|
Mobile Phone Patent Abstract
A system includes antenna control stations and a system interface.
Each antenna control stations directs an orientation of an associated
antenna to search for an identification signal associated with a
mobile phone. The antenna control station communicates a detection
response describing the orientation of the associated antenna. The
system interface computes the location of the mobile phone based
on the detection responses received from the antenna control stations.
Mobile Phone Patent Claims
What is claimed is:
1. A method for determining the location of a mobile phone, comprising:
receiving a location request from a mobile communication system,
the location request including an identification signal associated
with a mobile phone and an approximate location of the mobile phone;
receiving one or more detection responses, each detection response
including an orientation at which a directional antenna detects
the identification signal; determining a location of the mobile
phone independent of the mobile communication system based on the
detection responses; identifying one or more directional antennas
from a plurality of directional antennas; calculating an initial
orientation for each of the identified directional antennas based
on the approximate location of the mobile phone; and communicating
to each of the identified directional antennas the initial orientation
calculated for that particular identified directional antenna.
2. The method of claim 1, wherein the detection response comprises
an angular azimuth.
3. The method of claim 1, wherein: one or more directional antennas
comprises three directional antennas; and determining a location
comprises triangulating the location based on the location of each
of the directional antennas and the orientation of each of the directional
antennas.
4. The method of claim 1, wherein the location request identifies
one of a plurality of mobile communication networks, and further
comprising: generating a location response including the location
of the mobile phone; and communicating the location response to
the identified mobile communication network.
5. The method of claim 4, wherein the location response comprises
a latitude and a longitude associated with the mobile phone.
6. The method of claim 4, wherein the location response comprises
directions for driving from a predetermined location to the location
of the mobile phone.
7. A method for determining the location of a mobile phone, comprising:
receiving a detection request identifying an identification signal
associated with a mobile phone, the detection request comprising
an initial orientation for a directional antenna; setting an orientation
of the directional antenna based on the initial orientation; directing
the directional antenna to detect the identification signal; determining
an orientation of the directional antenna when the identification
signal is detected; and communicating the orientation to a remote
location for determining the location of the mobile phone.
8. The method of claim 7, wherein communicating the orientation
comprises communicating an angular azimuth.
9. The method of claim 7, wherein directing a directional antenna
comprises mechanically steering the directional antenna.
10. The method of claim 7, wherein directing a directional antenna
comprises electronically steering the directional antenna.
11. A system for locating a mobile phone, comprising: a plurality
of antenna control stations, each antenna control station associated
with an antenna and each antenna control station operable to: direct
an orientation of the associated antenna; determine whether the
associated antenna detects an identification signal associated with
a mobile phone at the present orientation of the associated antenna;
and communicate a detection response describing the orientation
of the associated antenna when the associated antenna detects the
identification signal; and a system interface, operable to: compute
the location of the mobile phone based on the detection responses
received from the antenna control stations; receive an approximate
location of the mobile phone; identify a number of antennas from
a plurality of antennas based on the approximate location; calculate
an initial orientation for each of the identified antennas based
on the approximate location; and communicate the initial orientation
for each of the identified antennas to the antenna control station
associated with the particular identified antenna to be used to
determine a starting orientation for the particular identified antenna.
12. The system of claim 11, wherein the detection response comprises
an angular azimuth at which the associated antenna is able to detect
the identification signal.
13. The system of claim 11, wherein the system interface is operable
to: receive location requests identifying an identification signal
associated with the mobile phone from a plurality of mobile communication
systems; identify the mobile communication system that sent a particular
location request; and communicate the location of the mobile phone
to the identified mobile communication system.
14. The system of claim 11, wherein computing the location comprises
computing a latitude and a longitude.
15. The system of claim 11, wherein computing the location comprises
generating directions for driving from a predetermined location
to the location of the mobile phone.
16. The system of claim 11, wherein adjusting an orientation of
the associated antenna comprises mechanically steering the associated
antenna.
17. The system of claim 11, wherein adjusting an orientation of
the associated antenna comprises electronically steering the associated
antenna.
