U.S. patent application number 12/793485 was filed with the patent office on 2010-09-23 for radioterminals and operating methods for communicating using spectrum allocated to another satellite operator.
This patent application is currently assigned to ATC Technologies, LLC. Invention is credited to Peter D. Karabinis.
Application Number | 20100240362 12/793485 |
Document ID | / |
Family ID | 36570341 |
Filed Date | 2010-09-23 |
United States Patent
Application |
20100240362 |
Kind Code |
A1 |
Karabinis; Peter D. |
September 23, 2010 |
RADIOTERMINALS AND OPERATING METHODS FOR COMMUNICATING USING
SPECTRUM ALLOCATED TO ANOTHER SATELLITE OPERATOR
Abstract
A method of providing communications can be provided by at least
one space-based and/or terrestrial component of a first
system/operator transmitting/receiving information using spectrum
allocated to a second system/operator at an aggregate interference
level at a space-based component of the second system/operator that
is less than or substantially equal to a predetermined threshold.
Related other methods, systems, and radioterminals are also
disclosed.
Inventors: |
Karabinis; Peter D.; (Cary,
NC) |
Correspondence
Address: |
MYERS BIGEL SIBLEY & SAJOVEC
PO BOX 37428
RALEIGH
NC
27627
US
|
Assignee: |
ATC Technologies, LLC
|
Family ID: |
36570341 |
Appl. No.: |
12/793485 |
Filed: |
June 3, 2010 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11355639 |
Feb 16, 2006 |
7756490 |
|
|
12793485 |
|
|
|
|
60659463 |
Mar 8, 2005 |
|
|
|
Current U.S.
Class: |
455/427 ;
455/63.1 |
Current CPC
Class: |
H04B 7/18513 20130101;
H04B 7/195 20130101; H04W 16/14 20130101; H04B 7/18563 20130101;
H04W 84/06 20130101 |
Class at
Publication: |
455/427 ;
455/63.1 |
International
Class: |
H04W 72/04 20090101
H04W072/04 |
Claims
1. A radioterminal comprising: a transmitter/receiver circuit
configured to transmit/receive information to/from a terrestrial
component of a first system/operator using spectrum that is
allocated to a first space-based component of the first
system/operator and using spectrum that is allocated to a second
space-based component of a second system/operator.
2. A radioterminal according to claim 1 further comprising a
baseband processor circuit configured to provide data to/from the
transmitter/receiver circuit.
3. A radioterminal according to claim 2 wherein an aggregate
interference controller is configured to adjust at least one
parameter associated with the radioterminal to maintain an
aggregate interference to be less than or substantially equal to a
predetermined threshold.
4. A radioterminal according to claim 3 wherein the aggregate
interference controller is configured to limit a number of
radioterminals, to assign a data mode to a number of radioterminals
and/or to assign a vocoder mode to a number of radioterminals.
5. A radioterminal according to claim 3 wherein the predetermined
threshold comprises a level that is specified by the International
Telecommunications Union.
6. A radioterminal according to claim 1 wherein the spectrum that
is allocated to the first space-based component of the first
system/operator and the spectrum that is allocated to the second
space-based component of the second system/operator are
non-overlapping in frequency ranges.
7. A radioterminal operating method, the method comprising:
transmitting/receiving information to/from a terrestrial component
of a first system/operator using spectrum that is allocated to a
first space-based component of the first system/operator and using
spectrum that is allocated to a second space-based component of a
second system/operator.
8. A method according to claim 7 further comprising providing data
to/from the transmitting/receiving.
9. A method according to claim 8 further comprising adjusting at
least one parameter associated with the radioterminal to maintain
an aggregate interference to be less than or substantially equal to
a predetermined threshold.
10. A method according to claim 9 wherein adjusting at least one
parameter comprises limiting transmitting by the radioterminal,
assigning a data mode to the radioterminal and/or assigning a
vocoder mode to the radioterminal.
11. A radioterminal according to claim 9 wherein the predetermined
threshold comprises a level that is specified by the International
Telecommunications Union.
12. A radioterminal according to claim 7 wherein the spectrum that
is allocated to the first space-based component of the first
system/operator and the spectrum that is allocated to the second
space-based component of the second system/operator are
non-overlapping in frequency ranges.
Description
CLAIM FOR PRIORITY
[0001] This application claims is a continuation of U.S. patent
application Ser. No. 11/355,639, filed Feb. 16, 2006, entitled
Methods, Radioterminals, and Ancillary Terrestrial Components For
Communicating Using Spectrum Allocated To Another Satellite
Operator, which itself claims priority to U.S. Provisional Patent
Application No. 60/659,463, filed Mar. 8, 2005, entitled Reusing
Spectrum of Another Satellite Operator for MSS and ATC Without
Exceeding a Coordination Threshold, the entirety of both of which
are incorporated herein by reference as if set forth fully
herein.
FIELD OF THE INVENTION
[0002] This invention relates to wireless communications systems
and methods, and more particularly to satellite and terrestrial
communications systems and methods.
BACKGROUND
[0003] Satellite communications systems and methods are widely used
for wireless communications. Satellite communications systems and
methods generally employ at least one space-based component, such
as one or more satellites, that is configured to wirelessly
communicate with a plurality of satellite radioterminals.
[0004] A satellite radioterminal communications system or method
may utilize a single antenna pattern (beam or cell) covering an
entire area served by the system. Alternatively or in combination
with the above, in cellular satellite radioterminal communications
systems and methods, multiple antenna patterns (beams or cells) are
provided, each of which can serve substantially distinct
geographical areas in the overall service region, to collectively
serve an overall satellite footprint. Thus, a cellular architecture
similar to that used in conventional terrestrial cellular/PCS
radioterminal systems and methods can be implemented in cellular
satellite-based systems and methods. The satellite typically
communicates with radioterminals over a bidirectional
communications pathway, with radioterminal communications signals
being communicated from the satellite to the radioterminal over a
downlink or forward link, and from the radioterminal to the
satellite over an uplink or return link.
[0005] The overall design and operation of cellular satellite
radioterminal systems and methods is well known to those having
skill in the art, and need not be described further herein.
