Antenna for reception of satellite radio signals emitted circularly, in a direction of rotation of the polarization

• US 8,537,063 B2
• Filed: 03/03/2010
• Issued: 09/17/2013
• Est. Priority Date: 03/03/2009
• Status: Active Grant

• Current Assignee: Delphi Delco Electronics Europe GmbH (Aptiv PLC)
• Original Assignee: Delphi Delco Electronics Europe GmbH (Aptiv PLC)
• Inventors: Lindenmeier, Stefan, Lindenmeier, Heinz, Hopf, Jochen, Reiter, Leopold
• Primary Examiner(s): DUONG, DIEU HIEN
• Application Number:
  US12/716,318
• Publication Number:
  US 20100253587A1
• Time in Patent Office: 1,294 Days
• Field of Search: 343/725, 343/726, 343/727, 343/728, 343/741, 343/742, 343/866, 343/867, 343/743, 343/748
• US Class Current: 343/728
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 21/29 Combinations of different interacting antenna units for giving a desired directional characteristic H01Q25/00 takes precedence
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 9/32 Vertical arrangement of element H01Q9/40 takes precedence
• CPC Class Codes: H01Q 9/36 with top loading

Abstract

An antenna for reception of satellite radio signals emitted circularly in the direction of rotation of polarization has a conductive base surface, an antenna connection point, an antenna element connection point and at least two antenna elements. The first antenna is a conductor loop disposed parallel to the base surface. The loop antenna has capacitors disposed along the conductor loop. The antenna connection point is coupled to an interruption of the loop antenna. This connection point feeds a ring current into the loop antenna. At least one additional antenna element extends between the antenna element connection point and the loop antenna. The additional antenna element has a polarization orientated perpendicular to the polarization of the loop antenna and an orthogonal phase in the far field.

Claims

1. An antenna for reception of satellite radio signals emitted circularly in the direction of rotation of polarization comprising:

a) a conductive base surface;

b) an antenna connection point;

c) an additional element connection point;

d) at least one antenna output connector;

e) at least two antenna elements comprising;

i) at least one antenna element formed as a loop antenna which comprises a conductor loop disposed substantially parallel but spaced apart from said base surface, said loop antenna comprising a plurality of interruptions spaced apart from each other and a plurality of capacitors, wherein at least one interruption is bridged by at least one capacitor disposed along said conductor loop, wherein said at least one loop antenna connection point is coupled to at least one interruption of said loop antenna wherein said connection point is configured to feed a ring current into said loop antenna;

ii) at least one additional antenna element linearly polarized in a spatial direction and coupled to said additional antenna element connection point;

f) a plurality of networks comprising a matching network and a phase shifter network configured to connect said at least two antenna elements to said at least one antenna output connector wherein said additional element connection point and said at least one loop antenna are coupled to each other by said plurality of networks, wherein in reciprocal operation of the antenna, the radiation fields of said loop antenna and of said at least one additional antenna element are superimposed with different phases in a far field of the antenna;

wherein said at least one additional antenna element has a polarization orientated substantially perpendicular to the polarization of said loop antenna and an essentially orthogonal phase in the far field.

2. The antenna according to claim 1, wherein said plurality of capacitors are selected on said loop to maintain an azimuthally constant current application on said loop antenna, wherein said capacitors are configured together with the conductors to provide resonance on the loop.

3. The antenna according to claim 1, wherein said loop antenna is configured so that during reciprocal operation of said antenna, the radiation fields of said loop antenna and of the at least one additional antenna element antenna are superimposed on the far field of the antenna, for production of a radiation with circular polarization with substantially a same amplitude in an angle range between 30 degrees and 60 degrees and a phase difference of 90 degrees.

