U.S. patent application number 14/812929 was filed with the patent office on 2018-07-12 for device and method for reducing interference with adjacent satellites using a mechanically gimbaled asymmetrical-aperture antenna.
The applicant listed for this patent is ViaSat, Inc.. Invention is credited to David H. Irvine.
Application Number | 20180198201 14/812929 |
Document ID | / |
Family ID | 49674226 |
Filed Date | 2018-07-12 |
United States Patent
Application |
20180198201 |
Kind Code |
A9 |
Irvine; David H. |
July 12, 2018 |
DEVICE AND METHOD FOR REDUCING INTERFERENCE WITH ADJACENT
SATELLITES USING A MECHANICALLY GIMBALED ASYMMETRICAL-APERTURE
ANTENNA
Abstract
Methods, apparatuses, and systems for two-way satellite
communication and an asymmetric-aperture antenna for two-way
satellite communication are disclosed. In one embodiment, a beam
pattern for an asymmetric-aperture antenna is offset in a narrow
beamwidth direction, and the offset beam pattern is directed by a
mechanical gimbal, with the beam pattern offset made to reduce
interference with an adjacent satellite. In additional embodiments,
operational areas near the equator are identified for a given
offset beam pattern, or a beam pattern offset may be adjusted over
time to compensate for movement of the asymmetric-aperture antenna
when attached to an airplane, boat, or other mobile vehicle.
Inventors: |
Irvine; David H.; (Carlsbad,
CA) |
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Applicant: |
Name |
City |
State |
Country |
Type |
ViaSat, Inc. |
Carlsbad |
CA |
US |
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Prior
Publication: |
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Document Identifier |
Publication Date |
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US 20150333398 A1 |
November 19, 2015 |
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Family ID: |
49674226 |
Appl. No.: |
14/812929 |
Filed: |
July 29, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13830323 |
Mar 14, 2013 |
9123988 |
|
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14812929 |
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61731405 |
Nov 29, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01Q 25/00 20130101;
H01Q 1/27 20130101; H01Q 1/125 20130101; H01Q 3/26 20130101; H01Q
3/28 20130101; H01Q 3/245 20130101; H01Q 3/08 20130101; H01Q 3/30
20130101 |
International
Class: |
H01Q 3/08 20060101
H01Q003/08; H01Q 1/27 20060101 H01Q001/27 |
Claims
1. (canceled)
2. An antenna for mounting on a mobile vehicle for communicating
with a satellite, the antenna comprising: a radiating surface to
produce a beam having an asymmetric antenna pattern, wherein the
asymmetric antenna pattern has a narrow-beamwidth direction and a
wide-beamwidth direction; a beam steering apparatus responsive to
commands to point the beam in a direction toward the satellite, the
beam steering apparatus comprising: an azimuth adjustment to adjust
an azimuth angle of the beam; an elevation adjustment to adjust an
elevation angle of the beam; and a skew adjustment to adjust a skew
angle of the beam; and control circuitry to provide the commands to
the beam steering apparatus, wherein the provided commands are
based on a location of the mobile vehicle.
3. The antenna of claim 2, wherein the satellite is a geostationary
satellite on a geostationary arc, and the skew angle is an angle
relative to the geostationary arc.
4. The antenna of claim 2, wherein the skew adjustment adjusts the
skew angle of the beam to change a service area of the antenna for
communicating with the satellite.
5. The antenna of claim 2, wherein the skew adjustment adjusts the
skew angle of the beam to reduce interference with a second
satellite.
6. The antenna of claim 2, wherein the control circuitry changes
the commands in response to movement of at least one of the antenna
or the satellite.
7. The antenna of claim 2, wherein the commands provided to the
beam steering apparatus includes commands to control the skew
adjustment to adjust the skew angle of the beam, and further
includes commands to control the azimuth adjustment and the
elevation adjustment to maintain pointing of the beam in the
direction towards the satellite.
8. The antenna of claim 2, wherein the skew adjustment controls a
physical component of the antenna to adjust the skew angle.
9. The antenna of claim 2, wherein the skew adjustment is a
mechanical structure.
10. The antenna of claim 2, wherein the radiating surface comprises
a planar array of radiating elements.
11. The antenna of claim 2, wherein the skew adjustment adjusts the
skew angle over a range of skew angles.
12. A method comprising: associating an antenna mounted on a mobile
vehicle with a satellite for communications, wherein the antenna
comprises a radiating surface to produce a beam having an
asymmetric antenna pattern with a narrow-beamwidth direction and a
wide-beamwidth direction, and a beam steering apparatus to adjust
an azimuth angle of the beam, adjust an elevation angle of the
beam, and adjust a skew angle of the beam; and pointing, using the
beam steering apparatus, the beam in a direction toward the
satellite from a first location of the antenna, the pointing
comprising adjusting the azimuth angle, the elevation angle and the
skew angle of the beam based on the first location.
13. The method of claim 12, further comprising pointing, using the
beam steering apparatus, the beam toward the satellite from a
second location of the antenna, the pointing from the second
location comprising further adjusting the azimuth angle, the
elevation angle and the skew angle based on the second
location.
14. The method of claim 12, wherein the mobile vehicle is an
aircraft.
15. The method of claim 12, wherein the satellite is a
geostationary satellite on a geostationary arc, and the skew angle
is an angle relative to the geostationary arc.
16. The method of claim 12, wherein adjustment of the skew angle of
the beam changes a service area of the antenna for communicating
with the satellite.
17. The method of claim 12, wherein adjustment of the skew angle of
the beam reduces interference with a second satellite.
18. The method of claim 12, further comprising adjusting the skew
angle of the beam and maintaining pointing the beam in the
direction of the satellite using the beam steering apparatus.
19. The method of claim 12, wherein the beam steering apparatus
controls a physical component of the antenna to adjust the skew
angle.
20. The method of claim 12, wherein the beam steering apparatus
includes a mechanical structure to adjust the skew angle.
21. The method of claim 12, wherein the radiating surface comprises
a planar array of radiating elements.
Description
CROSS REFERENCE
[0001] The present application is a continuation of U.S. patent
application Ser. No. 13/830,232, filed on Mar. 14, 2013, entitled,
"DEVICE AND METHOD FOR REDUCING INTERFERENCE WITH ADJACENT
SATELLITES USING A MECHANICALLY GIMBALED ASYMMETRICAL-APERTURE
ANTENNA," which claims the benefit of U.S. Provisional Patent
Application Ser. No. 61/731,405, filed Nov. 29, 2012, entitled
"DEVICE AND METHOD FOR REDUCING INTERFERENCE WITH ADJACENT
SATELLITES USING A MECHANICALLY GIMBALED ASYMMETRICAL-APERTURE
ANTENNA," each of which are incorporated herein by reference in
their entirety.
BACKGROUND
[0002] This disclosure relates in general to communications and,
but not by way of limitation, to satellite communication systems as
well as antenna design and antenna operation to reduce interference
with adjacent satellites during two way communications from mobile
antennas to a target satellite.
