CA2156259C - Antenna system - Google Patents

Antenna system Download PDF

Info

Publication number
CA2156259C
CA2156259C CA002156259A CA2156259A CA2156259C CA 2156259 C CA2156259 C CA 2156259C CA 002156259 A CA002156259 A CA 002156259A CA 2156259 A CA2156259 A CA 2156259A CA 2156259 C CA2156259 C CA 2156259C
Authority
CA
Canada
Prior art keywords
antenna system
antenna
slot
annular slot
circuit board
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.)
Expired - Fee Related
Application number
CA002156259A
Other languages
French (fr)
Other versions
CA2156259A1 (en
Inventor
Masahiro Fujimoto
Ali Louzir
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.)
Technicolor SA
Original Assignee
Thomson Multimedia SA
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 Thomson Multimedia SA filed Critical Thomson Multimedia SA
Publication of CA2156259A1 publication Critical patent/CA2156259A1/en
Application granted granted Critical
Publication of CA2156259C publication Critical patent/CA2156259C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q13/00Waveguide horns or mouths; Slot antennas; Leaky-waveguide antennas; Equivalent structures causing radiation along the transmission path of a guided wave
    • H01Q13/10Resonant slot antennas
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/10Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
    • H01Q19/12Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave
    • H01Q19/13Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave the primary radiating source being a single radiating element, e.g. a dipole, a slot, a waveguide termination
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00Details of, or arrangements associated with, antennas
    • H01Q1/12Supports; Mounting means
    • H01Q1/22Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/247Supports; Mounting means by structural association with other equipment or articles with receiving set with frequency mixer, e.g. for direct satellite reception or Doppler radar
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q13/00Waveguide horns or mouths; Slot antennas; Leaky-waveguide antennas; Equivalent structures causing radiation along the transmission path of a guided wave
    • H01Q13/10Resonant slot antennas
    • H01Q13/18Resonant slot antennas the slot being backed by, or formed in boundary wall of, a resonant cavity ; Open cavity antennas
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00Antenna arrays or systems
    • H01Q21/24Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction

Abstract

It is an object of the present invention to present a feeder for a microwave antenna system which can be integrated together with electronical means on a common circuit board. According to the present invention a slot antenna, preferably shaped as an annular slot (16) is provided on said circuit board (13). This slot can e.g. be etched on the backside (13a) which is normally the ground line (15) of the board (13). The antenna system according to the present invention can be used e.g. for reception of DBS signals.

Description

~'VO 94/19842 , Antenna System The present invention relates to an antenna system according to the generic part of claim 1.
It is generally known to receive radiofrequency signals with frequency values above of some hundreds Megahertz, corresponding to wavelength less than about 50 centimeters, with the aid of a parabolic refelector and a feeder located at the focal point of said reflector.
It is further known to use other focussing means as the parabolic reflector, e.g. a dielectric lens. Antenna systems using dielectric lenses, such as a Luneburg-type or a homogeneous-type lens, are known for example from the international publication WO 92/13373, where such a lens is used in conjunction with a helical antenna.
The known kinds of feeders, such as feeder horns and helical antennas, require waveguides or coaxial lines to lead the received signals to according electronic means, such as a low noise block (LNB). Such a waveguide-solution is bulky and complicate. As it uses two kinds of technologies, waveguide for the feed and microstrip for the LNB, it is a quite expensive product.
It is further known, e.g. from the article "MICROSTRIP ARRAY FOR RFLECTOR
FEED APPLICATIONS", P. S. Hall et al., Conference Proceedings of the 14th European Microwave Conference in Liege, September 10 - 13, 1984; pages 631 -636, to use a small array of conventional microstrip patches as antenna feed for just one polarisation and a relativlely narrow frequency band width.
It is further known, e.g. from "ANTENNA ENGINEERING HANDBOOK", second edition, R. C. Johnson et al., McGraw-Hill Book Company, 1989; chapter 8, to use slot antennas. Such antennas may have a rectangular, an annular shape or thelike.
It is an object of the present invention to present an antenna system with concentration means, such as a dielectric lens antenna or a parabolic reflector, and SUBSTITUTE SHEET (RULE 26) a light weight and compact feed which can be directly integrated with rear-positioned electronical means, such as a low noise block (LNB).
According to one aspect the invention provides antenna system comprising: a focussing means for focussing incoming radiation thereby providing focussed radiation, and a feeder capable of feeding polarized waves, the feeder including a circuit board on which a single annular slot and a low noise block are arranged, said annular slot acting as an annular slot antenna for the focussed radiation and being provided on a ground plate of the circuit board, and a hybrid coupler with a first waveform stub positioned in the slot for receiving a first polarized signal and a second waveform stub positioned in the slot for receiving a second polarized signal.
According to another aspect the invention provides antenna system comprising: a focussing means, a feeder capable of feeding polarized waves, the feeder including a circuit board on which a single annular slot antenna and electronic means of a low noise block are arranged, and perturbation elements provided for the reception of circularly polarized signals and include a first perturbation segment provided at plus 45 degrees and a second perturbation segment provided at plus 225 degrees from an axis of an output feed.
The invention has the advantage, comparing to existing microstrip arrays that there is less pattern disturbance by feeding circuits and that a better integration to the feed is possible by lower dimensions and by saving some components.

