[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

CA2136048A1 - Switched array for mobile satellite communication - Google Patents

Switched array for mobile satellite communication

Info

Publication number
CA2136048A1
CA2136048A1 CA 2136048 CA2136048A CA2136048A1 CA 2136048 A1 CA2136048 A1 CA 2136048A1 CA 2136048 CA2136048 CA 2136048 CA 2136048 A CA2136048 A CA 2136048A CA 2136048 A1 CA2136048 A1 CA 2136048A1
Authority
CA
Canada
Prior art keywords
coupled
switch
vehicle
azimuth
grating lobes
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.)
Abandoned
Application number
CA 2136048
Other languages
French (fr)
Inventor
Timothy G. Waterman
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.)
CBS Corp
Original Assignee
Individual
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 Individual filed Critical Individual
Publication of CA2136048A1 publication Critical patent/CA2136048A1/en
Abandoned legal-status Critical Current

Links

Landscapes

  • Variable-Direction Aerials And Aerial Arrays (AREA)

Abstract

ABSTRACT OF THE DISCLOSURE
A roof top antenna for moving vehicles for discriminating among geostationary satellites, the antenna comprising four linear arrays for radiating four sets of grating lobes in azimuth at six different elevations from zenith by using switching circuits to steer the grating lobes.

Description

21360~8 .

.` ~. - ..~ . .

l S7,732 SWITCHED ARRAY FOR MOBILE SATELLITE COMMUNICATIONS

BACKGROUND OF THE INVENTION
The present in~ention relates to a mobile station that can talk to communication satellites. More particularly, the present invention relates to an antenna on a mobile vehicle.
Antennas on a mobile vehicle need to fullfil certain requiremente in order to be successful. These requirements lnclude moderate gain (greater than or equal to thirteen decibels) from zenlth to ninety degrees; narrow beam width in azimuth to discriminate among satellites; three hundred and sixty degree coverage in azimuth; and low profile for practical and cosmetic reason-. In addition, the antenna should be simply and inexpensively implemented.
Although widely applicable, the invention is especially useful in a mobile vehicle communication eyetem.
Radio wave communication has been popular in various fields. With miniaturization of electronic instruments, such as, transmitter-receivers, radio wave communication is now applied to mobile communication systems, for example, mobile telephones. ~hese systems, however, are limited in geographic area because of the necessity of base stations used as repeaters to cover any given ~rea.

,, :

-2 57,732 Mobile communications systems are known which utilize a communication satellite rather than repeaters. Such systems provide advantages over mobile telephones. For example the mobile satellite communication system is not 5limited in geographic area, and thus is capable of providing coverage on a nationwide scale. Additionally, mobile satellite communication systems can transmit at a higher rate than telephone lines, and are thus capable of providing higher-guality service.
loThe antenna system on the mobile vehicle becomes a very important factor in a mobile satellite communication system because a lobe of sufficient gain and beamwidth, characteristic of the antenna, mu6t be directed towards the satellite. See U.S. Patent No. 5,166,693 issued to 15Nishikawa èt al. This becomes increasingly important for a land mobile vehicle because it is frequently steered and turned to change direction at high speeds and also because of the inclination of the vehicle as it rises and descends inclinations.
20Several method~iexist for directing a lobe towards the satellite. For example, the antenna may be physically rotated to point a lobe at the satellite. But this mechanical-steering method is unwieldy for large antennas, for example, a large antenna that i8 required to obtain 25greater gain or narrower beam width.
Alternatively, as in a phased array antenna, the beam may be electronically steered. Such an antenna apparatus for tracking a communication satellite has been known. See .; ~ .

2~36048 3 57,732 U.S. Patent No. 5,157,407 issued to Omiya and U.S. Patent ;~
No. 5,166,693 issued to Nishikawa et al. However, these have the disadvantage of a complex and expensive control apparatus for phase steering the beam to maintain communication with the satellite. `~
Moreover, not only is it important that the antenna lobe be directed to the satellite, but also the antenna ; `~
must be as small and thin as possible to provide a low air resistance when the vehicle i6 moving and be cosmetically appealing. ~;`

SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a rooftop antenna for moving vehicles that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
To achieve these and other advantages and in ;~
accordance with the purpose of the invention, as embodied and broadly described, the invention i~ for a mobile antenna system for discriminating among any one of a plurality of geo~tationary satellites positioned at least five degrees or more apart from each other in azimuth, the mobile antenna system comprising four linear arrays arranged in opposing pairs, one each at a fore, aft, left, and right area of the vehicle, for radiating any one of at four sets of grating lobes in azimuth, in any one of four predetermined quadrants relative to the vehicle, and at any one of at least six elevations from zenith down to at least , ,~
'A