[0003] Satellites are either in geostationary orbit (GSO) which is
an orbit where the satellite is stationary relative to the surface
of the earth, or in non-geostationary orbit (NGSO), traveling
around the earth. A GSO satellite is in orbit approximately 35,800
km above the equator, and has a revolution around the earth that is
synchronized with the earth's rotation. Therefore, the GSO
satellite appears fixed in the sky to an observer on the earth's
surface. GSO satellites may be placed anywhere along an arc above
the earth's equator, which results in a significant number of
adjacent satellites in a GSO, forming an arc of satellites across
the sky in GSO that is referred to herein as the geostationary arc.
One potential source of signal degradation in two-way
communications between antennas and a target satellite is
interference to and from a satellite that is adjacent to the target
satellite.
[0004] There are a number of antenna solutions suitable for two-way
mobile use, e.g. on aircraft, trains, boats, or trucks. These can
be classified into various categories. One category is two-axis
mechanically steerable asymmetric-aperture antennas. These work
well at middle and high latitude due to the low scan loss for the
antenna elevation angles at these latitudes. At low latitudes,
however, there are scan loss and skew issues that create
interference with adjacent satellites on the geostationary arc. A
second category is planar arrays. These work well at middle to low
latitudes. At high latitudes, however, these antennas suffer scan
loss. Therefore, neither of the two types of antennas mentioned
here work well at both extremes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The present disclosure is described in conjunction with the
appended figures:
[0006] FIG. 1A shows a one aspect of an embodiment of a satellite
communications system for use with various embodiments of the
innovations presented herein;
[0007] FIG. 1B shows a one aspect of an embodiment of a satellite
communications system for use with various embodiments of the
innovations presented herein;
[0008] FIG. 1C shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0009] FIG. 1D shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0010] FIG. 1E shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0011] FIG. 1F shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0012] FIG. 1G shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0013] FIG. 1H shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0014] FIG. 2A illustrates an allowable antenna operation footprint
of an embodiment of a satellite communications system for use with
various embodiments of the innovations presented herein;
[0015] FIG. 2B illustrates an allowable antenna operation footprint
of an embodiment of a satellite communications system for use with
various embodiments of the innovations presented herein;
[0016] FIG. 2C illustrates an allowable antenna operation footprint
of an embodiment of a satellite communications system for use with
various embodiments of the innovations presented herein;
[0017] FIG. 3A illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0018] FIG. 3B illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0019] FIG. 3C illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0020] FIG. 3D illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0021] FIG. 3E illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0022] FIG. 4A illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0023] FIG. 4B illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0024] FIG. 4C illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0025] FIG. 4D illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0026] FIG. 4E illustrates a beam pattern from an
asymmetric-aperture antenna in accordance with one potential
embodiment;
[0027] FIG. 5 shows a one potential method of operating a satellite
communications system in accordance with an embodiment;
[0028] FIG. 6 shows one potential implementation of a computing
device that may be used in accordance with various embodiments;
[0029] FIG. 7 shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0030] FIG. 8 shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0031] FIG. 9 shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0032] FIG. 10 shows a one aspect of an embodiment of an
asymmetric-aperture antenna in accordance with various embodiments
of the innovations presented herein;
[0033] In the appended figures, similar components and/or features
may have the same reference label. Further, various components of
the same type may be distinguished by following the reference label
by a dash and a second label or a letter label in conjunction with
a number label that distinguishes among the similar components. If
only the first reference label is used in the specification, the
description is applicable to any one of the similar components
having the same first reference label irrespective of the second
reference label or letter associated with the first reverence
label.
DETAILED DESCRIPTION
[0034] Embodiments disclosed herein relate to two-way satellite
communications using asymmetric-aperture antennas configured to
reduce or modify interference with satellites adjacent to a target
communications satellite at certain locations. These communications
systems and antennas are especially relevant for mobile airborne or
ground communications, where an antenna is mounted on an airplane,
truck, boat, or other vehicle. These communication systems may
further improve the locations near the equator where certain
asymmetric-aperture antennas may function.
[0035] One potential embodiment may operate in an airplane that
travels between a first location where the skew between an antenna
beam pattern and the geo arc allows an acceptable communication
with the target satellite, and a second location where the skew of
an antenna beam pattern will cause excessive interference with
adjacent satellites. In such an installation, the beam pattern may
be offset from the perpendicular direction away from a planar
radiating surface of the antenna. A mechanical gimbal that directs
the beam pattern may then adjust to direct the offset beam pattern
toward the target satellite. Such an adjustment will alter the skew
of the beam pattern, and if the adjustment is done appropriately
relative to the geostationary arc, the interference with adjacent
satellites may be reduced or limited to an acceptable level.
Various embodiments for implementing such a system and antenna
structure will be detailed below.
[0036] FIG. 1A illustrates a two-way communication system between a
target satellite shown as satellite 110, and a plurality of users
operating with asymmetric aperture antennas, shown as a boat having
asymmetric aperture antenna 130, an airplane having asymmetric
aperture antenna 140, and a truck having asymmetric aperture
antenna 150. Each asymmetric aperture antenna communicates with
satellite 110 with an electromagnetic transmission that may be
considered to be in the form of a beam pattern. Antenna 130 has
beam pattern 132, antenna 150 has beam pattern 152, and antenna 140
has beam pattern 142. Such a system may account for interference
with adjacent satellites 112a and 112b. As will be discussed in
more detail in the next few figures, the beam pattern is not a
tightly focused beam, but instead may be considered to have a
center directional vector, and for an asymmetric-aperture antenna,
both long and narrow beam pattern axis. When the long beam pattern
axis of an antenna aligns with the geo arc, if the pattern is
sufficiently broad, interference problems may arise from this low
skew alignment.
[0037] FIGS. 1B through 1E provide additional details to describe
the beam pattern of an asymmetrical-aperture antenna, and to
explain the relationship between the beam pattern, the antenna
radiating surface, and the control and direction of the
antenna.
[0038] FIG. 1B shows another perspective of an asymmetric aperture
antenna 120. The horizon from the perspective of the antenna is
illustrated by oval 101. The control and position of antenna 120,
and the direction of the beam pattern from the antenna may be
identified with respect to a reference 102. In certain embodiments,
reference 102 may be considered a north direction along the ground
at the horizon, as seen by antenna 120. The angle of adjustment
along the horizon is considered azimuth 124, and the angle of
adjustment up from the horizon is considered elevation 126. The
direction of the center of beam pattern 122 for direction toward
satellite 110 may thus be identified by a value for an azimuth 124
and elevation 126 adjustment.
[0039] FIGS. 1C and 1D show more detail of a radiating surface 127,
which may also be seen in an illustrative embodiment of an
asymmetric aperture antenna 120 shown in FIGS. 1F, 1G, and 1H. The
radiating surface as shown in FIG. 1 is a planar surface, but in
various alternative embodiments, may be non-planar. In the
illustrative embodiment of FIG. 1C, radiating surface 127 has a
long physical radiating surface direction along the y axis and a
narrow physical radiating surface direction along the x axis. In an
operation with no offset of the beam pattern, the center of the
beam pattern will be at the z axis, which is perpendicular to the
plane of the radiating surface, or 90 degrees from both the x and y
axis when the radiating surface is in the x-y plane.
[0040] In various embodiments, the beam pattern is "offset" to form
an offset beam pattern. An offset beam pattern is a beam pattern
having a center in offset beam direction 131 as shown in FIG. 1C
and FIG. 1D. As further shown in FIG. 1C, the offset angle 129 for
offset beam direction 131 is in the z-y plane, when the long
physical radiating surface is along the y-axis.