18. An apparatus for determining the location of a mobile phone,
the apparatus comprising: a system interface operable to: receive
a location request including an identification signal associated
with a mobile phone and an approximate location of the mobile phone;
receive one or more detection responses, each detection response
including an orientation at which a directional antenna detects
the identification signal; and determine a location of the mobile
phone based on the detection responses; identify one or more directional
antennas from a plurality of directional antennas; calculate an
initial orientation for each of the identified directional antennas
based on the approximate location of the mobile phone; and communicate
to each of the identified directional antennas the initial orientation
calculated for that particular identified directional antenna.
19. The apparatus of claim 18, wherein the detection response comprises
an angular azimuth.
20. The apparatus of claim 18, wherein: one or more directional
antennas comprises three directional antennas; and determining a
location comprises triangulating the location based on the location
of each of the directional antennas and the orientation of each
of the directional antennas.
21. The apparatus of claim 18, wherein the location request identifies
one of a plurality of mobile communication networks, and the system
interface is further operable to: generate a location response the
location of the mobile phone; and communicate the location response
to the identified mobile communication network.
22. The apparatus of claim 18, wherein the location response comprises
a latitude and a longitude associated with the mobile phone.
23. The apparatus of claim 18, wherein the location response comprises
directions for driving from a predetermined location to the location
of the mobile phone.
24. An apparatus for determining the location of a mobile phone,
comprising: an antenna control station operable to: receive a detection
request identifying an identification signal associated with a mobile
phone and comprising an initial orientation for a directional antenna;
set an orientation of the directional antenna based on the initial
orientation; direct the directional antenna to detect the identification
signal; determine an orientation of the directional antenna when
the identification signal is detected; and communicate the orientation
to a system interface to be used in determining the location of
the mobile phone.
25. The apparatus of claim 24, wherein the orientation comprises
an angular azimuth.
26. The apparatus of claim 24, wherein directing a directional
antenna comprises mechanically steering the directional antenna.
27. The apparatus of claim 24, wherein directing a directional
antenna comprises electronically steering the directional antenna.
28. A method for determining the location of a mobile phone, comprising:
receiving a location request comprising an identification signal
associated with a mobile phone and an approximate location of the
mobile phone; identifying one or more directional antennas from
a plurality of directional antennas; calculating an initial orientation
for each of the identified directional antennas based on the approximate
location of the mobile phone; communicating to each of the identified
directional antennas the initial orientation calculated for that
particular identified directional antenna; receiving one or more
detection responses from one or more of the identified directional
antennas, each detection response including an orientation at which
a directional antenna detects the identification signal; and determining
a location of the mobile phone based on the detection responses.
29. The method of claim 28, wherein the orientation comprises an
angular azimuth.
30. The method of claim 28, wherein: one or more directional antennas
comprises three directional antennas; and determining a location
comprises triangulating the location based on the location of each
of the directional antennas and the orientation of each of the directional
antennas.
31. The method of claim 28, wherein the location request identifies
one of a plurality of mobile communication networks, and further
comprising: generating a location response including the location
of the mobile phone; and communicating the location response to
the identified mobile communication network.
32. The method of claim 28, wherein the location response comprises
a latitude and a longitude associated with the mobile phone.
33. The method of claim 28, wherein the location response comprises
directions for driving from a predetermined location to the location
of the mobile phone.
34. A computer program stored on a computer readable medium, the
computer program operable to: receive a location request from a
mobile communication system, the location request including an identification
signal associated with a mobile phone and an approximate location
of the mobile phone; receive one or more detection responses, each
detection response including an orientation at which a directional
antenna detects the identification signal; determine a location
of the mobile phone independent of the mobile communication system
based on the detection responses; identify one or more directional
antennas from a plurality of directional antennas; calculate an
initial orientation for each of the identified directional antennas
based on the approximate location of the mobile phone; and communicate
to each of the identified directional antennas the initial orientation
calculated for that particular identified directional antenna.
35. The computer program of claim 34, wherein the orientation comprises
an angular azimuth.
36. The computer program of claim 34, the computer program further
operable to receive one or more detection responses by receiving
three directional responses and to determine a location by triangulating
the location based on the location of each of the directional antennas
and the orientation of each of the directional antennas.
37. The computer program of claim 34, wherein the location request
identifies one of a plurality of mobile communication networks,
and further wherein the computer program is further operable to:
generate a location response including the location of the mobile
phone; and communicate the location response to the identified mobile
communication network.