-2a-The use of an annular slot provides the advantages of a good polarisation diversity and of a wide frequency bandwidth coverage.
In a development of the invention the slot antenna is etched in the backside of the board used for the rear-positioned electronic means. This backside can be outside of the antenna area e.g. the conductor for ground.
Further characteristics, advantages and details of the invention will be explained in the following embodiments with the aid of the drawings.
Therein Fig. 1 shows a first embodiment using a parabolical reflector;
Fig. 2 shows an arrangement using a Luneburg-type lens;
Fig. 3 shows details of the feeder used in fig. 1 and 2;
Fig. 4-8 show different embodiments of feeders suitable for using in the embodiments of fig. 1 and fig. 2.
Fig. 1 shows a parabolical reflector 10 which focusses an incoming radiation 11 at a focal point l0a where a low noise block (LNB) 12 is located having a housing 14 ~WO 94/19842 PCTIEP94/00482 and a circuit board 13. The LNB 12 includes an integrated feed, which can also be called primary radiator and this feed will be explained in more detail later with the ' aid of fig. 3 to 8. The LNB 12 gives his signal, normally an intermediate frequency (IF) signal, to a broadcasting receiver, which is indicated by the block 9 and this receiver processes the said signal such that according audio, video and/or data signals are made available for a user or for further means to be controlled.
In fig 2 there is a hemi-spherical Luneburg-type lens 20 used as focussing means which focusses the incoming radiation 11 at a focal point 20a. The refraction index of the lens 20 is such that the focal point 20a is located near, but outside of the lens-surface.
The circuit board 13 is shown in more detail in fig. 3, including fig. 3a, which shows a side-view of the circuit board 13 along the axis A-A of fig. 3b, which shows a top-view of the circuit board 13. On the lower board side 13a there is a metallic plane 15 provided, which can be connected e.g. to ground. Inside this ground-plane there is an annular slot 16 provided, which could been etched and which works as an annular slot antenna for the radiation focussed at the focal point 10a. On the upper side 13b of the board 13 there is a first microstrip line 17 provided with a stub 17a, which receives signals of a first polarization, e.g. horizontal. For the reception of a second polarisation, orthogonal to the first one, there is a second microstrip line 18 provided having an according stub 18a. The microstrip lines 17, 18 lead their signals to according inputs of rear-positioned electronical means of the LNB 12. These electronical means are positioned on the upper side of the board 13, but are not shown due to reasons of clearness.
The dimensions and the shapes of the stubs 17a, 18a are optimized to achieve a wide frequency band width and a good isolation between the orthogonal polarizations.
In the embodiments of fig. 1 and 2 the board 13 is such provided that its broadside is directed to or around the center of the reflector 10 or of the lens 20, respectively and that the lower board-side 13a is nearer to the reflector 10 or the lens 20, respectively, than the upper board-side 13b.
SUBSTITUTE SHEET (RULE 26) It may be mentioned that it is also possible to position the upper side 13b nearer to the reflector 10 or to the lens than the lower side 13a though this may effect pattern disturbances and a more difficult construction of the housing 14.
The radiation generated by the annular slot 16 and initiated by the focussed wave 11 is bidirectional with two maximas at the broadside of the board 13. To obtain an unidirectional beam, a closed backed metallic cavity is installed in the embodiment shown in fig. 4. A metal part 30 has a first foot-bridge 31, which is in electrical contact with the ring 19, and a second foot-bridge 32 with an isolation 33 at its lower end so that an electrical contact between the part 30 and the strip line 17 is avoided. The foot-bridges 31,32 build together with the according horizontal connection of the part 30 a cavity with a height H to the upper board-side 13b of about L/4, where L is the wavelength of the radiation to be received. It may be mentioned that the dimensions in fig. 4 are such to explain this embodiment quite clearly. In reality the thickness of the board 13 and of the lines 17, 18, 19 etc. are much smaller than the height H. This means that the height of about LI4 is also nearly the distance between the annular slot and a point A.
The polarization of the wave radiated by the annular slot 16 is originally linear. The embodiment indicated in fig. 5 is suitable for the reception of circular polarisations.
Therefore there can be used an hybrid couple 40. At a first output is a first circular polarization available, e.g.right hand circular polarization (RHCP), and at a second output 42 is the other circular polarization available, e.g.left hand circular polarization (LHCP).
Another embodiment for the reception of circular polarized signals is shown in fig.
6. A first small perturbation segment 50 is provided at + 45 degrees and a second small perturbation segment 51 is provided at +225 degrees from the axis of the feeding point (microstrip line) 17. These segments 50, 51 are at the lower boardside 13a and correspond to a distortion of the annular slot 16.By these segments 50, 51 a RHCP is realized at the line 17. Compared to the axis of the feeding point (microstrip line) 18 the perturbation segments 51, 50 are arranged in SUBSTITUTE SHEET (RULE 26) A
~O 94/19842 ~ PCT/EP94/00482 about -45 degrees and -225 degrees respectively. Thereby the reception of LHCP
is realized at line 18.
Fig. 7, including fig. 7b showing a top-view of the circuit board 13, and fig.
7a, showing a cut along A-A of fig.7b, presents an embodiment where it is possible to reach a specified illumination of the focussing means 10 or 20 respectively. A
few annular slots , e.g. four one 16a, 16b, 16c, 16d like shown in fig. 7, can be grouped in a small array, arranged in a certain way and fed with an adequate power distribution circuit, thus to achieve wider frequency band width and higher polarization performance. In this case a common back cavity 30'can be used instead of individual cavities. Thus permits closer inter-element spacing and then could be used with a wider range of focussing antenna parameters, such as the ratio of the focal length F to the diameter D of the focussing means 10, 20 respectively:
F/D.
The smaller FID, the closer is the feed to the focussing means, the wider is the needed feed beamwidth which gives the illumination.
Also other parameters can be achieved.
Another solution to achieve a specified illumination is to cover the single radiation element by a small dielectric lens having spherical, cylindrical, planar or any other shape with maintaining a small feed cross section. Such a method has already been proposed by C. M. Hall et al. in the article "MICROSTRIP PATCH ARRAYS
WITH SPHERICAL DIELECTRIC OVERLAYS'; published on pages 89 - 93 of the book "Advanced Antenna Technology", Vol. 2; MICROWAVE EXHIBITIONS &
PUBLISHERS, 1987 (ISBN 094682195X) Therefore further explanations for this principle seems not to be necessary.
Versions of the described embodiments may include at least one of the following variations:
SUBSTITUTE SHEET (RULE 26) '~~.~~i~~-- Instead of an annular shape, the slot 16, 16a,... may have any other suitable shape, e.g. like shown in fig. 8.
- For the housing any material suitable for passing of the received wave 11 can be taken. Additionally or instead it is possible to provide an apperture in the area of the slots 16.
- The circuit board can be arranged at the end of a closed waveguide, with a distance between the end of this waveguide and of the circuit board of about U4.
For the calculation of the dimensions of the annular slot the method given by annex A can be used.
r SUBS'FI11lTE SHEET (RULE 26)

