strip 12 ′ is completed by an extension 80 constituted by an additional metal strip, one end of which 80a is electrically connected to the center 82 the small unopened side of the strip 12 '.
• the other end 80b of the metallization 80 is free.
• the opening 16 'formed in the strip 12' has a length equal to 2 mm.
• this opening must have a very short length compared to that of the conductive strip 12 '.
• the opening has a length of less than 3 mm.
• the only electrical connection that can exist between the two conductive surfaces is a capacitive connection, an inductive connection or a combination of these two types of connection.
• FIG. 5 illustrates the operation of the antenna represented in FIG. 4. It shows the ROS (VSWR) as a function of the frequency F, and shows the importance of the bandwidth for the range
• GSM 850, 900 MHz and for the DCS, PCS range are examples of GSM 850, 900 MHz and for the DCS, PCS range.
• the thickness of the antenna it is equal to the thickness of the insulating substrate 30 'on which it is produced, except for the thickness of the connector which is associated with it.
• the antenna shown in FIG. 4 can be produced on a flexible insulating support.
• This antenna can be fixed on a non-planar surface of the device on which it is mounted.
• the geometric surfaces containing the two conductive surfaces are then left and the curves defining these surfaces are 3-dimensional curves.

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• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Support Of Aerials (AREA)
• Details Of Aerials (AREA)
• Waveguide Aerials (AREA)
• Variable-Direction Aerials And Aerial Arrays (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=32406397

Family Applications (1)

Country Status (8)

Families Citing this family (26)

Family Cites Families (7)

• 2002
  • 2002-12-23 FR FR0216516A patent/FR2849288A1/fr not_active Withdrawn
• 2003
  • 2003-05-09 US US10/434,124 patent/US6927731B2/en not_active Expired - Fee Related
  • 2003-12-22 EP EP03813933A patent/EP1576696A1/de not_active Withdrawn
  • 2003-12-22 AU AU2003303409A patent/AU2003303409A1/en not_active Abandoned
  • 2003-12-22 JP JP2004563302A patent/JP2006512003A/ja active Pending
  • 2003-12-22 KR KR1020057011785A patent/KR20050085870A/ko not_active Application Discontinuation
  • 2003-12-22 WO PCT/FR2003/003862 patent/WO2004059788A1/fr not_active Application Discontinuation
  • 2003-12-22 CN CNA2003801071771A patent/CN1729592A/zh active Pending

Non-Patent Citations (1)

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