38. The computer program of claim 34, wherein the computer program
is further operable to generate a location response by generating
the location response comprising a latitude and a longitude associated
with the mobile phone.
39. The computer program of claim 34, wherein the computer program
is further operable to generate a location response by generating
the location response comprising directions for driving from a predetermined
location to the location of the mobile phone.
40. A computer program for determining the location of a mobile
phone, the computer program operable to: receive a detection request
identifying an identification signal associated with a mobile phone,
the detection request comprising an initial orientation for a directional
antenna; set an orientation of the directional antenna based on
the initial orientation, direct the directional antenna to detect
the identification signal; determine an orientation of the directional
antenna when the identification signal is detected; and communicate
the orientation to a remote location for determining the location
of the mobile phone.
41. The computer program of claim 40, wherein the computer program
is further operable to communicate the orientation by communicating
an angular azimuth.
42. The computer program of claim 40, wherein the computer program
is further operable to direct a directional antenna by mechanically
steering the directional antenna.
43. The computer program of claim 40, wherein the computer program
is further operable to direct a directional antenna by electronically
steering the directional antenna.
44. A computer program for determining the location of a mobile
phone, the computer program operable to: receive a location request
comprising an identification signal associated with a mobile phone
and an approximate location of the mobile phone; identify one or
more directional antennas from a plurality of directional antennas;
calculate an initial orientation for each of the identified directional
antennas based on the approximate location of the mobile phone;
communicate to each of the identified directional antennas the initial
orientation calculated for that particular identified directional
antenna; receive one or more detection responses from one or more
of the identified directional antennas, each detection response
including an orientation at which a directional antenna detects
the identification signal; and determine a location of the mobile
phone based on the detection responses.
45. The computer program of claim 44, wherein the orientation comprises
an angular azimuth.
46. The computer program of claim 44, wherein the computer program
is further operable to receive one or more detection responses by
receiving three directional responses and to determine a location
by triangulating the location based on the location of each of the
directional antennas and the orientation of each of the directional
antennas.
47. The computer program of claim 44, the computer program further
operable to receive the location request by receiving a location
request identifying one of a plurality of mobile communication networks,
and the computer program further operable to: generate a location
response comprising the location of the mobile phone; and communicate
the location response to the identified mobile communication network.
48. The computer program of claim 47, the computer program operable
to generate the location response by generating a location response
comprising a latitude and a longitude associated with the mobile
phone.
49. The computer program of claim 47, the computer program operable
to generate the location response by generating a location response
comprising directions for driving from a predetermined location
to the location of the mobile phone.
50. A system for determining the location of a mobile phone, comprising:
means for receiving a location request from a mobile communication
system, the location request including an identification signal
associated with a mobile phone and an approximate location of the
mobile phone; means for receiving one or more detection responses,
each detection response including an orientation at which a directional
antenna detects the identification signal; means for determining
a location of the mobile phone independent of the mobile communication
system based on the detection responses; means for identifying one
or more directional antennas from a plurality of directional antennas;
means for calculating an initial orientation for each of the identified
directional antennas based on the approximate location of the mobile
phone; and means for communicating to each of the identified directional
antennas the initial orientation calculated for that particular
identified directional antenna.
51. A system for determining the location of a mobile phone, comprising:
means for receiving a detection request identifying an identification
signal associated with a mobile phone, the detection request comprising
an initial orientation for a directional antenna; means for setting
an orientation of the directional antenna based on the initial orientation;
means for directing the directional antenna to detect the identification
signal; means for determining an orientation of the directional
antenna when the identification signal is detected; and means for
communicating the orientation to a remote location for determining
the location of the mobile phone.
52. A system for determining the location of a mobile phone, comprising:
means for receiving a location request comprising an identification
signal associated with a mobile phone and an approximate location
of the mobile phone; means for identifying one or more directional
antennas from a plurality of directional antennas; means for calculating
an initial orientation for each of the identified directional antennas
based on the approximate location of the mobile phone; means for
communicating to each of the identified directional antennas the
initial orientation calculated for that particular identified directional
antenna; means for receiving one or more detection responses from
one or more of the identified directional antennas, each detection
response including an orientation at which a directional antenna
detects the identification signal; and means for determining a location
of the mobile phone based on the detection responses.