4. The antenna according to of claim 1, wherein said loop antenna connection point is formed by an interruption of said antenna loop, wherein said loop antenna is formed with rotation symmetry about a center axis z, on a plane, wherein said at least one additional antenna element is structured as an electrically short substantially vertical monopole, that passes through said center axis (z) of said loop antenna above the conductive base surface, wherein said additional element connection point of said monopole, as well as said loop antenna connection point of said loop antenna are connected with said antenna output connector via said matching and phase shifter network.

5. The antenna according to claim 1, wherein said loop antenna is disposed at a distance of a height h, from said electrically conductive base surface and wherein said additional antenna element is disposed above said electrically conductive base surface of said loop antenna, wherein an elevation angle of a main radiation direction is set by way of a selection of distance of said height h and of the substantially horizontal expanse of said loop antenna, and by way of a ratio between a set of amplitudes between said loop antenna and said additional antenna element.

6. The antenna according to claim 1, wherein said matching and phase shifter network are configured such that said loop antenna and said additional antenna element are offset in orientation by 90 degrees.

7. The antenna according to claim 1, further comprising a summation network wherein said matching and phase shifter network and said summation network are configured such that when the antenna acts as a transmission antenna, said first and second antenna element antennas comprising said loop antenna, and said monopole antenna are superimposed on one another, accordingly to influence a vertical directional diagram.

8. The antenna according to claim 1, further comprising a two wire line, wherein said at least one loop antenna connection point of said loop antenna is connected with said antenna output connector, wherein said two wire line is conducted between a plane of said conductor loop of said loop antenna and said electrically conductive base surface wherein said two wire line comprises:

a) said matching network;

b) a balance-unbalance element;

c) a summation network disposed on said conductive base surface wherein a desired phase ratio is set by way of a selection of a length of said two wire line, and said phase shifter network.

9. The antenna according to claim 1, wherein said additional antenna element which is orientated perpendicular to a plane of said loop antenna is formed from a plurality of monopoles disposed with rotation symmetry relative to a center axis (z) of said loop antenna wherein said loop antenna and said monopoles are connected with one another at their lower end by way of lines, in a center axis (z) to form an antenna element connection point.

10. The antenna according to claim 1, further comprising a balance-unbalance network, wherein said antenna connection point comprises a plurality of antenna connection points comprising two sets of antenna connection points that are disposed at substantially equal distances from each other, wherein said antenna connection points are connected with a second plurality of networks comprising said balance-unbalance and adaption networks whose outputs are switched in parallel by way of at least one phase shifter network and are connected by said two-wire line.

11. The antenna according to claim 1, wherein said additional antenna element comprises a plurality of conductor parts, wherein said conductor parts are structured to be symmetrical with a plane of symmetry.

12. The antenna according to claim 1, wherein said conductor parts of said loop antenna are conductively coupled together with conductor parts of said monopole, to form a rotation-symmetrical roof capacitor, wherein said roof capacitor is structured with substantial rotation symmetry with reference to a plane of symmetry SE.

13. The antenna according to claim 12, wherein the feed of said loop antenna is formed by said monopole with said roof capacitor, and wherein both antennas are thus fed in common by the additional element connection point, whereby said loop antenna is rotated azimuthally relative to the roof capacitor, about said center axis Z, so that different azimuthal angle distances α

and β

result in the left direction of rotation and the right direction of rotation, between the substantially horizontal arms of said roof capacitor and the nearest interruption point, in each instance, with the capacitor introduced there on the loop antenna.

14. The antenna according to claim 1, further comprising a two-wire line for feeding said loop antenna, said two wire line forming a substantially vertical monopole and wherein said loop antenna forms a roof capacitor of said monopole and wherein said antenna connection points are disposed symmetrically relative to one another, wherein a reception voltage of said additional antenna element at said additional element connection point is passed to said two wire line as a common mode at one output,

wherein said antenna further comprises a power splitter and phase shifter network as a push pull mode of said two wire line at anther output of said matching network for amplitude appropriate and phase differential superimposition of the signals of said antenna output connector.