Moreover, as used herein, the term "radioterminal" includes
cellular and/or satellite radioterminals with or without a
multi-line display; Personal Communications System (PCS) terminals
that may combine a radioterminal with data processing, facsimile
and/or data communications capabilities; Personal Digital
Assistants (PDA) that can include a radio frequency transceiver
and/or a pager, Internet/Intranet access, Web browser, organizer,
calendar and/or a global positioning system (GPS) receiver; and/or
conventional laptop and/or palmtop computers or other appliances,
which include a radio frequency transceiver. As used herein, the
term "radioterminal" also includes any other radiating user
device/equipment/source that may have time-varying or fixed
geographic coordinates, and may be portable, transportable,
installed in a vehicle (aeronautical, maritime, or land-based), or
situated and/or configured to operate locally and/or in a
distributed fashion at any other location(s) on earth and/or in
space. A radioterminal also may be referred to herein as a
"radiotelephone," "terminal", or "wireless user device". As used
herein, the term "space-based" component includes one or more
satellites and/or one or more other objects/platforms (e.g.,
airplanes, balloons, unmanned vehicles, space crafts, missiles,
etc.) that have a trajectory above the earth at any altitude.
Furthermore, as used herein, the term "transmitting/receiving data"
shall have the same meaning and may be used interchangeably with
the term "transmitting/receiving information."
[0006] A terrestrial network can enhance an availability,
efficiency and/or economic viability of a cellular satellite
radioterminal system by terrestrially using/reusing at least some
of the frequencies that are authorized for use and/or are used by
the cellular satellite radioterminal system. In particular, it is
known that it may be difficult for cellular satellite radioterminal
systems to reliably serve densely populated areas, because
satellite signals may be, for example, blocked by high-rise
structures and/or may not penetrate into buildings. As a result,
satellite spectrum may be underutilized or unutilized in such
areas. Terrestrial use/reuse of at least some of the satellite
system frequencies can reduce or eliminate this potential
problem.
[0007] A capacity of a hybrid system, comprising terrestrial and
satellite-based communications, configured to terrestrially
use/reuse at least some of the satellite-band frequencies, may be
higher than a corresponding satellite-only system since terrestrial
frequency reuse may be much denser than that of the satellite-only
system. In fact, capacity may be enhanced where it may be mostly
needed, i.e., in densely populated urban/industrial/commercial
areas where the signal(s) of a satellite-only system may be
unreliable. As a result, a hybrid (satellite/terrestrial cellular)
system that is configured to use/reuse terrestrially at least some
of the frequencies of the satellite band may become more
economically viable, as it may be able to serve more effectively
and reliably a larger subscriber base.
[0008] One example of terrestrial reuse of satellite band
frequencies is described in U.S. Pat. No. 5,937,332 to the present
inventor Karabinis entitled Satellite Telecommunications Repeaters
and Retransmission Methods, the disclosure of which is hereby
incorporated herein by reference in its entirety as if set forth
fully herein. As described therein, satellite telecommunications
repeaters are provided which receive, amplify, and locally
retransmit the downlink/uplink signal(s) from
satellite(s)/radioterminal(s) thereby increasing an effective
downlink/uplink margin in the vicinity of the satellite
telecommunications repeaters and allowing an increase in the
penetration of uplink and downlink signals into buildings, foliage,
transportation vehicles, and other objects which can reduce link
margin. Both portable and non-portable repeaters are provided. See
the abstract of U.S. Pat. No. 5,937,332.
[0009] Satellite radioterminals for a satellite radioterminal
system or method having a terrestrial communications capability by
terrestrially using/reusing at least some of the satellite
frequency band and using substantially the same air interface for
both terrestrial and satellite communications may be more cost
effective and/or aesthetically appealing than other alternatives.
Conventional dual band/dual mode radioterminal alternatives, such
as the well known Thuraya, Iridium and/or Globalstar dual mode
satellite/terrestrial radioterminals, duplicate some components (as
a result of the different frequency bands and/or air interface
protocols that are used for satellite and terrestrial
communications), which can lead to increased cost, size and/or
weight of the radioterminal. See U.S. Pat. No. 6,052,560 to the
present inventor Karabinis, entitled Satellite System Utilizing a
Plurality of Air Interface Standards and Method Employing Same.
[0010] U.S. Pat. No. 6,684,057, to present inventor Karabinis, and
entitled Systems and Methods for Terrestrial Reuse of Cellular
Satellite Frequency Spectrum, the disclosure of which is hereby
incorporated herein by reference in its entirety as if set forth
fully herein, describes that a satellite frequency can be reused
terrestrially by an ancillary terrestrial network even within the
same satellite cell, using interference cancellation techniques. In
particular, a system according to some embodiments of U.S. Pat. No.
6,684,057 includes a space-based component that is configured to
receive wireless communications from a first radiotelephone in a
satellite footprint over a satellite radiotelephone frequency band,
and an ancillary terrestrial network that is configured to receive
wireless communications from a second radiotelephone in the
satellite footprint over the satellite radiotelephone frequency
band. The space-based component also receives the wireless
communications from the second radiotelephone in the satellite
footprint over the satellite radiotelephone frequency band as
interference, along with the wireless communications that are
received from the first radiotelephone in the satellite footprint
over the satellite radiotelephone frequency band. An interference
reducer is responsive to the space-based component and to the
ancillary terrestrial network that is configured to reduce the
interference from the wireless communications that are received by
the space-based component from the first radiotelephone in the
satellite footprint over the satellite radiotelephone frequency
band, using the wireless communications that are received by the
ancillary terrestrial network from the second radiotelephone in the
satellite footprint over the satellite radiotelephone frequency
band.
