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
  • 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
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/52—Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure
  • H01Q1/521—Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure reducing the coupling between adjacent antennas
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q13/00—Waveguide horns or mouths; Slot antennas; Leaky-waveguide antennas; Equivalent structures causing radiation along the transmission path of a guided wave
  • H01Q13/08—Radiating ends of two-conductor microwave transmission lines, e.g. of coaxial lines, of microstrip lines
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q13/00—Waveguide horns or mouths; Slot antennas; Leaky-waveguide antennas; Equivalent structures causing radiation along the transmission path of a guided wave
  • H01Q13/10—Resonant slot antennas
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q21/00—Antenna arrays or systems
  • H01Q21/28—Combinations of substantially independent non-interacting antenna units or systems
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q23/00—Antennas with active circuits or circuit elements integrated within them or attached to them
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
  • H01Q3/24—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching
• • 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
  • H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
  • H01Q9/0421—Substantially flat resonant element parallel to ground plane, e.g. patch antenna with a shorting wall or a shorting pin at one end of the element
• • 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

Definitions

• the present invention relates to an antenna system with diversity of order 2. It also relates to a wireless communication device card comprising such an antenna system.
• WIFI-type wireless communication devices In order to overcome these fluctuation problems in the received signals, it is customary to use diversity techniques.
• One of the widely used solutions in WIFI-type wireless communication devices is to have two receiving antennas and to switch between one or the other of these antennas in order to choose the best one. To ensure good diversity, it is therefore necessary that the two antennas are completely decorrelated. As a result, the antennas must be sufficiently spaced apart from each other.
• the most commonly used systems in WIFI devices consist of two external antennas dipole type.
• This solution has the advantage of easy integration since the antennas are then connected to the wireless card by coaxial flexible cables.
• the cost of this solution is relatively high.
• the antenna being an external element, it is fragile and can be easily destroyed or damaged.
• the present invention relates to a very compact second order diversity antenna system, easily integrable on an electronic card for wireless communication apparatus and having significant decorrelating properties.
• the present invention thus relates to a system of antenna of diversity of order 2 comprising, on the same substrate, first and second radiating elements positioned on two adjacent sides of the substrate near the periphery of said substrate, characterized in that, the substrate comprising a metallization plane, the first and second radiating elements each consist of an inverted type F antenna printed on the metallization plane of the substrate, the first and second radiating elements being positioned on the substrate at the angle formed by the two adjacent sides and being connected to each other at their end connected to the metallization plane.
• the invention thus defined has the form of an arrowhead (or "Arrowhead" in English).
• the inverted type F antenna is etched in the metallization plane.
• the inverted type F antenna is etched in at least two metallization planes of the substrate, each metal plane of the substrate thus etched and forming the body or strand of the antenna F-inverted being connected to each other via vias or metallized holes.
• the inverted type F antenna is constituted by a conductive strand parallel to one side of the substrate, the conductive strand being extended by an end portion connected to the metallization plane of the substrate, the antenna being connected to a feed line adapted perpendicular to the conductive wire.
• the resonant frequency of the conductive strand is given by the relation:
• A.Fres. ⁇ ⁇ eff where c represents the speed of light in a vacuum, ⁇ and f the effective permittivity of the propagation medium, F res the resonance frequency, D1 the length of the conducting strand between its free end and the point of connection with the supply line and H the height between the conductive strand and the metallization plane of the substrate.
• a slot is made at their ends connected to the metallization plane.
• the length of this slot can be chosen so that its resonant frequency corresponds to that of the strands of the antenna. This makes it possible to obtain an enlargement of the operating band of the antenna.