Claims (5)

CLAIMS:
1. Antenna system comprising:
a focussing means for focussing incoming radiation thereby providing focussed radiation, and a feeder capable of feeding polarized waves, the feeder including a circuit board on which a single annular slot and a low noise block are arranged, said annular slot acting as an annular slot antenna for the focussed radiation and being provided on a ground plate of the circuit board, and a hybrid coupler with a first waveform stub positioned in the slot for receiving a first polarized signal and a second waveform stub positioned in the slot for receiving a second polarized signal.
2. Antenna system according to claim 1, wherein a cavity is installed on the side opposite of the slot antenna and is provided to concentrate the radiation into one direction.
3. The antenna system as recited in claim 1, wherein a phase of said first and second polarized signals is dependent upon a position of said first and second stubs about said annular slot.
4. The antenna system as recited in claim 1, wherein said first and second polarized signals are in quadrature phase.
5. Antenna system comprising:
a focussing means, a feeder capable of feeding polarized waves, the feeder including a circuit board on which a single annular slot antenna and electronic means of a low noise block are arranged, and perturbation elements provided for the reception of circularly polarized signals and include a first perturbation segment provided at plus 45 degrees and a second perturbation segment provided at plus 225 degrees from an axis of an output feed.
CA002156259A 1993-02-28 1994-02-19 Antenna system Expired - Fee Related CA2156259C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP93400507.5 1993-02-28
EP93400507 1993-02-28
PCT/EP1994/000482 WO1994019842A1 (en) 1993-02-28 1994-02-19 Antenna system

Publications (2)

Publication Number Publication Date
CA2156259A1 CA2156259A1 (en) 1994-09-01
CA2156259C true CA2156259C (en) 2004-10-26

Family

ID=8214686

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002156259A Expired - Fee Related CA2156259C (en) 1993-02-28 1994-02-19 Antenna system

Country Status (9)