[0011] Satellite radioterminal communications systems and methods
that may employ terrestrial use/reuse of satellite frequencies by
an Ancillary Terrestrial Network (ATN) comprising at least one
Ancillary Terrestrial Component (ATC) are also described in
Published U.S. Patent Application Nos. US 2003/0054760 to
Karabinis, entitled Systems and Methods for Terrestrial Reuse of
Cellular Satellite Frequency Spectrum; US 2003/0054761 to
Karabinis, entitled Spatial Guardbands for Terrestrial Reuse of
Satellite Frequencies; US 2003/0054814 to Karabinis et al.,
entitled Systems and Methods for Monitoring Terrestrially Reused
Satellite Frequencies to Reduce Potential Interference; US
2003/0073436 to Karabinis et al., entitled Additional Systems and
Methods for Monitoring Terrestrially Reused Satellite Frequencies
to Reduce Potential Interference; US 2003/0054762 to Karabinis,
entitled Multi-Band/Multi-Mode Satellite Radiotelephone
Communications Systems and Methods; US 2003/0153267 to Karabinis,
entitled Wireless Communications Systems and Methods Using
Satellite-Linked Remote Terminal Interface Subsystems; US
2003/0224785 to Karabinis, entitled Systems and Methods for
Reducing Satellite Feeder Link Bandwidth/Carriers In Cellular
Satellite Systems; US 2002/0041575 to Karabinis et al., entitled
Coordinated Satellite-Terrestrial Frequency Reuse; US 2002/0090942
to Karabinis et al., entitled Integrated or Autonomous System and
Method of Satellite-Terrestrial Frequency Reuse Using Signal
Attenuation and/or Blockage, Dynamic Assignment of Frequencies
and/or Hysteresis; US 2003/0068978 to Karabinis et al., entitled
Space-Based Network Architectures for Satellite Radiotelephone
Systems; U.S. Pat. No. 6,785,543 to Karabinis, entitled Filters for
Combined Radiotelephone/GPS Terminals; US 2003/0153308 to
Karabinis, entitled Staggered Sectorization for Terrestrial Reuse
of Satellite Frequencies; and US 2003/0054815 to Karabinis,
entitled Methods and Systems for Modifying Satellite Antenna Cell
Patterns In Response to Terrestrial Reuse of Satellite Frequencies,
all of which are assigned to the assignee of the present invention,
the disclosures of all of which are hereby incorporated herein by
reference in their entirety as if set forth fully herein.
[0012] Some satellite radioterminal communications systems and
methods may employ satellites that use multiple bands for
communications with radioterminals. For example, U.S. Patent
Application Publication No. US 2003/0054762 to Karabinis, cited
above, describes satellite radioterminal systems and communications
methods that include a space-based component that is configured to
communicate with radioterminals in a satellite footprint that is
divided into satellite cells. The space-based component is
configured to communicate with a first radioterminal in a first
satellite cell over a first frequency band and/or a first air
interface, and to communicate with a second radioterminal in the
first or a second satellite cell over a second frequency band
and/or a second air interface. An ancillary terrestrial network
also is provided that is configured to communicate terrestrially
with the first radioterminal over substantially the first frequency
band and/or substantially the first air interface, and to
communicate terrestrially with the second radioterminal over
substantially the second frequency band and/or substantially the
second air interface. See the Abstract of U.S. Patent Application
Publication No. US 2003/0054762.
SUMMARY
[0013] Embodiments according to the invention can provide methods,
radioterminals, and ancillary terrestrial components for
communicating using spectrum allocated to another satellite
operator. Pursuant to these embodiments, a method of providing
communications can be provided by at least one space-based and/or
terrestrial component of a first system/operator
transmitting/receiving information using spectrum allocated to a
second system/operator at an aggregate interference level at a
space-based component of the second system/operator that is less
than or substantially equal to a predetermined threshold.
[0014] In some embodiments according to the invention,
transmitting/receiving includes selecting a portion of spectrum
allocated to the second system/operator to be used for
communicating by the first system/operator and
transmitting/receiving information by the first system/operator
using the portion of spectrum allocated to the second
system/operator. In some embodiments according to the invention,
the predetermined threshold is less than or substantially equal to
6% .DELTA.T/T. In some embodiments according to the invention, the
predetermined threshold is an interference threshold specified by
the International Telecommunications Union.
[0015] In some embodiments according to the invention, the method
further includes adjusting at least one parameter associated with
transmitting/receiving information by the first system/operator
using the portion of spectrum allocated to the second
system/operator to control an interference level at the space-based
component of the second system/operator to be less than or
substantially equal to the predetermined threshold. In some
embodiments according to the invention, adjusting at least one
parameter includes limiting a number of users, assigning a data
rate for communications and/or assigning a vocoder rate for
communications. In some embodiments according to the invention,
assigning a data-rate for communications includes assigning paging
and/or low data rate communications. In some embodiments according
to the invention, the method further includes at least one
terrestrial component of the first system/operator
transmitting/receiving information using the portion of spectrum
allocated to the second system/operator.
[0016] In some embodiments according to the invention,
transmitting/receiving includes a band of spectrum for
communications by the first system/operator including a portion of
spectrum allocated to the second system/operator and a portion of
spectrum allocated to the first system/operator.
[0017] In some embodiments according to the invention,
transmitting/receiving includes a data rate that is greater
compared to a data rate associated with the paging, the data rate
for communications, the vocoder rate for communications and/or the
low data rate communications.
[0018] In some embodiments according to the invention,
transmitting/receiving includes configuring a plurality of first
radioterminals to communicate with the at least one space-based
and/or terrestrial component of the first system/operator using
spectrum allocated to the second system/operator to provide an
aggregate in-band interference level and/or configuring a plurality
of second radioterminals to communicate with the at least one
space-based and/or terrestrial component using spectrum allocated
to the first system/operator to provide an aggregate out-of-band
interference level, wherein a combination of the in-band and the
out-of-band interference levels is less than or substantially equal
to the predetermined threshold.
[0019] In some embodiments according to the invention, a method of
providing communications includes configuring a space-based
component of a first system/operator to transmit and/or receive
information using spectrum allocated to a second system/operator.
In some embodiments according to the invention, a method of
providing communications includes a space-based component of a
first system/operator transmitting/receiving information using
spectrum allocated to a second system/operator to provide an
in-band space-based interference component at a space-based
component of the second system/operator and/or at least one
terrestrial component of the first system/operator
transmitting/receiving information using spectrum allocated to the
second system/operator to provide an in-band terrestrial
interference component at the space-based component of the second
system/operator.
[0020] In some embodiments according to the invention, the in-band
space-based interference component and the in-band terrestrial
interference component at the space-based component of the second
system/operator provide an interference level that is less than or
substantially equal to 6% .DELTA.T/T.