[0041] FIG. 1E shows an illustrative description of a beam pattern
122, having a long axis 123 and a narrow axis. The perspective of
the beam pattern 122 is shown as if the observer is looking down
beam pattern 122 toward the radiating surface 127 of antenna 120.
Due to the nature of operation of an asymmetric-aperture antenna,
and as illustratively shown by FIG. 1B, the beam pattern long axis
123 extends in the same direction as the narrow physical radiating
surface. Similarly, the beam pattern narrow axis 125 extends in the
same direction as the long physical radiating surface direction.
Therefore, if the beam pattern 122 is offset in offset beam
direction 131, this offset is in the beam pattern narrow axis 125
direction and in the long physical radiating surface direction.
This offset as shown in FIG. 1C will be referred to as an offset in
the narrow beamwidth direction.
[0042] As a further illustration of this offset, FIG. 1E describes
a cross section of the beam pattern from asymmetric antenna 120.
This cross section is located away from the antenna at a
significant distance along the vector defining the center of the
beam pattern, similar to the elliptical cross section of the beam
pattern 122 away from antenna 120 as illustrated in FIG. 1B. For an
antenna with a planar radiating surface, this cross section is in a
plane parallel to the radiating surface. FIG. 1E further shows
normal/perpendicular line (128) intersection for a non-offset beam
pattern 192, as well as normal/perpendicular line (128)
intersection of offset beam pattern 194. In other words, for a
non-offset beam pattern having the shape shown in FIG. 1E, the
perpendicular line from radiating surface 128 along the z-axis in
FIG. 1C will intercept the pattern shown in FIG. 1E at intersection
for--non-offset beam pattern 192. For a beam pattern 122 that is
offset by offset angle 129 in offset beam direction 131, the
perpendicular line from radiating surface 128 along the z-axis will
be far off from the center along beam pattern narrow axis 125, with
an intersection as shown at intersection for offset beam pattern
194. As offset angle 129 grows, the intersection point for 194
would move further and further from the center of the beam pattern
122 of FIG. 1E.
[0043] FIGS. 1F, 1G, and 1H show one potential embodiment of a low
profile asymmetric aperture antenna detailed as asymmetric-aperture
antenna 120. Asymmetric-aperture antenna 120 includes radiating
surface 127, mechanical gimbal elevation adjustment 1026 and
mechanical gimbal azimuth adjustment 1024. FIG. 1F shows antenna
120 with the mechanical gimbal elevation adjustment 1026 at a large
elevation 126 angle, while FIG. 1G shows mechanical gimbal
elevation adjustment 126 at a low elevation 126 angle, pointed near
horizon 101. In both FIG. 1F and FIG. 1G, mechanical gimbal azimuth
adjustment 1024 is not visible, and would be at the bottom of
antenna 120 as shown in FIG. 1H. Further, the low profile shown
serves to reduce the wind drag when the antenna is mounted to a
mobile vehicle. Especially at high speeds, such as in an antenna
mounted to an aircraft, the use of a low profile
asymmetric-aperture antenna in conjunction with systems for
reducing adjacent satellite interference may provide improved
performance and deployment characteristics such as improved
performance from locations near the equator.
[0044] FIG. 1H shows a bottom view of antenna 120 with an enlarged
section illustrating mechanical gimbal azimuth adjustment 1024. As
mechanical gimbal azimuth adjustment 1024 rotates antenna 120 about
a center point of antenna 120, the perpendicular line from the
radiating surface 128 sweeps to a new azimuth 124 direction.
Mechanical gimbal azimuth adjustment 1024 as shown adjusts a center
point of antenna 120. In alternate embodiments, azimuth 124 may be
adjusted from any point, including points on a mounting surface at
an edge or away from the antenna. Similarly, while mechanical
gimbal elevation adjustment 1026 is shown as rotating radiating
surface 127 around the y-axis through the center of the physical
long portion of the radiating surface, this rotation may be at an
edge or outside radiating surface 127, as long as the perpendicular
line from radiating surface 128 is adjusted to an elevation
126.
[0045] FIGS. 2A, 2B, and 2C illustrate acceptable antenna placement
areas for an antenna having a given set of antenna beam
characteristics with no offset and with a first offset in the
narrow beamwidth direction that is communicating with a target
satellite above geostationary point 204.
[0046] FIG. 2A shows a map of the globe with geostationary point
204 along equator 202, illustrating areas 210a and 210b nearer to
the equator 202 that may be acceptable areas for antenna operation
for an antenna with an offset beam pattern. The service areas 212
and 214 may be determined by a combination of antenna
characteristics, an antenna beam offset, satellite location, and
regulatory standards that set interference levels and communication
characteristics for two way communications with satellites.
[0047] FIG. 2B shows a service area 212 for an antenna with no beam
pattern offset, and FIG. 2C shows a service area 214 for an antenna
having a beam pattern offset. As shown in FIG. 2B, service area 212
provides a very minimal amount of coverage near equator 202. While
an antenna with a beam pattern offset as shown by FIG. 2C does not
include additional overall service area, service may be provided
for a significantly greater area near the equator while maintaining
significant service area away from the equator. As shown by FIG.
2A, such a system may enable an improvement for airplanes or boats
traveling from North America to Central America in providing
continuous two-way communication from a single asymmetric-aperture
antenna to a single target satellite.
[0048] FIGS. 3 and 4 illustrate the relationship between a beam
pattern and the geosynchronous arc for antennas at the same global
surface location near the equator.
[0049] FIG. 3 illustrates the relationship between a beam pattern
wide axis 323 and the geosynchronous arc for an antenna 320 with no
beam pattern offset, from a multiple perspectives. FIG. 3A shows a
side angle looking at antenna 320. FIG. 3B shows a top angle
looking down through a target satellite toward antenna 320. FIGS.
3C, 3D, and 3E all show additional views of the same antenna
320.
[0050] FIG. 4 illustrates the relationship between a beam pattern
wide axis 423 and the geosynchronous arc for an antenna 420 with a
beam offset in the narrow beamwidth direction. The antenna
illustrated in FIG. 4 is estimated for the same characteristics,
same global surface location, and same geostationary satellite
point as the satellite of FIG. 3. The difference is that the beam
pattern wide axis 423 for antenna 420 has been offset in the narrow
beamwidth direction, and the azimuth and elevation adjusted to
direct the offset beam pattern toward the satellite. As seen in
FIG. 3, when antenna 320 is located near the equator, the skew
angle between the geo arc 302 and the beam pattern wide axis 323 is
low, and so the signal from antenna 320 will have a greater
interference with adjacent satellites. As seen in FIG. 4, this
adjustment alters the skew angle between beam pattern wide axis 423
and geosynchronous arc 402 to create a greater angle. This reduces
the amount of interference with adjacent satellites, and adjusts
the locations for which operation is possible. When viewed with
respect to FIG. 2, the areas in which the offset beam pattern more
closely aligns with the geosynchronous arc can be seen, as well as
area 210 where the beam pattern offset significantly improves the
skew alignment between the beam pattern and the geosynchronous
arc.