` 21360~8 4 57,732 sixty-five degrees in elevation, each set of grating lobes includes at least eight lobes with nulls separated from peaks by at least about five degrees in azimuth, and each peak has a gain of at least about thirteen decibels, a plurality of first switches, for selecting the one of at least six elevations, one each coupled to a corresponding one of the four linear arrays, and a second switch, for selecting the one of at least four sets of grating lobes, located inside the vehicle and coupled to the plurality of first switches, and an alternating current power supply, for supplying power to the four linear arrays, located inside the vehicle and coupled to the second switch.
In another aspect, the invention includes linear arrays located on the roof support panels located on the sides of the vehicle.
It i8 to be understood that both the foregoing general description and the following detailed de3cription are exemplary and explanatory only and are intended to provide further explanation of the invention as claimed. i~
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate several embodiments of the invention and together with the description serve to explain the principles of the invention.

.
.~ ~ . ., ~ ., . - . ~ -, 2~36048 ~: -5 57,732 BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective view of the rooftop antenna shown on a mobile vehicle.
Fig. 2 is a plan view of one of the four sets of grating lobes in azimuth at a representative elevation in one of the four quadrants.
Fig. 3 is a perspective view of a second embodiment of ths rooftop antenna installed on a mobile vehicle.
Fig. 4 is a diagram of the gain relative to direction in azimuth of one of the four sets of grating lobes at a representative elevation showing the nulls five degrees away from peaks within one of the four predetermined quadrants.
Fig. 5 is a diagram of the gain relative to direction in azimuth of one of the twelve circularly polarized radiating elements comprising a linear array.
Fig. 6 is a diagram of the overlapping gain relative to direction in elevation of one of the four sets of grating lobes at the six different elevations showing a gain at all elevations of equal to or greater than thirteen decibel6.
Fig. 7 is a diagram of the overlapping gain relative to direction in azimuth of the four sets of grating lobes at zero degree Qlevation showing complete coverage of a .
predetermined quadrant.
Fig. 8 is a perspective view of the twelve circularly polarized elements of a linear array.

: .

;, .j '': , ~ ~ .

2136~8 6 57,732 Fig. 9 is a schematic diagram of a twelve-by-twelve orthogonal matrix.
Fig. 10 is a schematic diagram of a two coupler network and switches.
Fig. 11 is a schematic block diagram illustrating the connections of the ma;or components of the mobile antenna system of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIME~TS
Reference will now be made in detail to the present preferred embodiments of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.
The exemplary embodiment of the mobile antenna system of the present invention is shown in Fig. 1 and is designated generally by reference numeral 10.
As embodied herein and referring tv Fig. 1, the mobile antenna system comprises four linear arrays 12 mounted on a roof of a vehicle 20 to form a rectangular area 14 about forty-four inches square, an alternating current power i,. l . ': ~ ,, "
li. , ,: , , . :" ~, . ..

'~1360~8 7 57,732 supply 82 for supplying power to the four linear arrays 12, ~ ~
first switches 84 coupled to the linear arrays 12, second ~ -switch 86 coupled to the first switches 84 and power supply 82. A block diagram of the connection of the major components is shown in Fig. 11.
- .
Zenith is a point vertically above the vehicle:
elevation is measured down in an arc from zenith; and azimuth is measured along the horizon.
As shown in Fig. 2, the linear arrays 12 are ;
geometrically configured and operated in opposing pairs so that the antenna system radiates any one of four sets of grating lobes 24 in any one of four predetermined quadrants 22 when the second switch 86 is operated. Each quadrant 22 is outlined by the diagonals of the rectangular area 14. ~-~
,:
As shown in Figs. 2 and 4, each set of grating lobes 24 radiated by opposing pairs of linear arrays 12 has eight lobes 26 in a quadrant with nulls 28 separated from peaks 30 by at least five degrees in azimuth. This ~ characteristic, along with the ability to generate four sets o~ grating lobes, enables, a~ shown in Fig. 7, full coverage in a quadrant 22 for communicating with satellites at least five degrees apart in azimuth. With all four quadrants, coverage is provided three-hundred-and-sixty~
.. :,:"::
degrees in azimuth. ~
Additionally, as shown in Figs. 1 and 6, four sets of ~ -grating lobes may be radiated at any one of six elevations 18 (Fig. 1) from zenith down in elevation to sixty-five `
degrees by operation Or the first switches 84. As shown in ' '' `' ' '~