Mobile Phone Patent Description
TECHNICAL FIELD OF THE INVENTION
This invention relates in general to mobile phones, and more particularly
to locating mobile phones.
BACKGROUND OF THE INVENTION
Mobile phone use has increased rapidly over the past decade. Mobile
phones offer not only convenience but also significant safety benefits
by providing stranded motorists, pedestrians, and other individuals
separated from conventional landline phones with the ability to
contact emergency service providers if needed.
However, unlike conventional landline phones, mobile phones do
not provide emergency service providers with information indicating
where the caller is located. This is often critical for emergency
providers as the caller may become incapacitated during the call,
disconnected, or otherwise prevented from supplying the emergency
service provider with this information. The need for this information
is only amplified in the case of mobile phones as the mobile caller
may not actually know his or her whereabouts. Consequently, emergency
service providers may be unable to assist the mobile caller.
Some solutions to this problem have been attempted utilizing the
Global Positioning System (GPS), a network of satellites capable
of locating objects on the surface of the earth. However, GPS solutions
are undesirable for a number of reasons. A primary drawback is the
fact that GPS solutions require an unimpeded line-of-sight between
a GPS satellite and the mobile phone. Thus, a GPS-based system will
be unable to locate a mobile phone user calling from within a building.
Therefore, a system is desired that is capable of determining the
location of a caller communicating with an emergency service provider
using a mobile phone.
SUMMARY OF THE INVENTION
From the foregoing, it may be appreciated by those skilled in the
art that a need has arisen for a method of locating a caller using
a mobile phone. In accordance with the present invention, the disadvantages
and problems associated mobile phones have been substantially reduced
or eliminated. In particular, the present invention provides a system
and method for locating a mobile phone using directional antennas.
In accordance with one embodiment of the present invention, a method
for determining the location of a mobile phone comprises receiving
a location request including an identification signal associated
with a mobile phone, receiving one or more detection responses,
each detection response including an orientation at which a directional
antenna detects the identification signal; and determining a location
of the mobile phone based on the detection responses.
In accordance with another embodiment of the present invention,
a system for locating a mobile phone, comprises a plurality of antenna
control stations, each antenna control station associated with an
antenna and each antenna control station operable to adjust an orientation
of the associated antenna, to determine whether the associated antenna
detects an identification signal associated with a mobile phone
at the present orientation of the associated antenna, and to communicate
a detection response describing the orientation of the associated
antenna when the associated antenna detects the identification signal;
and a system interface operable to compute the location of the mobile
phone based on the detection responses received from the antenna
control stations.
Important technical advantages of certain embodiments of the present
invention include determining the location of a caller independent
of the communication system on which the caller is communicating.
Other important technical advantages of certain embodiments of the
present invention include the ability to locate a caller absent
a clear line-of-site path to the caller, the ability to locate callers
on multiple communication systems, and the ability to locate callers
with increased precision.
Other technical advantages of the present invention will be readily
apparent to one skilled in the art from the following figures, descriptions,
and claims. Moreover, while specific advantages have been enumerated
above, various embodiments may include all, some, or none of the
enumerated advantages.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and
its advantages, reference is now made to the following description,
taken in conjunction with the accompanying drawings, in which:
FIG. 1 illustrates a mobile communication system, a caller, and
a location system according to one embodiment of the present invention;
FIG. 2 is a block diagram illustrating the contents and operation
of the location system;
FIG. 3 is a block diagram illustrating the contents and operation
of an antenna station;
FIG. 4A illustrates a location request according to one embodiment
of the present invention;
FIG. 4B illustrates a location response according to one embodiment
of the present invention;
FIG. 5A illustrates a detection request according to one embodiment
of the present invention;
FIG. 5B illustrates a detection response according to one embodiment
of the present invention;
FIG. 6 is a flow chart illustrating the operation of a system interface
in accordance with one embodiment of the present invention; and
FIG. 7 is a flow chart illustrating the operation of an antenna
control station in accordance with one embodiment of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a system 100. System 100 includes a mobile communication
system 110, a location system 120, and an emergency service provider
130 coupled together by a network 140. FIG. 1 also includes antennas
112, cell towers 122 and a mobile phone 150. Location system 120
uses directional antennas 112 to determine the location of mobile
phone 150 receiving communication service from mobile communication
system 110.