• the present invention also relates to an electronic card for a wireless communication device provided with an antenna system with diversity of order 2 as described above.
• Figure 1a is a partial perspective view of a first embodiment of a system according to the present invention and Figure 1b is a very schematic representation of the substrate used.
• FIG. 2 represents the various adaptation and isolation curves of the system of FIG. 1.
• FIGS. 3 and 4 respectively represent the radiation patterns obtained by exciting one or the other of the antennas of the system of FIG. 1.
• Figure 5 is a partial perspective view of another embodiment of a system according to the present invention.
• Figure 6 shows the adaptation and isolation curves of the system of Figure 5.
• Fig. 7 is a partial perspective view of a third embodiment of the present invention.
• FIG. 8 represents the adaptation and isolation curves of the embodiment of FIG. 7.
• FIGS. 9 and 10 represent the radiation patterns obtained by exciting one or the other of the antennas of the system represented in FIG. 7.
• Fig. 11 shows a partial perspective view of another embodiment of a system according to the present invention.
• FIG. 12 represents the various adaptation and isolation curves of the system of FIG. 11.
• Figures 13 and 14 show the radiation patterns obtained by exciting one or the other of the antennas of the system of Figure 11.
• FIG. 15 represents the adaptation and isolation curves of an antenna system according to the embodiment of FIG. 11 in which the width of the slot has been optimized.
• Fig. 16 is a partial perspective view of yet another embodiment of an antenna system according to the present invention.
• antennas 3 and 4 of the inverted F type were produced on a substrate 1 provided at least on its upper face with a conductive layer forming a metallization plane or ground plane 2, two antennas 3 and 4 of the inverted F type were produced. These antennas 3 and 4 are made by etching the ground plane 2 along the periphery of the substrate 1 so that the antennas 3 and 4 are perpendicular to each other while being connected by their ends forming a mass. In this configuration, the antenna system is in the form of an arrowhead.
• the antenna 3 which has a total length L and is positioned along an edge of the substrate 1 comprises a conductive strand having a first portion 30 of length D1 and a second part 31 of length D2.
• the portion 31 is extended by a portion 32 forming mass which is connected to the ground plane 2.
• the two parts 30, 31 are fed by a supply line 33 perpendicular to the conductive strand at the junction point of the parts 30, 31.
• This power line 33 ends with a port 34 and is adapted to 50 ⁇ .
• the inverted antenna 4 comprises a conductive strand having a first portion 40 extending through a second portion 41 which is extended by a mass portion 42. This portion 42 is connected to the ground portion 32 of the antenna 3 at an outer corner of the substrate.
• the parts 40, 41 are fed by a power supply line adapted to 50 ⁇ connected to the port 44.
• the resonance frequency of antennas 3 or 4 is obtained by the following equation:
• D1 represents the length of the portions 30 or 40 of the conductive strand
• ⁇ represents the height or dimension between the ground plane 2 and the conducting strand
• c represents the speed of the light in the vacuum
• ⁇ e ff represents the effective permittivity of the propagation medium
• F res represents the resonant frequency of the conductive strands.
• the dimension D2 of the portion 31 or 41 is chosen to play on the input impedance of the resonant portion 30 or 40 of the conductive strand.
• an increase (respectively a reduction) of D2 will have the effect of reducing (respectively increasing) the input impedance of the resonant strand.
• the mass portions 32 and 42 are connected to the ground plane. These parts have a length D3 whose value constitutes a degree of freedom to integrate the antenna system to an electronic card. Indeed, this current-free portion can receive fixing studs or other elements, even metal, allowing the integration of the card and the mechanical strength of the assembly.
• a 3D simulation was performed using a commercial electromagnetic simulator based on the finite element method known as HFSS Ansoft. This simulation was made using a multilayer FR4 substrate having a total thickness of 1.6 mm and a permittivity ⁇ r of 4.4.
• the stack of the substrate consists of a 4-layer FR4 substrate comprising 2 outer layers of a material known under the name Prepreg of 254 ⁇ m in thickness and an inner layer of FR4 of 889 ⁇ m. thick.
• the interface between the 3 substrate layers consists of 2 copper inner layers of 35 ⁇ m thick.
• the 2 outer conductive layers or metallization plane are made with copper of 17.5 .mu.m.
• the feed line is defined on the upper layers 1 for the signal and ground plane 2 for the mass.