[0051] In various alternative embodiments, the offset angle may be
implemented in an asymmetric-aperture antenna in different ways. In
one potential embodiment, a fixed offset angle is built into the
design of the antenna. In such an embodiment, an offset may be
mechanically or electrically set in the antenna design in a
non-adjustable format, such that a narrow beamwidth offset angle
such as offset angle 129 of FIG. 1 cannot be adjusted during
operation. This could enable use of the antenna over a different
footprint with respect to the satellite than an antenna with no
offset would, potentially at a lower cost than adjustable designs,
with the disadvantage that the antenna would be
footprint-specific.
[0052] Another potential embodiment may use a stepwise-steerable
one dimensional phased array. This allows more flexibility in the
use of the antenna across all regions. The disadvantage is a more
complex antenna design. Dependent on the specific embodiment, this
may or may not involve a larger swept volume or longer beamwidth
axis. Multiple alternative methods of steering the antenna beam in
such an embodiment are possible. One potential embodiment to
accomplish the desired steerability would be to use a Rotman lens
and associated switches. A Rotman lens has the advantage of being a
printed structure, without any active elements other than an array
of switches to select which port is active. In such an embodiment
the lens may be attached to a modified antenna such as antenna 120
of FIG. 1 without increasing its swept volume.
[0053] An additional potential alternative embodiment may use an
electronically steerable phased array as the radiating surface.
Such an embodiment may be steerable only in the narrow beamwidth
direction, or may be steerable in two dimensions. Such an
embodiment would have the advantage of not being limited to a small
set of quantized offset angles. Since the range of offset angles is
smaller than for a standard phased array, and since only a single
dimension is controlled, implementation issues seen in a phased
array embodiment may be eased.
[0054] Variations and alternative embodiments of implementing an
offset beam will also be apparent from the descriptions provided
herein.
[0055] For a single antenna with a fixed beam offset or a steerable
beam offset, the two way communication may then function as
follows. The asymmetric aperture antenna will include a radiating
surface, a gimbal with an azimuth adjustment and an elevation
adjustment; and a signal source that provides a signal to the
radiating surface. The beam offset may be fixed or controllable as
described above based on the mechanism for providing a signal from
a signal source to the radiating surface. The beam offset thus
essentially describes an offset from a perpendicular of the
radiating surface at which an offset antenna beam pattern radiates.
The offset beam pattern is set or fixed to reduce interference with
an adjacent satellite when the gimbal directs the antenna beam
pattern toward a target satellite.
[0056] For controllable beam offsets, the beam offset may be
programmed or set in conjunction with control circuitry that may
adjust the beam offset over time as the antenna moves, in order to
minimize interference with adjacent satellites while maintaining
acceptable transmission and reception characteristics. Such a
system may include a positioning system that uses satellite global
positioning signals to determine the appropriate offset, or may
receive a signal from navigation systems of the vehicle on which
the antenna is mounted. In such embodiments, the antenna may
include or be coupled with a local computing device that stores
instructions for antenna operation, such as the computing devices
described in FIG. 6.
[0057] In still further embodiments, one or more
asymmetric-aperture antennas having a beam offset as described
herein may receive control information via a remote or wide area
network. In some embodiments, for example, an initial communication
protocol may establish an initial satellite communication using a
first protocol that avoids adjacent satellite interference but
using a lower bandwidth communication. Instructions for a beam
pattern offset may then be received for the appropriate beam offset
for communicating with a target satellite, and additional
instructions for controlling the beam offset may be received via
the target satellite. Such instructions may be updated over time by
the target satellite or the initial communication means if
communication with the target satellite is lost. Control circuitry
that sets the beam offset may then be programmed or structured to
set an appropriate beam offset to reduce adjacent satellite
interference.
[0058] Further still, in certain embodiments, networks of multiple
asymmetric aperture antennas may be controlled remotely or in a
hybrid manner, with certain local controls and certain centralized
and synchronized remote network controls from a system of multiple
antennas. FIG. 5, for example, illustrates one potential method of
implementing a system of multiple asymmetric-aperture antennas
according to one potential embodiment.
[0059] In 504, boundaries of preferred deployment are identified
based on interference standards that may be governmental standards
or communication system quality standards, are identified for one
or more satellites and the adjacent satellites for each satellite.
As such, a system may be not only for a single target satellite,
but for multiple target satellites and antennas associated with
each satellite. In certain embodiments, a single antenna may
communicate with multiple target satellites, with a different beam
offset for each satellite, for example.
[0060] In 506, The antenna beam pattern for one or more antennas
operating in the system are adjusted to one or more different beam
angles as described above in detail. The beam patterns are adjusted
to offset angles with respect to the plane of the radiating surface
in the narrow beamwidth direction, thus offsetting the beam in the
azimuth direction, and creating an offset beam for each antenna. In
certain embodiments, the offset is in the narrow beamwidth only,
with no elevation offset in the wide beamwidth direction. In other
embodiments, the offset may be in two directions, both the wide and
narrow beamwidth directions.
[0061] Following this, in 508 a gimbal mechanism of the
asymmetric-aperture antenna that adjusts the position of the
radiating surface to direct the offset beam to the appropriate
target satellite. For certain embodiments, such as embodiments with
a fixed and set beam pattern offset, the method of operating the
system may then simply be set, with no additional variation.
[0062] In the embodiment of FIG. 5, 510 follows with a feedback
step, where actual performance degradation from the skew angle
adjustment that creates the offset beam pattern may be measured or
calculated. One potential performance degradation is a loss in
antenna gain due to the beam width changes. Additionally, higher
scan loss may occur due to secondary considerations with the offset
beam pattern, and the system may have higher noise due to
additional network complexities. This may additionally be
compensated for during calculation of the offset. In various
embodiments, the selected offset for a given antenna, group of
antennas, or antenna in a particular position may be determined not
only based on the interference reduction from the offset beam
pattern, but also based on any performance degradation.
[0063] Finally, in 512, the two-way communication system operates
with communications between one or more satellites and the one or
more asymmetric-aperture antennas using the antennas with offset
beams and any additional performance parameters to operate the
system.
[0064] FIG. 7 describes one potential implementation of an antenna
control system according to one embodiment. FIG. 7 includes antenna
720, remote server 750, and network 760. Antenna 720 includes
controller 850, memory 860, network interface module 870, sensors
880, beam offset circuitry 828, azimuth adjustment module 824,
elevation adjustment module 826, mechanical gimbal 820, and
radiating surface 827.
[0065] Sensors 880 may be any local transceiver or information
gathering device that may be used by the antenna 720 to determine
information relevant to the setting of the beam direction from
radiating surface 827 and the mechanical gimbal 820. For example,
sensors 880 may include location services such as a global
positioning device that determines a current location of antenna
720. In an alternative embodiment, sensors 880 include an inertial
reference unit (IRU) that determines a vehicle location and/or
orientation.
[0066] Controller 850, memory 860, and network interface module 870
may function as electronic control components, as described in
additional detail in FIG. 6 below. These components may serve to
implement control instructions to set the direction and beam
properties of radiating surface 827 of antenna 720 using beam
offset circuitry 828, azimuth adjustment module 824, and elevation
adjustment module 826. Mechanical gimbal 820 may be physically
coupled to radiating surface 827 such that as the components of
mechanical gimbal 820 adjust and move, the radiating surface 827 is
directed to the appropriate location. Elevation adjustment module
826 and azimuth adjustment module 824 may receive electronic
control signals to direct the mechanical gimbal 820 to move
radiating surface 827 to this appropriate location. The two
adjustment modules may receive instructions related to the
appropriate settings from controller 850. These settings may be
from a control program stored in memory 860, or may be received
from remote server 750 via network 760 and network interface module
870 if the antenna is being controlled from a server remotely.