15. The antenna as in claim 1, wherein said loop antenna (14) is formed by four dipoles (21) disposed in a square having a center axis (z) lying substantially horizontally and connected at their ends by way of capacitors (16), the antenna further comprising:

a distribution network (10);

a plurality of feed lines (18) disposed centrally in a phase reference point (b), wherein said roof capacitor of said substantially vertical monopole (7a) is formed by a dipole system;

a sum formation element (34);

a difference formation element (35)

wherein a reception of said substantially horizontal and substantially vertical electrical field components is performed by said sum formation element (34) and said difference formation element (35), and wherein a phase-differential superimposition of said signals is given via said matching and phase shifter network (23) in said summation network (53).

16. The antenna according to claim 1, further comprising a two wire line, wherein one of the conductors of said two wire line is conductively connected with a conductive base surface at a ground connection point, the antenna further comprising:

a dipole network configured to weigh a reception of a substantially horizontally polarized and substantially vertically polarized electrical field, wherein said dipole network sets a common mode to push pull mode ratio on said two wire line;

at least one matching network; and

wherein another of said two conductors is connected with said antenna output connector via said at least one matching network; and

wherein a setting of phases required for producing a circular polarization is provided using said dipole network.

17. The antenna according to claim 1, wherein said antenna is structured as a multi-frequency range antenna wherein said antenna further comprises:

a) dipole networks positioned in place of discrete capacitors on said antenna, wherein said dipole networks comprise a circuit comprising a plurality of reactive elements that are introduced into interruption points of said loop antennas, and wherein said dipole networks comprise different reactive resistance values at different operating frequencies.

18. The antenna according to claim 1, wherein said loop antenna further comprises:

a common phase reference point (B), related to said transmission case,

a connector for substantially vertical polarization and a connector for substantially horizontal polarization;

a hybrid coupler having a 90 degree positive or negative phase difference, respectively,

a plurality of additional connectors comprising a LHCP connector and a RHCP connector, wherein said connectors allow separate availability of LHCP signals and RHCP signals, respectively having different directions of rotation of circular polarization,

wherein said additional antenna element comprising a monopole is configured as a rod antenna having an interruption point, and

a reactive element connected to said interruption point to configure its substantially vertical diagram.

19. The antenna according to claim 1, further comprising a common phase reference point B;

and a combined matching circuit, wherein said additional antenna element comprises a monopole, wherein said loop antenna acts as a roof capacitor, wherein said loop antenna and an adaption of said monopole and also said common phase reference point B are brought about by said combined matching circuit.

20. The antenna according to claim 19, further comprising:

a circular group line antenna element (7f), comprising a plurality of substantially horizontally polarized antenna element elements (59) disposed in a plane parallel to said conductive base surface (6) and at a distance from this plane, and with azimuthal rotation symmetry about the center Z, on a circle (K), wherein said base surface (6) comprises a common circular group antenna element connection point (60);

the antenna further comprising a power splitter and phase shifter network (31);

a plurality of feed lines (18) coupled to said power splitter and phase shifter network (31), and in the case of reciprocal operation of the antenna, excitation of said circular group antenna element (7f) occurs so that each antenna element element (59) is excited with a current having the same amplitude, but in terms of current phase, so that the amount of the current phase is selected to be equal to the azimuth angle (Φ

) of the azimuthal position of the antenna element element (59) that proceeds from an azimuthal reference line, so that the current phase rises or falls with an increasing azimuth angle (Φ

).

21. The antenna according to claim 20, wherein the substantially horizontally polarized antenna element elements (59) are disposed at the corner points of a square having the said center axis Z and are oriented perpendicular to the connecting lines between the corner point in question and the center axis Z, in each instance, and the substantially horizontally polarized antenna element elements (59) are connected with the connectors of a power splitter and phase shifter network (31) by way of a feed line (18) of equal length, in each instance, and the latter network comprising microstrip conductors (30) (15a, 15b, 15c) interconnected in a chain, formed on the conductive base surface (6), having a length of λ

/4, whereby their wave resistance values—

proceeding from a low wave resistance value at the circular group antenna element connection point (60)—

to which one of the feed lines (18) is directly connected—

is stepped up in such a manner that the signals fed into the antenna element elements (59) at the corners possess the same power and differ by 90 degrees in terms of phase, in each instance, continuously trailing one another.