[0021] In some embodiments according to the invention, a
space-based component of a first system/operator
transmitting/receiving information includes communicating with
relatively few users, communicating using relatively low data rate
communications and/or communicating using relatively low rate
vocoder communications.
[0022] In some embodiments according to the invention, a method of
providing communications includes a space-based component and/or at
least one terrestrial component of a first system/operator
transmitting/receiving information using spectrum allocated to a
second system/operator to allow a continuous band of spectrum for
transmitting/receiving information by the first
system/operator.
[0023] In some embodiments according to the invention, a
radioterminal includes a transmitter/receiver circuit configured to
transmit/receive information to/from a space-based component and/or
to/from at least one ancillary terrestrial component of a first
system/operator using spectrum allocated to a second
system/operator.
[0024] In some embodiments according to the invention, the
radioterminal further includes a baseband processor circuit
configured to provide data to/from the transmitter/receiver
circuit. In some embodiments according to the invention, an
aggregate interference controller is configured to adjust at least
one parameter associated with the radioterminal to maintain an
aggregate interference to be less than or substantially equal to a
predetermined threshold.
[0025] In some embodiments according to the invention, the
aggregate interference controller is configured to limit a number
of radioterminals, assign a data mode and/or a vocoder mode to
radioterminals using spectrum allocated to the second
system/operator.
[0026] In some embodiments according to the invention, the
predetermined threshold is less than or substantially equal to 6%
.DELTA.T/T at a space-based component of the second satellite
operator. In some embodiments according to the invention, the
predetermined threshold is a level that is specified by the
International Telecommunications Union.
[0027] In some embodiments according to the invention, an Ancillary
Terrestrial Network (ATN) of a first system/operator includes an
aggregate interference controller for controlling space-based
and/or terrestrial communications of the first system/operator
using spectrum allocated to a second system/operator and to
maintain an aggregate interference level at a space-based component
of the second system/operator at less than or substantially equal
to a predetermined threshold.
[0028] In some embodiments according to the invention, the
aggregate interference controller is further configured to select
at least one portion of spectrum allocated to the second
system/operator to be used by the first system/operator and
configuring radioterminals of the first system/operator to
transmit/receive information using the at least one portion of
spectrum allocated to the second system/operator.
[0029] In some embodiments according to the invention, the
predetermined threshold is less than or substantially equal to 6%
.DELTA.T/T at a space-based component of the second
system/operator. In some embodiments according to the invention,
the predetermined threshold is an interference threshold specified
by the International Telecommunications Union. In some embodiments
according to the invention, the aggregate interference controller
is further configured to adjust at least one parameter associated
with at least one radioterminal to maintain the aggregate
interference at the space-based component of the second
system/operator less than or substantially equal to the
predetermined threshold.
[0030] In some embodiments according to the invention, adjusting at
least one parameter comprises limiting a number of radioterminals,
assigning a data mode and/or assigning a vocoder mode. In some
embodiments according to the invention, the ATN further includes a
controller that configures a plurality of first radioterminals to
communicate with the space-based component and/or with the ATN of
the first system/operator using spectrum allocated to the second
system/operator to provide an aggregate in-band interference
component and/or configures a plurality of second radioterminals to
communicate with the space-based component and/or the ATN using
spectrum allocated to the first system/operator to provide an
aggregate out-of-band interference component, wherein a combination
of the aggregate in-band interference component and the aggregate
out-of-band interference component at the space-based component of
the second system/operator is less than or substantially equal to
the predetermined threshold.
[0031] In some embodiments according to the invention, a
terrestrial system is configured to transmit and/or receive
information wirelessly using at least some spectrum allocated to
another system and to maintain a level of interference at the other
system at less than or substantially equal to a predetermined
threshold.
[0032] In some embodiments according to the invention, a method of
reusing spectrum of a second system/operator by a first
system/operator includes reusing the spectrum of the second
system/operator for space-based and/or terrestrial communications
by the first system/operator at an aggregate interference level at
the second system/operator that is less than or substantially equal
to a predetermined threshold.
[0033] In some embodiments according to the invention, a
space-based component of a system is configured to transmit and/or
receive information using at least some spectrum allocated to
another system and to maintain a level of interference at the other
system that is less than or substantially equal to a predetermined
threshold.
[0034] In some embodiments according to the invention, a
radioterminal is configured to transmit/receive information to/from
an element of a first wireless system using spectrum allocated to a
second wireless system and to maintain a level of interference at
the second wireless system that is less than or substantially equal
to a predetermined threshold.
[0035] In some embodiments according to the invention, a first
wireless system is configured to transmit/receive information using
spectrum allocated to a second wireless system and to maintain a
level of interference at the second wireless system that is less
than or substantially equal to a predetermined threshold. In some
embodiments according to the invention, a method of providing
communications includes at least one component of a first
system/operator transmitting/receiving information using spectrum
allocated to a second system/operator and maintaining a level of
interference at a component of the second system/operator that is
less than or substantially equal to a predetermined threshold.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 is a schematic illustration of spectrum allocated to
first and second satellite operators.
[0037] FIG. 2 is a schematic illustration of a cellular satellite
radiotelephone system of a first satellite operator that
communicates with space based and/or terrestrial components thereof
using spectrum allocated to a second satellite operator according
to some embodiments of the invention.
[0038] FIG. 3 is a block diagram that illustrates radiotelephones
configured to communicate with space based and/or terrestrial
components according to some embodiments of the invention.
DESCRIPTION OF EMBODIMENTS ACCORDING TO THE INVENTION
[0039] Specific exemplary embodiments of the invention now will be
described with reference to the accompanying drawings. This
invention may, however, be embodied in many different forms and
should not be construed as limited to the embodiments set forth
herein. Rather, these embodiments are provided so that this
disclosure will be thorough and complete, and will fully convey the
scope of the invention to those skilled in the art. It will be
understood that when an element is referred to as being "connected"
or "coupled" to another element, it can be directly connected or
coupled to the other element or intervening elements may be
present. Furthermore, "connected" or "coupled" as used herein may
include wirelessly connected or coupled.