[0067] For example, in the embodiment of FIG. 1 with satellite 110,
adjacent satellites 112a and 112b, and asymmetric aperture antenna
140, regulatory standards may set a maximum amount of signal that
may be directed from asymmetric aperture antenna 140 to adjacent
satellites 112a and 112b. Such information may be used to create a
predetermined adjacent satellite interference threshold. Thus, in
such a system where antenna 140 includes the internal antenna
structure of antenna 720, memory 860 may store location details for
satellite 110 and adjacent satellites 112a and 112b, along with the
value for the adjacent satellite interference threshold.
[0068] Additionally, for an asymmetric-aperture antenna mounted to
an airplane such as antenna 140, controller 850 may continually
update a position of the antenna 140. Memory 860 may also include
antenna beam characteristics associated with antenna 140. The
current location of the antenna 140 along with the stored
information for satellite 110 will enable the controller 850 to
calculate the central vector for the antenna beam pattern to point
at satellite 110. This may be done approximately by, for example,
using a look-up table stored in memory 860 or this calculation may
be performed using the stored location data. The antenna beam
characteristics stored in memory 860, along with the current
position of the antenna 140 and the locations of adjacent
satellites 112a and 112b, will enable controller 850 to calculate a
beam offset angle and new azimuth and elevation angles that will
place the adjacent satellite interference below the adjacent
satellite interference threshold. The angles may be precomputed and
the results stored in a table, to be looked up as needed in real
time. Alternatively, the calculation itself may be done in real
time.
[0069] Once the controller calculates the beam offset angle, the
beam offset circuitry 828 controls an input to radiating surface
827 to set the corresponding beam offset angle during operation. If
the antenna is a phased array antenna, the beam offset circuitry
828 will set antenna element phases to accomplish the desired
offset. Alternatively, if the antenna is stepwise steerable, the
beam offset circuitry 828 will select a desired offset from the
available steps. As an example in one potential embodiment, this
may be done by setting appropriate switches associated with the
antenna to select the beam offset angle. In association with the
change in offset angle by the beam offset circuitry 828, the
controller 850 directs azimuth adjustment module 824 and elevation
adjustment module 826 to control the mechanical gimbal 820 such
that the central vector for the offset antenna beam pattern points
at satellite 110. During operation, this process may be repeated
continuously or at predetermined time or location increments, so
that as the vehicle associated with antenna 140 travels, the
adjacent satellite interference may remain within the acceptable
threshold.
[0070] In additional alternative embodiments, calculation of the
settings may be performed by remote servers such as remote server
750, and communicated via network 760. In further embodiments, any
of the modules or components described in antenna 720 may be
implemented as separate components or may be integrated together.
Additionally, the modules, memory, controller, and sensors of an
antenna may be disposed separately from an antenna and coupled
communicatively to the physical components of the antenna.
[0071] In certain embodiments, beam offset circuitry 828 may
comprise electronic control of an antenna signal to create the
offset beam pattern. In alternative embodiments, beam offset
circuitry 828 may comprise electronic control of a physical
component of the antenna, where altering the physical component of
the antenna creates the beam offset pattern. In further alternative
embodiments, beam offset circuitry 828 may comprise a fixed
mechanical structure in the system that is not electronically
controllable and which sets a fixed beam offset. In such
embodiments, the system may be created to calculate the adjacent
satellite interference, and to halt antenna transmissions when the
adjacent satellite interference exceeds an adjacent satellite
interference threshold.
[0072] FIG. 8 describes one potential implementation of elements of
an low profile asymmetric-aperture antenna according to certain
embodiments. FIG. 8 may, in certain embodiments, show elements that
may function as beam offset circuitry 828 and radiating surface
827. FIG. 8 includes signal source 905, amplifier 910, a radiating
surface 927, and a plurality of splitters 921, 922a-b, and 924a-d.
Radiating surface 927 comprises a plurality of radiating elements
930a-933b. Signal source 905 is connected to each of the plurality
of radiating elements by various combinations of lines 940a-b,
944a-d, 950a-b, 951a-b, 952a-b, and 953a-b.
[0073] Signal source 905 may be any source that provides
information to be transmitted by the antenna using radiating
surface. For example, signal source 905 may be a modem that
includes modulation and demodulation functionality for
communicating information to a satellite via a radiating surface.
In various embodiments this may be part of a multi-purpose
controller that implements antenna control and signal communication
systems such as communication subsystem 630 of FIG. 6 or controller
850 of FIG. 7. In alternate embodiments, a specialized modem module
may be implemented as signal source 905. Amplifier 910 may be a
power amplifier that accepts information for transmission and
amplifies the signal to a sufficient strength to be communicated to
a target satellite using radiating surface 927. The circuitry
between amplifier 910 and radiating surface 927 may then function
both to provide the signal to the radiating elements of radiating
surface 927, and also to set an offset for the radiating beam. As
described above, this offset may be created by a variation in the
phase of signals arriving at the radiating elements, such that a
constant gradient of signal phase is presented across a planar
array of radiating elements. The embodiment of FIG. 8 shows a 2 by
4 array of radiating elements in columns a and b and rows 930-933.
In alternate embodiments, any number of one or more radiating
element columns or two or more radiating element rows may be
structured according to various embodiments. At least two radiating
elements are required along the long axis of the radiating surface
to enable the offset in the narrow-beamwidth direction.
[0074] Lines 940a-b, 944a-d, 950a-b, 951a-b, 952a-b, and 953a-b may
then be fixed to determine the offset in the narrow-beamwidth
direction from the perpendicular of the radiating surface. This may
be done by adjusting the difference in electrical path length from
amplifier 910 to each row of radiating elements. Thus, the path
including line 940a, line 944a, and line 950a may have an
electrical path length "L". The final lengths to each row may have
a same length, with line 950b having the same electrical length as
line 950a so that the phase at radiating elements 930a and 930b is
the same. Similarly the lengths of lines 951a-b are the same, the
lengths of lines 952a-b are the same, and the lengths of lines
953a-b are the same, so that each row of elements has the same
phase offset. The path including line 940a, line 944b, and line
951a may have a length "L+a". The path including line 940b, line
944c, and line 952a may have a length of "L+2a." The path including
line 940b, line 944d, and line 953a may have a length of "L+3a."
The value of "a" may set the constant gradient of phase across the
array, and may thus set the beam offset in the narrow-beamwidth
direction. Any number of combination of line lengths for lines
940a-b, 944a-d, 950a-b, 951a-b, 952a-b, and 953a-b may be set to
achieve this result. In certain embodiments, the offset and
associated constant gradient of signal delays is set by a total
length of the transmission lines for each electrical path of the
plurality of electrical paths, while in other embodiments, delay
components may be included in certain lines to achieve the desired
offset at certain radiating elements independent of a physical
length of the transmission lines.