.
8 57,732 Fig. 6, a thirteen decibel gain is achieved for any lobe of the four sets of grating lobes at any elevation down to sixty-five degrees.
As shown in Fig. 8, the linear arrays comprise twelve circularly polarized radiating elements 92 spaced four inches apart from their centers.
The first switches 84 may be of any suitable well known type, e.g., a radio freguency switch, but there i8 shown by way of example, a twelve-by- twelve orthogonal matrix 94 with orthogonal beam parts 95 (see Fig. 9) and fourth switch 85 (see Fig. 10) selectively connected to the orthogonal beam parts 95. The twelve-by-twelve orthogonal matrix 94 makes available 12 orthogonal simultaneous beams pointing to different elevation angles (see Fig. 6~. A
twelve-to-one fourth switch 85 selects the appropriate beam in the direction of the satellite by selecting the corresponding orthogonal beam part 95.
As shown in Fig. 10, the second switches 86 may be of any suitable well known type, e.g., a radio fregugency switch, but there is shown by way of example, transfer switches 87, a two-coupler network 96 and a fifth switch 98. Transfer switches 87 shuttle the appropriate pair of fourth switches 85 to the azimuth grating lobe select switch 98 via the two coupler network 96.
A second embodiment of the invention will now be described where like or similar parts are identified throughout the drawings by the same reference characters.

; . : :~ : . ;, . .

.... . .. .
.,.'~ , , , .

~ 2136048 9 57,732 As shown in Fig. 3, the second embodiment is similar to the first embodiment except the linear arrays 12 are mounted on the side roof panels 30 of vehicle 20. This embodiment of the invention can provide coverage at elevations greater than sixty-five degrees from zenith with a gain greater than or equal to 13 decibels.
The major components, and their connections, are substantially the same as shown in Fig. 11, and are operated in substantially the same way, except ad~acent pairs of linear arrays are operated in tandem for radiating the grating lobes.
It will be apparent to those skilled in the art that various modifications and variations can be made in the mobile antenna system of the present invention without departing from the scope of the invention. Thus, it i8 intended that the present invention cover the modifications and variations of this invention provided they come within the sicope of the appended claimsi and their equivalents.

", :;"" "''"', .,

Claims (5)

1. A mobile antenna system affixed to a vehicle for discriminating among any one of a plurality of geostationary satellites positioned at least five degrees or more apart from each other in azimuth, the mobile antenna comprising:
a. four linear arrays operated in opposing pairs, one each positioned at a fore, aft, left, and right area of the vehicle, for radiating any one of at least four sets of grating lobes in azimuth, in any one of four predetermined quadrants relative to the vehicle, and at any one of at least six elevations from zenith down to at least sixty-five degrees in elevation, (1) each set of grating lobes includes at least eight lobes with nulls separated from peaks by at least about five degrees in azimuth, and (2) each peak has a gain of at least about thirteen decibels;
b. a plurality of first switches, for selecting the one of at least six elevations, one each coupled to a corresponding one of the four linear arrays;

c. a second switch, for selecting the one of at least four sets of grating lobes, located inside the vehicle and coupled to the plurality of first switches; and d. an alternating current power supply, for supplying power to the four linear arrays, located inside the vehicle and coupled to the second switch.
2. A mobile antenna system according to claim 1 wherein:
a. each linear array has a length of about forty-four inches, and twelve circularly polarized radiating elements equally spaced along the length; and b. each opposing pair of linear arrays being spaced about forty-four inches apart.
3. A mobile antenna system according to claim 1, wherein each second switch comprises:
a. a first transfer switch coupled to the first switch coupled to the linear array located at the fore area and to the first switch coupled to the linear array located at the left area;
b. a second transfer switch coupled to the first switch coupled to the linear array located at the aft area and to the first switch coupled to the linear array located at the right area;
c. a two-coupler network coupled to the first and second transfer switches and having four terminals corresponding to the four sets of grating lobes in azimuth;
and d. a fifth switch coupled to the power supply and selectively coupled to any one of the four terminals.
4. A mobile antenna system according to claim 1, each switch first comprising:
a. a twelve-by-twelve orthogonal matrix coupled the corresponding linear array; and b. a fourth switch coupled between the corresponding twelve-by-twelve orthogonal matrix and the second switch.
5. A mobile antenna system affixed to a vehicle for discriminating among any one of a plurality of geostationary satellites positioned at least five degrees or more apart from each other in azimuth, the mobile antenna comprising:
a. four linear arrays operated in adjacent pairs, one each positioned at the roof support pillars of the vehicle, for radiating any one of at least four sets of grating lobes in any one of four predetermined quadrants relative to the vehicle, and at any one of at least six elevations from zenith, (1) each set of grating lobes includes at least eight lobes with nulls separated from peaks by at least about five degrees in azimuth, and (2) each peak has a gain of at least about thirteen decibels;