[0040] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a", "an" and
"the" are intended to include the plural forms as well, unless
expressly stated otherwise. It will be further understood that the
terms "includes," "comprises," "including" and/or "comprising,"
when used in this specification, specify the presence of stated
features, integers, steps, operations, elements, and/or components,
but do not preclude the presence or addition of one or more other
features, integers, steps, operations, elements, components, and/or
groups thereof.
[0041] Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
invention belongs. It will be further understood that terms, such
as those defined in commonly used dictionaries, should be
interpreted as having a meaning that is consistent with their
meaning in the context of the relevant art and the present
disclosure, and will not be interpreted in an idealized or overly
formal sense unless expressly so defined herein.
[0042] It will be understood that although the terms first and
second are used herein to describe various elements, these elements
should not be limited by these terms. These terms are only used to
distinguish one element from another element. Thus, a first
space-based component below could be termed a second space-based
component, and similarly, a second space-based component may be
termed a first space-based component without departing from the
teachings of the present invention. As used herein, the term
"and/or" includes any and all combinations of one or more of the
associated listed items. The symbol "/" is also used as a shorthand
notation for "and/or".
[0043] Moreover, as used herein, "substantially the same" band(s)
means that two or more bands being addressed/compared substantially
overlap, but that there may be some areas of non-overlap, for
example at a band end and/or elsewhere. "Substantially the same"
air interface(s) means that two or more air interfaces being
addressed/compared are similar but need not be identical. Some
differences may exist in one air interface (i.e., a satellite air
interface) relative to another (i.e., a terrestrial air interface)
to account for one or more different characteristics/concerns that
may exist between, for example, the terrestrial and satellite
communications environments. For example, a different vocoder rate
may be used for satellite communications compared to the vocoder
rate that may be used for terrestrial communications (i.e., for
terrestrial communications, voice may be compressed ("vocoded") to
approximately 9 to 13 kbps, whereas for satellite communications a
vocoder rate of approximately 2 to 4 kbps, for example, may be
used); a different forward error correction coding, different
interleaving depth, and/or different spread-spectrum codes may also
be used, for example, for satellite communications compared to the
coding, interleaving depth, and/or spread spectrum codes (i.e.,
Walsh codes, long codes, and/or frequency hopping codes) that may
be used for terrestrial communications.
[0044] Some embodiments of the present invention may arise from a
recognition that spectrum used and/or authorized for use by another
system/operator may be reused by a given system/operator, provided
that an intersystem interference impact does not exceed a threshold
level, such as, for example, a threshold noise temperature
increase. Accordingly, spectrum of another system/operator that,
for example, is interleaved with spectrum of a given
system/operator may be reused terrestrially and/or for space-based
communications by the given system/operator, provided that
interference is controlled. Relatively low power spectral density
communications may be provided by the given system/operator in the
spectrum of the other system/operator. Systems, methods, terminals,
satellites and/or satellite gateways may be provided according to
various embodiments of the invention.
[0045] The International Telecommunications Union (ITU) has
established an interference level of 6% noise temperature increase
(".DELTA.T/T") as a trigger to coordination between two or more
Mobile Satellite Systems (MSS). That is, in accordance with the ITU
rules, two MSS may interfere without requiring coordination
therebetween, provided that the mutual inter-system interference
from one system to the other does not exceed 6% .DELTA.T/T. A
satellite operator may, therefore, use spectrum allocated to
another satellite operator to communicate with space and/or
terrestrial components without coordination so long as the
interference generated by such communications does not exceed the
threshold specified by the ITU.
[0046] FIG. 1 is an illustration of first and second portions 100,
105 of spectrum that are allocated to and/or used by first and
second satellite operators for communications. Even though the
first and second portions 100, 105 of spectrum are illustrated in
FIG. 1 to be substantially contiguous, this need not be the case.
The portions 100a, 100b, and 100c of spectrum are allocated to
and/or used by the first satellite operator and the portions 105a
and 105b of spectrum are allocated to and/or used by the second
satellite operator. According to some embodiments of the invention,
the first satellite operator may provide a first family of
radioterminals that radiate a low power spectral density and may
allow at least one radioterminal of the first family of
radioterminals to communicate with a Space-Based Component (SBC) of
the first satellite operator using the low power spectral density
and at least one frequency within portions 105a and 105b that is
allocated to and/or used by the second satellite operator.
[0047] The low power spectral density communications are
illustrated by the horizontal lines in the portions 105a and 105b
of the spectrum in FIG. 1. These horizontal lines, illustrating a
level of interference, may be different for different frequency
segments. Accordingly, the horizontal line associated with
frequency segment 105a may, in accordance with some embodiments of
the invention, be at a level that is different to a level
associated with the horizontal line of frequency segment 105b. The
SBC of the first satellite operator may comprise at least one
satellite, which, in accordance with some embodiments of the
invention, may be at least one substantially geo-stationary
satellite.
[0048] The first satellite operator may also provide a second
family of radioterminals that may radiate a higher power spectral
density (compared to the first family of radioterminals) and the
first satellite operator may configure the second family of
radioterminals to communicate with the SBC using frequencies within
portions 100a-c allocated to and/or used by the first satellite
operator. The high power spectral density communications are
illustrated by the horizontal lines in the portions 100a-c of
spectrum in FIG. 1.
[0049] In other embodiments according to the invention, a
radioterminal of the first satellite operator may be configured to
operate in a first mode, wherein the radioterminal communicates
with an SBC of the first satellite operator using the low power
spectral density and at least one frequency within portions 105a-b
that is allocated to and/or used by the second satellite operator,
and a second mode in which the radioterminal may radiate a higher
power spectral density (compared to the first mode) when
communicating with the SBC using frequencies within portions 100a-c
allocated to and/or used by the first satellite operator.