[0075] The embodiment above thus describes an antenna with a fixed
beam offset in the narrow-beamwidth direction only. In alternate
embodiments, a phase difference between radiating elements in the
same rows may be included that sets a beam offset in the-wide
beamwidth direction. This may influence loss calculations for
embodiments where the loss is optimized against the adjacent
satellite interference. The adjacent satellite interference,
however, is reduced only by the offset in the narrow beam width
direction.
[0076] FIG. 9 shows an additional alternative implementation of an
antenna according to various embodiments. While the embodiment of
FIG. 8 shows a fixed offset antenna that is determined by the
electrical path lengths of lines delivering signals to each
radiating element, the embodiment of FIG. 9 shows one potential
implementation of an antenna with an adjustable beam offset. FIG. 9
includes signal source 1005, amplifier 1010, switching circuit
1014, offset control 1012, Rotman Lens 1020, and radiating surface
1027. Radiating surface 1027 comprises a plurality of radiating
elements 1030 through 1035 as shown. signal source 1005 and
amplifier 1010 may function similarly to the source and amplifier
described above in FIG. 8. At the output of amplifier 1010,
however, the signal is input into a switching circuit 1014. The
switching circuit selects between a plurality of input ports to
Rotman lens 1020. Each port of the plurality of input ports to
Rotman lens 1020 selects a different set of delays for the signal
from signal source 1005 to each radiating element of radiating
surface 1027. This enables the switch 1014 to select from a set of
predetermined offsets in the narrow beamwidth direction for a beam
radiated from radiating surface 1027.
[0077] Thus, while the example of FIG. 8 shows a single set of
signal delays to each radiating element, the example of FIG. 9 may
include multiple sets of signal delays to each radiating element.
Each set of signal delays is associated with a different constant
gradient of signal delays that sets a different beam offset. Offset
control 1012 may then select the different beam offsets to adapt to
different needs for reducing adjacent satellite interference. This
may enable a single antenna to operate in different systems where a
plurality of antennas in a system communicating with a specific
target satellite all have the same offset in the narrow beamwidth
direction. Alternatively, this may enable a single antenna to
switch between adjacent satellite interference settings depending
on different operating modes within a single system. As described
above, these selections by offset control 1012 may be made by an
application or module operating on a controller or processor of an
antenna, or the selections may be received from a remote computing
system using a wireless communication, as shown in FIG. 7.
[0078] FIG. 10 shows one potential embodiment of an electronically
steerable one dimensional phased array that may be used to set an
offset in the narrow beamwidth direction of an asymmetric aperture
antenna having a radiating surface 1127 with a one dimensional
array of radiating elements 1130-1133. FIG. 10 further includes
signal source 1105, amplifier 1111, splitters 1121, 1122a, and
1122b, along with phase shifting elements 1124a-d, amplifiers
1160-1163, and offset control 1112. The various elements are
connected by lines 1140a-b, 1144a-d, and 1150-1153. Signal source
1105, amplifier 1111, radiating surface 1127, and splitters 1121,
1122a, and 1122b may be similar to the corresponding components
found in FIGS. 8 and 9. Amplifiers 1160-1163 may be connected to
radiating elements 1130-1133 in order to deal with various design
considerations, such as power limitations or a loss in phase
shifting elements and splitters, or to deal with non-linear effects
in the circuitry that delivers signals to individual radiating
elements.
[0079] The antenna of FIG. 10 includes phase shifting elements
1124a-1124b. Offset control 1112 may electronically set a phase
shift associated with each phase shifting element 1124, so that the
phase shift associated with each element may be electronically
controlled to change over time. Thus, the gradient of phase
differences achieved by the phase at each individual radiating
element of the plurality of radiating elements 1130-1133 may be
electronically adjusted. The fineness of the control may depend
completely on the detail of the phase shift allowed in the phase
shifting elements 1124, but may enable a control to small fractions
of a degree in the offset from the normal in the narrow beamwidth
direction. As shown in FIG. 10, radiating surface only includes a
single column of radiating elements. In such an embodiment, the
offset of the beam may only be in the narrow beamwidth direction,
because there is no phase difference across any rows that would set
an offset in a wide beamwidth direction. In embodiments with a two
dimensional array of radiating elements, the offset may be
structured to be controllable in the wide-beamwidth direction as
well as the narrow beamwidth direction if each radiating element,
including radiating elements in the same row, each have a
separately controllable phase shifting element. In alternative
embodiments, a single phase shifting element may be assigned to an
entire row, with splitters following the phase shifting elements to
connect signal lines to radiating elements in the same row, in
order to structure a two dimensional array of radiating elements in
asymmetric aperture antenna with an electronically steerable offset
control in the narrow beamwidth direction only.
[0080] Thus, while in the antenna of FIG. 8 the offset is fixed by
the electrical path lengths to each radiating element, and in FIG.
9, a limited number of offsets are fixed by the design of the
Rotman lens, in FIG. 10, a large number of continuous offsets may
be controlled at set by a processor of the antenna or by a remote
control system that may be in a different location than the
antenna, where a remote server 750 may update and set the offset
along a finely defined electronically controlled offset setting. In
other embodiments, a computing element coupled to an antenna may
calculate inter satellite interference in different situations, and
use offset control 1112 to set an acceptable offset to match
specifically calculated inter satellite interference
thresholds.
[0081] While three specific examples of antennas that may have an
beam offset from the perpendicular of a radiating surface in the
narrow beamwidth direction are described above, with one example of
a fixed offset shown in FIG. 8, one example of a stepwise-steerable
offset using a Rotman lens shown in FIG. 9, and one example of an
electronically steerable offset using phase shifting elements,
other designs may function to create such an offset which may be
used to reduce inter satellite interference. For example,
alternative embodiments may use multiple Rotman lenses in a single
antenna, or may use other electronically adjustable means for
steering the beam offset. Additional embodiments may include other
embodiments of electronically steerable phased arrays for an
asymmetric aperture antenna that is steerable in the narrow
beamwidth direction. Any potential such antennas may be used in a
system for reducing adjacent satellite interference in accordance
with different embodiments.
[0082] Further still, while the embodiments herein may be described
with respect to interference in transmission from a radiating
surface to a satellite to avoid interference with an adjacent
satellite, similar embodiments may be used to reduce interference
from an adjacent satellite when receiving a signal from a target
satellite. For example, in a receiver of the antenna shown in FIG.
10, a controller analyzing received signals may determine that
interfering signals from a satellite adjacent to a target satellite
is causing an excessive number of errors in the signal received
from the target satellite. The antenna may then adjust phase
shifting elements on lines from an array of receiving elements
which may be the same as the radiating elements. This may adjust an
offset in the narrow beamwidth direction for a received signal,
which reduces the received signal from the adjacent satellite when
a mechanical gimbal directs the offset receiving beam toward the
target satellite. This receiving beam, which may be considered a
receiving beam pattern similar to the transmit beam pattern
described above, the receiving beam pattern being of sensitivity
for received signals at an antenna surface, may thus be adjusted to
reduce inter satellite interference for received signals by setting
phase on the receiving lines to offset the receiving beam in the
narrow beamwidth direction, and by then directing this receiving
beam toward the target satellite.