b. a plurality of first switches, for selecting the one of at least six elevations, one each coupled to a corresponding one of the four linear arrays;
c. a second switch, for selecting the one of at least four sets of grating lobes, located inside the vehicle and coupled to the plurality of first switches; and d. an alternating current power supply, for supplying power to the four linear arrays, located inside the vehicle and coupled to the second switch.
CA 2136048 1993-11-18 1994-11-17 Switched array for mobile satellite communication Abandoned CA2136048A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US15405293A 1993-11-18 1993-11-18
US154052 1993-11-18

Publications (1)

Publication Number Publication Date
CA2136048A1 true CA2136048A1 (en) 1995-05-19

Family

ID=22549796

Family Applications (1)

Application Number Title Priority Date Filing Date
CA 2136048 Abandoned CA2136048A1 (en) 1993-11-18 1994-11-17 Switched array for mobile satellite communication

Country Status (2)

Country Link
AU (1) AU7755894A (en)
CA (1) CA2136048A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010043750A1 (en) 2008-10-13 2010-04-22 Elektrobit Wireless Communications Oy Antenna beam
EP3040736A1 (en) * 2015-01-05 2016-07-06 Delphi Technologies, Inc. Radar antenna assembly with panoramic detection

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010043750A1 (en) 2008-10-13 2010-04-22 Elektrobit Wireless Communications Oy Antenna beam
EP2347470A1 (en) * 2008-10-13 2011-07-27 Elektrobit Wireless Communications Oy Antenna beam
US20110188418A1 (en) * 2008-10-13 2011-08-04 Elektrobit Wireless Communications Oy Antenna beam
EP2347470A4 (en) * 2008-10-13 2012-04-11 Elektrobit Wireless Comm Oy Antenna beam
US9634388B2 (en) * 2008-10-13 2017-04-25 Elektrobit Wireless Communications Oy Antenna beam
EP3040736A1 (en) * 2015-01-05 2016-07-06 Delphi Technologies, Inc. Radar antenna assembly with panoramic detection
US9851436B2 (en) 2015-01-05 2017-12-26 Delphi Technologies, Inc. Radar antenna assembly with panoramic detection
EP3771920A1 (en) * 2015-01-05 2021-02-03 Aptiv Technologies Limited Radar antenna assembly with panoramic detection

Also Published As

Publication number Publication date
AU7755894A (en) 1995-05-25

Similar Documents

Publication Publication Date Title
US20230275634A1 (en) Small cell beam-forming antennas
EP0818059B1 (en) Wide antenna lobe
EP0611490B1 (en) Terrestrial antennas for satellite communication system
US6504510B2 (en) Antenna system for use in a wireless communication system
US6304762B1 (en) Point to multipoint communication system with subsectored upstream antennas
AU686388B2 (en) Microstrip antenna array
US5548294A (en) Dielectric lens focused scanning beam antenna for satellite communication system
US3340531A (en) Satellite communication system
US20060244669A1 (en) Low profile antenna for satellite communication
US6038459A (en) Base station antenna arrangement
US20050085270A1 (en) Wireless antenna traffic matrix
US11411301B2 (en) Compact multiband feed for small cell base station antennas
US6049305A (en) Compact antenna for low and medium earth orbit satellite communication systems
US20120119952A1 (en) Method and apparatus for controlling sidelobes of an active antenna array
US20040063467A1 (en) Antenna arangements for flexible coverage of a sector in a cellular network
US6175340B1 (en) Hybrid geostationary and low earth orbit satellite ground station antenna
FI91028C (en) Satellite Antenna device
CA2136048A1 (en) Switched array for mobile satellite communication
US20240047861A1 (en) Small cell beamforming antennas suitable for use with 5g beamforming radios and related base stations
WO2000011751A1 (en) Improved lens system for antenna system
US20230170957A1 (en) Small cell beamforming antennas suitable for use with 5g beamforming radios and related base stations
Stickland Planar arrays for MSAT and INMARSAT land mobile satellite communications
JPH0964800A (en) Mobile object sng device
Foo et al. Massive-Beam MIMO for LEO/VLEO VHTS
Hajach et al. Antenna Arrays—Application Possibility For Mobile Communication

Legal Events

Date Code Title Description
FZDE Dead