[0050] The at least one radioterminal of the first family of
radioterminals (or the radioterminals operating in the first mode),
operating using the at least one frequency within the portions
105a-b allocated to and/or used by the second satellite operator,
may, in some embodiments according to the invention, be configured
to impact an SBC receiver of the second satellite operator by no
more than about (6-X) % .DELTA.T/T. As such, the first satellite
operator may allow an Ancillary Terrestrial Network (ATN)
comprising at least one Ancillary Terrestrial Component (ATC) to
communicate with ATN radioterminals over the at least one frequency
within the portions 105a-b that is allocated to and/or used by the
second satellite operator to the extent that the ATN and/or the
radioterminals thereof do not interfere with the satellite receiver
of the SBC of the second operator by more than, or substantially
more than, X % .DELTA.T/T. The aggregate (or total) SBC and ATN
communications of the first satellite operator, by the first
satellite operator, can thereby be controlled to interfere with the
satellite receiver of the SBC of the second satellite operator by
no more than, or substantially more than, 6% .DELTA.T/T.
[0051] In FIG. 1, the horizontal line across each portion of the
spectrum allocated to the second satellite operator denotes a power
spectral density value at an SBC of the second satellite operator
due to SBC and/or ATN communications of the first satellite
operator. Therefore, the aggregate radiated power spectral density
due to SBC and/or ATN communications of the first satellite
operator is, in accordance with some embodiments of the invention,
controlled and not allowed to exceed an interference level of more
than (or approximately more than) 6% .DELTA.T/T to an SBC of the
second satellite operator.
[0052] Accordingly, the first satellite operator may use (e.g.,
communicate using) at least some portions of spectrum of a band of
frequencies that are allocated to and/or used by the second
satellite operator and are not allocated to the first satellite
operator to thereby increase a spectrum contiguity measure of a
band of frequencies that may be used by the first satellite
operator to provide SBC and/or ATN communications using a band of
frequencies. It will be understood that, as used herein, the term
"communicate" or "communicating" includes actively/intentionally
transmitting and/or receiving using another provider's spectrum.
This is to be contrasted with incidental interference (i.e.,
Out-of-Band Emissions (OOBE)) that may inadvertently occur due to
the provider's communications using their own spectrum.
[0053] In some embodiments, it may be desirable, or mandated by FCC
regulations, that a MSS frequency not be used terrestrially if it
is not used for space-based communications. In some embodiments,
low data rate communications, for example, 100 bps communications,
at low power and/or power spectral density, may be
provided/assigned between the SBC and the first family of
radioterminals and/or the radioterminals in the first mode. In
another example, paging communications may be provided for/assigned
to the first family of radioterminals and/or for the first mode. In
other embodiments, high, medium and/or low data rate communications
may be provided by a first system/operator between a SBC of the
first system/operator and a family of radioterminals using
frequencies allocated to a second system/operator. Terrestrial
communications using frequencies that are allocated to and/or used
by the second system/operator may also take place at a high, medium
and/or low data rate such that the combined radiated power spectral
density of terrestrial and space-based communications of the first
system/operator, may be controlled to have an interference level at
an element of the second system/operator (such as, for example, a
SBC of the second system/operator) that is less than or
substantially equal to a predetermined threshold. In some
embodiments, the predetermined threshold is determined by the ITU
and/or is 6% .DELTA.T/T.
[0054] FIG. 2 is a schematic illustration of a cellular satellite
radiotelephone system of a first satellite operator that
communicates with space based and/or terrestrial components thereof
using spectrum allocated to a second satellite operator according
to some embodiments of the invention. As shown in FIG. 2, a
cellular satellite radiotelephone system 200 includes at least one
Space-Based Component (SBC) 211, such as a satellite, to
communicate with radiotelephones 220a-c served by the first
satellite operator. A cellular satellite radiotelephone system 205
includes at least one SBC 210, such as a satellite, to communicate
with radiotelephones 221 operated by a second satellite
operator.
[0055] In some embodiments according to the invention, the cellular
satellite radiotelephone systems 200, 205 are operated by different
satellite operators. Moreover, the cellular satellite
radiotelephone systems 200, 205 are separately licensed for
operation in the different frequency spectrums 100a-c and 105a-b
respectively as shown in FIG. 1.
[0056] Embodiments of satellite radiotelephone system 200 according
to the invention can include at least one gateway 260 that can
include an antenna 260a and an electronics system that can be
connected to other networks 262 including terrestrial and/or other
radiotelephone networks that may be configured to provide
circuit-switched and/or packet-switched services. The gateway 260
communicates with the SBC 211 over a satellite feeder link 212 and
may communicate with an Ancillary Terrestrial Network (ATN) 235
over a wireless and/or wireline communications link 242. The ATN
can include at least one Ancillary Terrestrial Component (ATC) 240,
which may include an antenna and an electronics system (not
shown).
[0057] Referring to the cellular satellite radiotelephone system
205, the SBC 210 can communicate with the radiotelephones 221 via
one or more respective satellite radiotelephone forward link
(downlink) frequencies f.sub.D2. The SBC 210 also receives
communications from the radiotelephones 221 over respective
satellite radiotelephone return link (uplink) frequencies f.sub.U2.
The frequencies f.sub.D2 and f.sub.U2 are included in the portions
105a-b of the spectrum that is allocated to the second satellite
operator as shown in FIG. 1. The cellular satellite radiotelephone
system 205 can include other components not shown.
[0058] Referring to the cellular satellite radiotelephone system
200, the SBC 211 is configured to transmit wireless communications
to a plurality of radiotelephones 220a-c in a satellite footprint.
In particular, the SBC 211 is configured to transmit communications
to the radiotelephones 220a using a downlink frequency f.sub.D1.
The SBC 211 is also configured to receive wireless communications
from the radiotelephones 220a over a satellite uplink frequency
f.sub.U1. The radiotelephones 220a are configured to communicate
with the ATC 240 over downlink frequency f'.sub.D1 and satellite
uplink frequency f'.sub.U1. The frequencies f.sub.D1, f.sub.U1,
f'.sub.D1, and f'.sub.U1, are included in the portions 100a-c of
the spectrum that are allocated to the first satellite operator as
shown in FIG. 1. It will be understood that the other
radiotelephones 220b-c may also communicate (or be selectively
configured to communicate) with the SBC 211 using the frequencies
f.sub.D1 and f.sub.U1 and f'.sub.D1 and f'.sub.U1. It will be
understood that each of the radiotelephones 220a-c can represent a
family of radiotelephones as described herein.