[0083] FIG. 6 provides a schematic illustration of one embodiment
of a computer system 600 that can perform the methods of the
invention, as described herein, and/or can function, for example,
as any part of a control module, communication module, or satellite
module as described herein. It should be noted that FIG. 6 is meant
only to provide a generalized illustration of various components,
any or all of which may be utilized, as appropriate. FIG. 6,
therefore, broadly illustrates how individual system elements may
be implemented in a relatively separated or relatively more
integrated manner.
[0084] The computer system 600 is shown comprising hardware
elements that can be electrically coupled via a bus 605 (or may
otherwise be in communication, as appropriate). The hardware
elements can include one or more processors 610, including, without
limitation, one or more general-purpose processors and/or one or
more special-purpose processors (such as digital signal processing
chips, graphics acceleration chips, and/or the like); one or more
input devices 615, which can include, without limitation, a mouse,
a keyboard, and/or the like; and one or more output devices 620,
which can include, without limitation, a display device, a printer,
and/or the like.
[0085] The computer system 600 may further include (and/or be in
communication with) one or more storage devices 625, which can
comprise, without limitation, local and/or network accessible
storage and/or can include, without limitation, a disk drive, a
drive array, an optical storage device, a solid-state storage
device such as a random access memory ("RAM"), and/or a read-only
memory ("ROM"), which can be programmable, flash-updateable, and/or
the like. The computer system 600 might also include a
communications subsystem 630, which can include, without
limitation, a modem, a network card (wireless or wired), an
infrared communication device, a wireless communication device
and/or chipset (such as a Bluetooth.TM. device, an 802.11 device, a
Wi-Fi device, a WiMax device, cellular communication facilities,
etc.), and/or the like. The communications subsystem 630 may permit
data to be exchanged with a network (such as the network described
below, to name one example), and/or any other devices described
herein. In many embodiments, the computer system 600 will further
comprise a working memory 635, which can include a RAM or ROM
device, as described above.
[0086] In certain embodiments, communications subsystem 630 may
include a modem that may receive information for transmission via a
satellite communications system. Such a modem system as part of
communications subsystem 630 may include a
modulator/demodulator-provides a modulated signal to an antenna and
demodulates signals received at an antenna from a satellite
communications system.
[0087] The computer system 600 also can comprise software elements,
shown as being currently located within the working memory 635,
including an operating system 640 and/or other code, such as one or
more application programs 645, which may comprise computer programs
of the invention and/or may be designed to implement methods of the
invention and/or configure systems of the invention, as described
herein. Merely by way of example, one or more procedures described
with respect to the method(s) discussed above might be implemented
as code and/or instructions executable by a computer (and/or a
processor within a computer). A set of these instructions and/or
code might be stored on a computer readable storage medium, such as
the storage device(s) 625 described above. In some cases, the
storage medium might be incorporated within a computer system, such
as the system 600. In other embodiments, the storage medium might
be separate from a computer system (i.e., a removable medium, such
as a compact disc, etc.), and/or provided in an installation
package, such that the storage medium can be used to program a
general purpose computer with the instructions/code stored thereon.
These instructions might take the form of executable code, which is
executable by the computer system 600, and/or might take the form
of source and/or installable code which, upon compilation and/or
installation on the computer system 600 (e.g., using any of a
variety of generally available compilers, installation programs,
compression/decompression utilities, etc.), then takes the form of
executable code.
[0088] It will be apparent to those skilled in the art that
substantial variations may be made in accordance with specific
requirements. For example, customized hardware might also be used,
and/or particular elements might be implemented in hardware,
software (including portable software, such as applets, etc.), or
both. Further, connection to other computing devices such as
network input/output devices may be employed.
[0089] In one aspect, the invention employs a computer system (such
as the computer system 600) to perform methods of the invention.
According to a set of embodiments, some or all of the procedures of
such methods are performed by the computer system 600 in response
to processor 610 executing one or more sequences of one or more
instructions (which might be incorporated into the operating system
640 and/or other code, such as an application program 645)
contained in the working memory 635. Such instructions may be read
into the working memory 635 from another machine-readable medium,
such as one or more of the storage device(s) 625. Merely by way of
example, execution of the sequences of instructions contained in
the working memory 635 might cause the processor(s) 610 to perform
one or more procedures of the methods described herein.
[0090] The terms "machine-readable medium" and "computer readable
medium", as used herein, refer to any medium that participates in
providing data that causes a machine to operate in a specific
fashion. In an embodiment implemented using the computer system
600, various machine-readable media might be involved in providing
instructions/code to processor(s) 610 for execution and/or might be
used to store and/or carry such instructions/code (e.g., as
signals). In many implementations, a computer readable medium is a
physical and/or tangible storage medium. Such a medium may take
many forms, including, but not limited to, non-volatile media,
volatile media, and transmission media. Non-volatile and
non-transitory media includes, for example, optical or magnetic
disks, such as the storage device(s) 625. Volatile media includes,
without limitation, dynamic memory, such as the working memory 635.
Transmission media includes coaxial cables, copper wire, and fiber
optics, including the wires that comprise the bus 605, as well as
the various components of the communications subsystem 630 (and/or
the media by which the communications subsystem 630 provides
communication with other devices). Hence, transmission media can
also take the form of waves (including, without limitation, radio,
acoustic, and/or light waves, such as those generated during
radio-wave and infrared data communications).
[0091] Common forms of physical and/or tangible computer readable
media include, for example, a floppy disk, a flexible disk, hard
disk, magnetic tape, or any other magnetic medium, a CD-ROM, any
other optical medium, punchcards, papertape, any other physical
medium with patterns of holes, a RAM, a PROM, an EPROM, a
FLASH-EPROM, any other memory chip or cartridge, a carrier wave as
described hereinafter, or any other medium from which a computer
can read instructions and/or code.
[0092] Various forms of machine-readable media may be involved in
carrying one or more sequences of one or more instructions to the
processor(s) 610 for execution. Merely by way of example, the
instructions may initially be carried on a magnetic disk and/or
optical disc of a remote computer. A remote computer might load the
instructions into its dynamic memory and send the instructions as
signals over a transmission medium to be received and/or executed
by the computer system 600. These signals, which might be in the
form of electromagnetic signals, acoustic signals, optical signals,
and/or the like, are all examples of carrier waves on which
instructions can be encoded, in accordance with various embodiments
of the invention.
[0093] The communications subsystem 630 (and/or components thereof)
generally will receive the signals, and the bus 605 then might
carry the signals (and/or the data, instructions, etc., carried by
the signals) to the working memory 635, from which the processor(s)
605 retrieves and executes the instructions. The instructions
received by the working memory 635 may optionally be stored on a
storage device 625 either before or after execution by the
processor(s) 610.
[0094] Also, it is noted that the embodiments may be described as a
process which is depicted as a flowchart, a flow diagram, a data
flow diagram, a structure diagram, or a block diagram. Although a
flowchart may describe the operations as a sequential process, many
of the operations can be performed in parallel or concurrently. In
addition, the order of the operations may be re-arranged. A process
is terminated when its operations are completed, but could have
additional steps not included in the figure. A process may
correspond to a method, a function, a procedure, a subroutine, a
subprogram, etc. When a process corresponds to a function, its
termination corresponds to a return of the function to the calling
function or the main function.
[0095] Furthermore, embodiments may be implemented by hardware,
software, scripting languages, firmware, middleware, microcode,
hardware description languages, and/or any combination thereof.