Country Link
EP (1) EP0686313B1 (en)
JP (1) JP3461827B2 (en)
KR (1) KR100303384B1 (en)
CN (1) CN1037882C (en)
CA (1) CA2156259C (en)
DE (1) DE69408303T2 (en)
ES (1) ES2113089T3 (en)
WO (1) WO1994019842A1 (en)
ZA (1) ZA941376B (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2304465B (en) * 1993-03-17 1997-10-22 Seiko Epson Corp Slot antenna device
FR2725561B1 (en) 1994-10-10 1996-11-08 Thomson Consumer Electronics INTEGRATED MULTIPLE SOURCE ANTENNA SYSTEM WITH LOW NOISE FREQUENCY CONVERTER
DE19633147A1 (en) * 1996-08-18 1998-02-19 Pates Tech Patentverwertung Multifocus reflector antenna
GB9811850D0 (en) 1998-06-02 1998-07-29 Cambridge Ind Ltd Antenna feeds
FR2829301A1 (en) * 2001-08-29 2003-03-07 Thomson Licensing Sa PLANAR, COMPACT, TWO-ACCESS ANTENNA AND TERMINAL COMPRISING SAME
FR2858468A1 (en) 2003-07-30 2005-02-04 Thomson Licensing Sa PLANAR ANTENNA WITH DIVERSITY OF RADIATION
FR2861222A1 (en) * 2003-10-17 2005-04-22 Thomson Licensing Sa Dual-band planar antenna for use in wireless mobile network, has outer and inner annular slots supplied by two common supply line that cuts across slots in directions of respective protrusions
CN109524795A (en) * 2018-11-22 2019-03-26 南京华讯方舟通信设备有限公司 A kind of helical antenna of loaded medium lens

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3665480A (en) * 1969-01-23 1972-05-23 Raytheon Co Annular slot antenna with stripline feed
US4208660A (en) * 1977-11-11 1980-06-17 Raytheon Company Radio frequency ring-shaped slot antenna
DE3134122A1 (en) * 1981-08-28 1983-03-17 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Antenna system with a dielectric
US4929959A (en) * 1988-03-08 1990-05-29 Communications Satellite Corporation Dual-polarized printed circuit antenna having its elements capacitively coupled to feedlines
JPH03120113U (en) * 1990-03-22 1991-12-10
JPH0548320A (en) * 1991-08-20 1993-02-26 Sumitomo Electric Ind Ltd Receiver

Also Published As

Publication number Publication date
CN1037882C (en) 1998-03-25
JP3461827B2 (en) 2003-10-27
DE69408303D1 (en) 1998-03-05
KR960701493A (en) 1996-02-24
WO1994019842A1 (en) 1994-09-01
ZA941376B (en) 1994-09-27
DE69408303T2 (en) 1998-06-10
CA2156259A1 (en) 1994-09-01
JPH08509848A (en) 1996-10-15
CN1118636A (en) 1996-03-13
KR100303384B1 (en) 2001-11-22
ES2113089T3 (en) 1998-04-16
EP0686313B1 (en) 1998-01-28
EP0686313A1 (en) 1995-12-13

Similar Documents

Publication Publication Date Title
US5892487A (en) Antenna system
US20190229427A1 (en) Integrated waveguide cavity antenna and reflector dish
US4814777A (en) Dual-polarization, omni-directional antenna system
US6720932B1 (en) Multi-frequency antenna feed
US6107897A (en) Orthogonal mode junction (OMJ) for use in antenna system
CA2203077C (en) Polarimetric dual band radiating element for synthetic aperture radar
CA2029762C (en) Dual mode antenna apparatus having slotted waveguide and broadband arrays
EP1301967B1 (en) Nested turnstile antenna
US7656358B2 (en) Antenna operable at two frequency bands simultaneously
US7847749B2 (en) Integrated waveguide cavity antenna and reflector RF feed
US7656359B2 (en) Apparatus and method for antenna RF feed
US4772890A (en) Multi-band planar antenna array
EP0965151B1 (en) Apparatus for receiving and transmitting radio signals
JP3029231B2 (en) Double circularly polarized TEM mode slot array antenna
WO2002084800A2 (en) Crossed slot cavity antenna
US6181293B1 (en) Reflector based dielectric lens antenna system including bifocal lens
CA2156259C (en) Antenna system
EP0564266B1 (en) Circular polarization apparatus for micro wave antenna
US4342034A (en) Radio frequency antenna with polarization changer and filter
EP1258948A2 (en) Semicircular radial antenna
JP2000040914A (en) Antenna device
EP0929122A2 (en) Reflector based dielectric lens antenna system
Petosa et al. Dual-polarized lens antenna for LMCS applications
JPS6236906A (en) Antenna system in common use for two polarized waves
JPH09199932A (en) Microwave receiver

Legal Events

Date Code Title Description
EEER Examination request
MKLA Lapsed

Effective date: 20140219