[0059] Radiotelephones 220b can communicate with the ATC 240 over
the uplink frequency f.sub.U1 and downlink frequency f.sub.D1.
Thus, as illustrated in FIG. 2, radiotelephone 220a may be
communicating with the SBC 211 while radiotelephone 220b may be
communicating with the ATC 240. In some embodiments according to
the invention, the radiotelephone 220b can also communicate with
the SBC 211 using uplink and downlink frequencies allocated to the
first satellite operator.
[0060] As further shown in FIG. 2, in some embodiments according to
the invention, radiotelephones 220c can communicate with the SBC
211 over the downlink/uplink frequencies f.sub.D2 and f.sub.U2 that
are included in the portions 105a-b of the spectrum allocated to
the second satellite operator in FIG. 1. The radiotelephones 220c
can also communicate with the ATC 240 using the frequencies
f''.sub.D2 and f''.sub.U2 that are included in the portions 105a-b
of the spectrum allocated to the second satellite operator.
[0061] It will be understood that in some embodiments according to
the invention, the radiotelephones 220c can be configured to
communicate with the SBC 211 using the frequencies f'.sub.D2 and
f'.sub.U2, without communicating with the ATC 240 using the
frequencies f''.sub.D2 and f''.sub.U2 (or to use frequencies other
than f''.sub.D2 and f''.sub.U2). In other embodiments according to
the invention, the radiotelephones 220c can be configured to
communicate with the ATC 240 using the frequencies f''.sub.D2 and
f''.sub.U2 and configured not to communicate with the SBC 211 using
the frequencies f'.sub.D2 and f'.sub.U2 (or to use frequencies
other than f'.sub.D2 and f'.sub.U2.)
[0062] The cellular satellite radiotelephone system 200 may also
include an aggregate radiated power spectral density controller
(i.e., an aggregate interference controller) which may be included
in ATN 235, gateway 260, SBC 211 and/or be distributed between ATN
235 gateway 260 and SBC 211 or be a stand-alone system element. The
aggregate radiated power spectral density controller may be
configured to manage the operations of the ATC 240 and/or the
radioterminals 220a-c to control the aggregate radiated Power
Spectral Density (PSD) generated by the system 200, which may
interfere with the operation of the system 205. In particular, the
aggregate radiated power spectral density controller can manage,
for example, a number of users and/or electro-magnetic emissions
thereof operating in the satellite footprint shown in FIG. 2 to
maintain an aggregate radiated power spectral density of the system
200 below a specified threshold. Accordingly, the aggregate
radiated power spectral density controller may be configured to
control the operation of radioterminals 220a-c using uplink and/or
downlink frequencies allocated to the first and/or second satellite
operator.
[0063] As shown in FIG. 2, the radioterminals 220a and 220b using
the uplink and downlink frequencies (allocated to the first
satellite operator) to communicate with the ATC 240 can generate an
out-of-band terrestrial power spectral density interference
component (PSD.sub.OOBT) at the SBC 210. Furthermore, communication
between the SBC 211 and the radioterminals 220a using the
frequencies allocated to the first satellite operator can also
generate an out-of-band space-based PSD interference component
(PSD.sub.OOSSB) at the SBC 210. Accordingly, the aggregate radiated
power spectral density controller can manage the operation of the
radioterminals 220a-b to maintain the out of band terrestrial
and/or space based PSD interference components at the SBC 210 at or
below a desired level.
[0064] The aggregate radiated power spectral density controller
("the controller") can manage the interference at the SBC 210
generated by the components of the system 200 by, for example,
adjusting the number of radioterminals that operate in the
footprint shown in FIG. 2. For example, in a CDMA system, the
controller may reduce a number of codes available for use by
radioterminals over a geographic area. Alternatively or in
combination with the above, the controller may adjust a data rate
provided by at least some radioterminals over a geographic area, or
may configure a number of the radioterminals to operate using a
different (e.g., lower) vocoder rate. The adjusted parameter(s) can
allow the aggregate PSD reaching SBC 210 to be, for example,
reduced so that the aggregate PSD at SBC 210 is maintained at an
interference level that is less than, or approximately equal to,
for example, 6% .DELTA.T/T. In systems using other types of
air-interfaces, the controller may, instead of or in addition to
the above, adjust other parameters. For example, in a GSM system,
the controller may change a number of time slots that at least some
radiotelephones may use to transmit/receive to manage the PSD at
the SBC 210.
[0065] Techniques used to maintain aggregate radiated power
spectral density at levels equal to or less than a threshold are
described in greater detail in, for example, U.S. patent
application Ser. No. 11/300,868, entitled Aggregate Radiated Power
Control for Multi-Band/Multi-Mode Satellite Radiotelephone
Communications Systems and Methods, filed Dec. 15, 2005, the
entirety of which is incorporated herein by reference.
[0066] In addition to managing the out-of-band interference
components generated by communications using uplink/downlink
frequencies allocated to a first satellite operator, the aggregate
radiated power spectral density controller also maintains control
over in-band interference components generated by the use of the
spectrum allocated to the second satellite operator. In particular,
the use of uplink and downlink frequencies allocated to the second
satellite operator by the radiotelephones 220c can generate in-band
terrestrial and space based PSD interference components
(PSD.sub.IBT and PSD.sub.IBSB) at the SBC 210. For example, use of
the uplink and/or downlink frequencies, f'.sub.U2 and f'.sub.D2,
can generate an in-band space based PSD interference component at
the SBC 210. Similarly, use of the uplink and/or downlink
frequencies f''.sub.U2 and f''.sub.D2 can generate an in-band
terrestrial PSD interference component at the SBC 210.
[0067] Accordingly, the aggregate radiated power spectral density
controller also manages the configuration and operation of the
radioterminals 220c. Thus, the controller maintains a desired
aggregate radiated power spectral density including the
interference components generated by the use of the spectrum
allocated to the first satellite provider as well as the
interference components generated by the use of the spectrum
allocated to the second satellite operator. In particular, the
aggregate radiated power spectral density controller can combine
the interference components generated by the in-band terrestrial
and space-based PSD with the out-of-band terrestrial and
space-based PSD interference components to provide a desired
overall aggregate radiated power spectral density at the SBC
210.