When implemented in software, firmware, middleware, scripting
language, and/or microcode, the program code or code segments to
perform the necessary tasks may be stored in a machine readable
medium such as a storage medium. A code segment or
machine-executable instruction may represent a procedure, a
function, a subprogram, a program, a routine, a subroutine, a
module, a software package, a script, a class, or any combination
of instructions, data structures, and/or program statements. A code
segment may be coupled to another code segment or a hardware
circuit by passing and/or receiving information, data, arguments,
parameters, and/or memory contents. Information, arguments,
parameters, data, etc. may be passed, forwarded, or transmitted via
any suitable means including memory sharing, message passing, token
passing, network transmission, etc.
[0096] In various embodiments, control and computer devices
described in FIG. 6 above may be networked together to implement
various aspects of the embodiments. In one embodiment, a proxy
server and/or client may be implemented in conjunction with the
satellite communication system and offset controls as computer
system 600 in FIG. 6 as part of a communication including a
satellite such as satellite 110 of FIG. 1. Such a communication
system can include one or more system computers in networked
communications. The computers can be general purpose personal
computers (including, merely by way of example, personal computers
and/or laptop computers running any appropriate flavor of
Windows.RTM. operating systems and/or Mac OS.RTM. operating system
software) and/or workstation computers running any of a variety of
commercially-available UNIX.RTM. or UNIX-like operating systems.
These user computers may also have any of a variety of
applications, including one or more applications configured to
perform methods of the embodiments, as well as one or more control,
reporting measuring, or power management, or other computing
applications. Any number of computers can be supported by such a
system.
[0097] Certain embodiments operate in a networked environment. The
network can be any type of network familiar to those skilled in the
art that can support data communications using any of a variety of
commercially-available protocols, including, without limitation,
TCP/IP, SNA, IPX, AppleTalk.RTM., and the like. Merely by way of
example, the network can be a local area network (LAN), including,
without limitation, an Ethernet network; a Token-Ring network
and/or the like; a wide-area network (WAN); a virtual network,
including, without limitation, a virtual private network (VPN); the
Internet; an intranet; an extranet; a public switched telephone
network (PSTN); an infrared network; a wireless network, including,
without limitation, a network operating under any of the IEEE
802.11 suite of protocols, the Bluetooth.TM. protocol known in the
art, and/or any other wireless protocol; and/or any combination of
these and/or other networks.
[0098] Embodiments of the invention can include one or more server
computers. Each of the server computers may be configured with an
operating system, including, without limitation, any of those
discussed above, as well as any commercially (or freely) available
server operating systems. Each of the servers may also be running
one or more applications, which can be configured to provide
services or communication information to a device, control module,
or antenna operating according to various embodiments described
herein.
[0099] The server computers, in some embodiments, might include one
or more application servers, which can include one or more
applications accessible by a client running on one or more of the
client computers and/or other servers. Merely by way of example,
the server(s) can be one or more general purpose computers capable
of executing programs or scripts in response to the user computers
1505 and/or other servers 1515, including, without limitation, web
applications (which might, in some cases, be configured to perform
methods of the invention). Merely by way of example, a web
application can be implemented as one or more scripts or programs
written in any suitable programming language, such as Java, C, C#
or C++, and/or any scripting language, such as Perl, Python, or
TCL, as well as combinations of any programming/scripting
languages. The application server(s) can also include database
servers, including without limitation those commercially available
from Oracle.RTM., Microsoft.RTM., Sybase IBM.RTM., and the like,
which can process requests from clients (including, depending on
the configurator, database clients, API clients, web browsers,
etc.) running on a first computer and/or another server. Data
provided by an application server may be formatted as web pages
(comprising HTML, JavaScript, etc., for example) and/or may be
forwarded to a computer via a web server (as described above, for
example). In some cases a web server may be integrated with an
application server.
[0100] In accordance with further embodiments, one or more servers
can function as a file server and/or can include one or more of the
files (e.g., application code, data files, etc.) necessary to
implement methods of an embodiment incorporated by an application
running on a computer and/or another server. Alternatively, as
those skilled in the art will appreciate, a file server can include
all necessary files, allowing such an application to be invoked
remotely by a computer, antenna control module, and/or server. It
should be noted that the functions described with respect to
various servers herein (e.g., application server, database server,
file server, etc.) can be performed by a single server and/or a
plurality of specialized servers, depending on
implementation-specific needs and parameters.
[0101] In certain embodiments, the system can include one or more
databases. The location of the database(s) is discretionary: merely
by way of example, a database might reside on a storage medium
local to (and/or resident in) a server in a fixed location and
communicate to mobile antennas via a satellite such as satellite
110 of FIG. 1. Alternatively, a database can be remote and/or
mobile in relation to any of the computers or servers, so long as
the database can be in communication with one or more of these. For
example, the database may reside on a mobile server farm located on
an ocean going ship. In a particular set of embodiments, a database
can reside in a storage-area network (SAN) familiar to those
skilled in the art. Likewise, any necessary files for performing
the functions attributed to the computers or servers can be stored
locally on the respective computer and/or remotely, as appropriate.
In one set of embodiments, the database can be a relational
database, such as an Oracle database, that is adapted to store,
update, and retrieve data in response to SQL-formatted commands.
The database might be controlled and/or maintained by a database
server, as described above, for example.
[0102] Further, certain portions of embodiments (e.g., method
steps) may be described as being implemented "as a function of"
other portions of embodiments. This and similar phraseologies, as
used herein, intend broadly to include any technique for
determining one element partially or completely according to
another element. For example, a method may include setting an
antenna beam offset position "as a function of" an adjacent
satellite location and/or movement of the antenna. In various
embodiments, the determination may be made in any way, so long as
the outcome of the determination generation step is at least
partially dependent on the outcome of the fingerprint generation
step.
[0103] While the invention has been described with respect to
exemplary embodiments, one skilled in the art will recognize that
numerous modifications are possible. For example, the methods and
processes described herein may be implemented using hardware
components, software components, and/or any combination thereof.
Further, while various methods and processes described herein may
be described with respect to particular structural and/or
functional components for ease of description, methods of the
invention are not limited to any particular structural and/or
functional architecture but instead can be implemented on any
suitable hardware, firmware, and/or software configurator.
Similarly, while various functionalities are ascribed to certain
system components, unless the context dictates otherwise, this
functionality can be distributed among various other system
components in accordance with different embodiments of the
invention.
[0104] Moreover, while the procedures comprised in the methods and
processes described herein are described in a particular order for
ease of description, unless the context dictates otherwise, various
procedures may be reordered, added, and/or omitted in accordance
with various embodiments of the invention. Moreover, the procedures
described with respect to one method or process may be incorporated
within other described methods or processes; likewise, system
components described according to a particular structural
architecture and/or with respect to one system may be organized in
alternative structural architectures and/or incorporated within
other described systems. Hence, while various embodiments are
described with--or without--certain features for ease of
description and to illustrate exemplary features, the various
components and/or features described herein with respect to a
particular embodiment can be substituted, added, and/or subtracted
from among other described embodiments, unless the context dictates
otherwise. Consequently, although the invention has been described
with respect to exemplary embodiments, it will be appreciated that
the invention is intended to cover all modifications and
equivalents within the scope of the following claims.
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