22. The antenna according to claim 1, further comprising a 90 degree hybrid coupler, and a LHCP/RHCP changeover switch which are connected at said antenna output connector, wherein said coupler and said changeover switch are controlled by means of a changeover control situated in said radio receiver module so that a satellite reception signal of a set of two directions of rotation of polarization are alternately available for polarization diversity.

23. The antenna according to claim 16, wherein said dipole network has phases that are set for alternative availability of two directions of rotation of the circular polarization for polarization diversity, wherein the antenna further comprises a LHCP/RHCP changeover switch for changing a polarity of a reception voltage of said loop antenna for superimposition of the reception voltage from the substantially vertically polarized electrical field.

24. The antenna according to claim 1, further comprising:

a crossed antenna element;

a summation network wherein reception signals are passed to said summation network;

a controllable phase rotation element configured to pass reception signals to said summation network, wherein there are added additional reception signals in a weighted manner, to form a main direction in an azimuthal directional diagram, so that the azimuthal main direction is variably set by means of variable setting of said phase rotation element.

25. The antenna according to claim 24, wherein said crossed antenna element is formed as a flat antenna for mobile satellite communications.

26. The antenna according to claim 24, wherein said crossed antenna element is formed by a patch antenna for circular polarization.

27. The antenna according to claim 24, further comprising a ring line antenna element (7c) with circular polarization and azimuthally dependent phase, which is configured as a rotation-symmetrical polygonal or circular closed ring line disposed about the center axis Z, running in a substantially horizontal plane having the height h1 above said conductive base surface (6), and which is excited electrically so that the current distribution of a running line wave occurs on the ring line, the phase difference of which wave over one rotation amounts to precisely 2π

, and thus the extended length of the ring line corresponds to a line wavelength λ

.

28. The antenna according to claim 27, wherein said ring line antenna element (7c) is configured to be circular, with its center point in said center axis Z, the antenna further comprising and at least two ring line feed points (22), to produce a continuous line wave on the ring line antenna element (7c), spaced apart from one another along the ring line structure by λ

/4, at which points signals of equal size are fed in by way of feed lines (18) connected with the closed ring line, which signals are offset in phase by 90 degrees relative to one another.

29. The antenna according to claim 28, further comprising a power splitter and phase shifter network (31), which is connected on the one side with the ring line connection point (19), and on the other side the two signals of equal size, displaced from one another by 90 degrees in terms of phase, are available for feed into the ring line, and the ring line connection point (19) are passed to the summation network (53) by way of a controllable phase rotation element (39), and there, in weighted manner, are added to the other reception signals to form the main direction in the azimuthal directional diagram, so that the azimuthal main direction is variably set by means of variable setting of the phase rotation element (39).

30. The antenna as in claim 29, further comprising four ring line feed points (22) spaced apart from one another by λ

/4, in each instance, to produce a continuous line wave on said ring line antenna element (7c), at which points signals of equal size are fed into the closed ring line, which signals are offset in phase by 90 degrees relative to one another, in each instance.

31. The antenna as in claim 29, further comprising a directional coupling conductor (43) configured to produce a continuous line wave on the ring line antenna element (7c), wherein said continuous line wave is guided parallel to the ring line antenna element (7c) over an extended length of λ

/4, at an advantageous coupling distance with regard to the line wave resistance, and wherein said directional coupling conductor (43) is connected on the one side, by way of a feed line (18) and an matching network (25), with the ring line connection point (19), and on the other side, by way of a feed line (18), with the conductive base surface (6).