[0068] To manage the overall aggregate radiated power spectral
density at the SBC 210, the controller may configure a number of
the radioterminals 220c to communicate using the spectrum allocated
to the first satellite operator. To reduce the in-band terrestrial
and space-based PSD interference components, the controller can
adjust the parameters used by the radiotelephones 220c to
communicate with the SBC 211 and the ATC 240. For example, in some
embodiments, the controller can reduce a number of users configured
to communicate using the spectrum allocated to the second satellite
operator. In other embodiments according to the invention, the
controller can configure the radioterminals 220c and/or the SBC 211
for low data rate service, such as paging services associated with
the radioterminals 220c. In still other embodiments according to
the invention, the controller can configure the radioterminals 220c
to use relatively low rate vocoders, such as 4 kbps (vs. 16
kbps).
[0069] It will be understood that in any of these approaches
according to embodiments of the invention, the aggregate radiated
power spectral density controller can affect the in-band
terrestrial and space-based PSD interference components so that the
PSD at the SBC 210 does not exceed a predetermined threshold for
interference.
[0070] As described above, using at least a portion of the spectrum
allocated to the second satellite operator, along with the spectrum
allocated to the first satellite operator, can provide a continuous
band of spectrum for communications by the first satellite
operator. In some embodiments according to the invention, the
controller can configure a number of the radioterminals 220c to
operate using a portion of the spectrum allocated to the second
satellite provider (i.e., the second system 205) for communications
with the ATC 240. The controller can further configure the
radioterminals 220c to communicate with the SBC 211 also using a
portion of the spectrum allocated to the second satellite operator
to provide relatively low data rate communications thereto/from the
SBC 211.
[0071] This approach may allow a greater number of radioterminals
220c to operate using the spectrum allocated to the second
satellite operator as the in-band interference generated by
communicating with the ATC 240 may be low compared to interference
generated by communicating with the SBC 211 using the spectrum
allocated to the second satellite provider. Accordingly, the
aggregate radiated power spectral density controller may provide a
net benefit (for example in terms of increased number of
radioterminals 220c that can be serviced) while still maintaining
the aggregate radiated PSD at the SBC 210 at or below a specified
threshold for interference. This may be accomplished even though
the aggregate radiated power spectral density controller may, in
some embodiments according to the invention, configure the
radioterminals 220a and 220b to reduce the interference components
generated by the out-of-band operation of those radioterminals.
Therefore, at least some of the spectrum allocated to the second
satellite operator may be used by the first satellite operator,
while still maintaining an interference at or below a specified
threshold, by preferentially configuring the radioterminals 220c to
use at least a portion of the spectrum of the second satellite
operator to communicate with the ATC 240 rather than the SBC
211.
[0072] FIG. 3 is a block diagram of radiotelephones that may be
used to communicate with space-based components and/or Ancillary
Terrestrial Components using spectrum allocated to another
satellite operator at an aggregate radiated power spectral density
that is less than a predetermined threshold. In some embodiments
according to the invention, a radiotelephone 320 can be used with
satellite radiotelephone systems according to some embodiments of
the present invention that include an ancillary terrestrial
component and a space-based component that use substantially the
same band and substantially the same air interface. The ability to
use spectrum allocated to another satellite provider can, for
example, increase spectrum contiguity and/or a number users that
can be supported.
[0073] Referring to FIG. 3, a single Radio Frequency (RF) chain
including low pass filters 322, up and down converters 324a, 324b,
Local Oscillators (LO) 326, Low Noise Amplifier (LNA) 328, Power
Amplifier (PA) 332, band-pass filters 334 and antenna 336, may be
used. A single baseband processor 342 may be used, including an
analog-to-digital converter (A/D) 344, a digital-to-analog
converter (D/A) 346 and a Man-Machine Interface (MMI) 348. An
optional Bluetooth interface 352 may be provided. An
Application-Specific Integrated Circuit (ASIC) 354 may include
thereon Random Access Memory (RAM) 356, Read-Only Memory (ROM) 358,
a microprocessor (.mu.P) 362, logic for ancillary terrestrial
communications (ATC Logic) 364 and logic for space-based
communications (Space Segment Logic or SS Logic) 366. The SS Logic
366 can be used to accommodate satellite-unique requirements over
and above those of cellular, ATC or PCS, such as a satellite-unique
vocoder, a satellite forward error correction coding scheme, a
satellite-unique interlever, etc. However, in accordance with some
embodiments of the invention, this added gate count may not
substantially increase the cost of the ASIC 354.
[0074] As described herein, some embodiments of the present
invention may arise from a recognition that spectrum belonging to
another satellite operator may be reused by a given operator,
provided that an intersystem interference level does not exceed a
given threshold, such as, for example, a given noise temperature
increase (i.e., .DELTA.T/T). Accordingly, spectrum of another
operator that, for example, is interleaved with spectrum of a given
operator may be reused terrestrially and/or for space-based
communications by the given operator, provided that the intersystem
interference level is controlled to not exceed the given threshold.
Accordingly, low power spectral density communications, relative to
an acceptable intersystem interference level of a space segment of
the other operator, may thus be provided by the given operator in
at least a portion of the spectrum of the other operator.
[0075] According to some embodiments of the invention, the given
operator may be Mobile Satellite Ventures, LP ("MSV") and the other
operator may be Inmarsat, Globalstar, Iridium, XM-Satellite Radio,
Sirius Satellite Radio, TerreStar and/or ICO. It will be
appreciated by those skilled in the art that although the
principles, systems and/or methods described herein have been
described in the context of specific illustrative embodiments
relating to first and second satellite systems/operators, the
principles, systems and/or methods of the present invention may be
applied to any first and second systems. For example, in some
embodiments according to the invention, the first system/operator
may be a satellite system/operator and the second system/operator
may be a cellular/PCS system/operator. In other embodiments, the
first system/operator may be a cellular/PCS system/operator and the
second system/operator may be a cellular/PCS system/operator,
etc.
[0076] In the specification, there have been disclosed embodiments
of the invention and, although specific terms are employed, they
are used in a generic and descriptive sense only and not for
purposes of limitation, the scope of the invention being set forth
in the following claims.
* * * * *