• the Arrowhead is metallized over the entire thickness of the substrate, as well as for the ground plane.
• the antenna system of the F-inverted type as represented in FIG. 1 has the following dimensions:
• a system of this type operates in the 2.4 GHz to 2.5 GHz frequency band.
• the two F-inverted antennas are identical.
• the two antennas 3 and 4 may be of different length, so as to operate on different frequency bands.
• Arrowhead the direction of the arrowhead
• FIGS. 5 and 6 A variant embodiment of an antenna system in accordance with the present invention will now be described with reference to FIGS. 5 and 6.
• two antennas of the F-inverted type 3 ', 4' are produced by etching the metallization of a substrate 1 provided with a ground plane 2.
• the antenna system represented by FIG. FIG. 5 shows, for each antenna 3 'and 4', a ground portion 32 ', 42' whose length D3 has been reduced.
• a structure of this type has been simulated, as mentioned above, taking for D3 a value of 10 mm.
• FIGS. 7 to 10 another embodiment of an antenna system according to the present invention.
• the antennas 3 and 4 of the F-inverted type are identical to the antennas of FIG. 1.
• FIG. 7 only a part of the ground plane 2 'deposited on the whole of the substrate 1 has been hollowed out.
• a system of this type has been simulated using a device as mentioned above.
• the distance e between the ends of the strands and the ground plane 2 ' is 7 mm.
• FIG. 9 the diversity of the diagrams is maintained, as can be seen in the diagrams of FIGS. 9 and 10 respectively representing the radiation of antenna 3, FIG. 9 and the radiation of FIG. antenna 4, FIG.
• FIGS. 11 to 15 A variant embodiment of an antenna system in accordance with the present invention will now be described with reference to FIGS. 11 to 15.
• the two F-inverted antennas were made as in the embodiment of FIG. 1.
• FIG. 11 A structure as shown in FIG. 11 was simulated using the apparatus mentioned above. In this case, the following dimensions were used for the simulation, namely:
• the slot 6 has a width of 2 mm and a length of 23 mm.
• the slot made in the ground plane is a rectangular slot placed in the axis of symmetry of the structure, as shown in Figure 11, so as to maintain the symmetry of the diagrams.
• FIG. 12 giving the adaptation curves S11, S22 and the isolation curve S21 of the system of FIG. 11, there is an improvement in the insulation between the two ports, this insulation having values up to -22 dB. There is also an adaptation over the entire frequency band around 2.5 GHz.
• the presence of the slot 6 thus makes it possible to reinforce the decorrelation between the radiation of the antennas 3 and 4, as can be seen in FIGS. 13 and 14 respectively representing the radiation pattern of the antenna 3 and the radiation pattern of the antenna. antenna 4.
• FIG. 16 there is shown yet another embodiment of an antenna system according to the present invention.
• a substrate 1 comprising at least one upper conductive layer and one lower conductive layer
• two antennas of the F-inverted type have been etched by etching a strand 3A on one face and a strand 3B on the other side of the substrate. , likewise for the antenna 4.
• These strands 3A, 3B or 4A, 4B are connected by vias or metallized holes 3C as shown in FIG. 16.
• the advantage of this embodiment is the widening of the frequency band of 'a strand.
• Figure 16 shows an F-inverted type antenna etched on 2 metal layers. However, the invention also applies to antennas etched on several layers connected by metallized holes.
• an antenna solution is obtained integrating a second order of radiation diversity compatible with the most stringent cost constraints and very easily integrable on a motherboard for a wireless communication device such as a device. type WIFI.
• the integration of the antenna system described above is possible on any wireless transmission device.
• the antenna accesses are adapted to 50 ohms and are therefore directly integrable with a SPDT type switch ("Single Port Double Through” in English) or DPDT ("Double Port Double Through” in English) and the overall size of the system is as its use on already existing maps can be considered very easily.

Landscapes

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

Applications Claiming Priority (2)

Publications (1)

Family

ID=36143435

Family Applications (1)

Country Status (7)

Families Citing this family (23)

Family Cites Families (11)

• 2005
  • 2005-07-13 FR FR0552194A patent/FR2888675A1/fr not_active Withdrawn
• 2006
  • 2006-07-13 WO PCT/FR2006/001737 patent/WO2007006982A1/fr active Application Filing
  • 2006-07-13 US US11/988,776 patent/US20090073047A1/en not_active Abandoned
  • 2006-07-13 KR KR1020077030986A patent/KR20080025703A/ko not_active Application Discontinuation
  • 2006-07-13 JP JP2008520921A patent/JP2009501468A/ja active Pending
  • 2006-07-13 EP EP06794184A patent/EP1902491A1/de not_active Withdrawn
  • 2006-07-13 CN CNA2006800255803A patent/CN101223672A/zh active Pending

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events