32. The antenna as in claim 31, however, aside from this first λ

/4 coupling conductor (43), a second directional coupling conductor (44) is coupled to a microstrip conductor (30) that runs on the conductive base surface (6), by means of parallel guidance at a slight distance, and the second directional coupling conductor (44) is connected with the first directional coupling conductor (43) by way of feed lines (18), and the microstrip conductor 30 is connected with the ring line connection point (19).

33. The antenna as in claim 32, wherein said the loop antenna (14) is configured as a square loop with loop antenna connection point (3), and the ring line antenna element (7c) is configured as a closed square line ring having the edge length of λ

/4 above said conductive base surface (6), at a distance h1 above said conductive base surface (6), and wherein the antenna further comprises;

a ramp-shaped directional coupling conductor (57) having an advantageous length of λ

/4, to produce a continuous line wave on said ring line antenna element (7c) and for contact-free coupling to said ring line antenna element(7c), which, proceeding from the ring line connection point (19) situated on the conductive base surface (6), by way of a substantially vertical feed line (18), leads to one of the corners, except for a coupling distance (58), in order to meet with said base surface (6) from there, essentially according to a ramp function, approximately below an adjacent corner, and is electrically conducted with it by way of the ground connector (62).

34. The antenna as in claim 33, further comprising ring line feed points (22) which are formed at the corners, and these are connected, by way of feed line (18) of equal length, to a connector of a power distribution network, in each instance, which network, on the other hand, is connected with the ring line connection point (19), and the power distribution network consists of microstrip conductors (30) (15a, 15b, 15c) having a length of λ

/4 interconnected in a chain and formed on the conductive base surface (6), whereby their wave resistance values—

proceeding from a low wave resistance value at the ring line connection point(19)—

at which one of the feed lines (18) is directly connected—

are stepped up in such a manner that the signals fed into the ring line antenna element (7c) at the corners possess the same power and differ by 90 degrees in terms of phase, in each instance, continuously trailing one another.

35. The antenna according to claim 33, further comprising another antenna element in the form of an outer ring line antenna element (7e), the circumference of which corresponds to two wavelengths λ

, so that in the case of excitation with signals offset from one another by 90 degrees in terms of phase, a continuous line wave occurs at ring line feed points (22) spaced apart from one another by λ

/4, along the outer ring line structure, and that the gain of these signals, proceeding from the connection point (21) of the outer ring line, is given in similar manner as for feed of the ring line antenna element (7c), and the signals at the loop antenna/monopole connection point (27) at the ring line connection point (19) and at the connection point (21) of the outer ring line are combined in the summation network (53), by way of controllable phase rotation elements (39), in weighted manner, so that an increased antenna gain is achieved at the antenna output connector (28) in the azimuthal main direction that is set.

36. An antenna for reception of satellite radio signals emitted circularly in the direction of rotation of polarization comprising:

a) a conductive base surface;

b) an antenna connection point;

c) an additional element connection point;

d) at least one antenna output connector;

e) at least two antenna elements comprising;

i) at least one antenna element formed as a loop antenna which comprises a conductor loop disposed substantially parallel but spaced apart from said base surface, said loop antenna comprising at least one interruption and at least one capacitor, wherein said at least one interruption is bridged by said at least one capacitor disposed along said conductor loop, wherein said at least one loop antenna connection point is coupled to at least one interruption of said loop antenna wherein said connection point is configured to feed a ring current into said loop antenna;

ii) at least one additional antenna element linearly polarized in a spatial direction and coupled to said additional element connection point;

f) a plurality of networks comprising a matching network and a phase shifter network configured to connect said at least two antenna elements to said at least one antenna output connector wherein said additional element connection point and said at least one loop antenna are coupled to each other by said plurality of networks, wherein in reciprocal operation of the antenna, the radiation fields of said loop antenna and of said at least one additional antenna element are superimposed with different phases in a far field of the antenna;

wherein said at least one additional antenna element has a polarization orientated substantially perpendicular to the polarization of said loop antenna and an essentially orthogonal phase in the far field.