Mobile phone 150 is a mobile communication device being used by
a caller attempting to contact emergency service provider 130 through
mobile communication system 110. Examples of mobile phone 150 include
cellular phones, personal digital assistants ("PDAs"),
laptop computers and any other portable devices which may be used
to contact emergency service provider 130 through mobile communication
system 110.
Mobile communication system 110 provides conventional mobile communication
service to mobile phone 150. If mobile communication system 110
receives a communication signal from mobile phone 150 requesting
emergency service, mobile communication system 110 communicates
information identifying the mobile phone 150 to location system
120 in the form of a location request 160. Mobile communication
system 110 may include any combination of hardware and/or software
suitable to implement the functionality as described. Although system
100 includes a single mobile communication system 110, particular
embodiments of system 100 may contain any number of mobile communication
systems 110 in communication with location system 120.
Location system 120 locates an identification signal associated
with mobile phone 150 and communicates the location to emergency
service provider 130 or mobile communication system 110 in the form
of a location response 162. Location system 120 may include any
suitable combination of hardware and/or software suitable to implement
the functionality as described.
Location system 120 may be independent from mobile communication
system 110. Examples of independence may include: the ability of
location system 120 to communicate with a particular mobile communication
system 110 without regard for the protocols used internally by the
mobile communication system 110; the ability of location system
120 to communicate with multiple mobile communication systems 110;
the ability of location system 120 to itself determine the location
of particular antennas 112; the fact that location system 120 does
not include any of the components of mobile communication system
110; or any other suitable form of operational or physical independence.
Moreover, the independence of location system 120 contemplates passive
operation in which no changes need be made to the wireless infrastructure
of mobile communication system 110.
Emergency service provider 130 is a person, group of people, or
entity responsible for providing services to a caller using mobile
phone 150. Emergency service provider 130 may represent a police
or fire department, a roadside-assistance service provider, a wilderness
rescue unit or the provider of any other services which may require
the service provider to determine the location of a caller using
mobile phone 150. Although system 100 includes a single emergency
service provider 130, particular embodiments of system 100 may contain
any number of emergency service providers 130.
Network 140 may represent any hardware and/or software configured
to communicate information in the form of packets, cells, frames,
segments or other portions of data. Network 140 may include routers,
hubs, switches, gateways, or any other suitable component to any
suitable form or arrangement. In general, network 140 may comprise
any combination of public or private communication equipment such
as elements of a public switched telephone network (PSTN), a global
computer network such as the internet, a local area network (LAN),
a wide-area network (WAN), or other appropriate communication equipment.
Network 140 may represent a single network or any combination of
separate networks independently connecting mobile communication
system 110, location system 120, and emergency service provider
130.
Cell towers 122 represent conventional mobile communication towers
for receiving mobile communication from mobile phone 150. Each cell
tower 122 is capable of receiving calls from a limited, adjacent
area that is divided into a plurality of cell sectors 124. Cell
tower 122 receives mobile communication signals from mobile phone
150 and communicates the mobile communication signals to mobile
communication system 110. Cell towers 122 may implement any form
of wireless communication technology or protocols, including TDMA,
FDMA, CDMA, GSM or any other suitable analog or digital communication
technique in any single or combination of frequency bands.
Antennas 112 are narrow-beam, directional antennas capable of detecting
mobile communication signals at the frequencies used by mobile communication
system 110. Location system 120 manipulates antenna 112 to search
for mobile phone 150. Each antenna 112 detects mobile communication
signals from mobile phones located substantially in front of antenna
112 based on the current orientation of antenna 112. Location system
120 may steer antennas 112 mechanically. In a particular embodiment,
location system 120 may steer antennas 112 using any suitable combination
of motors, controllers, and control software. Location system 120
may also include electronically steered antennas 112 that incorporate
beam forming networks, sectored elements, radiofrequency components,
and/or signal processing software to resolve an angular direction
to mobile phone 150.
In operation, a cell tower 122 receives a mobile communication
signal from mobile phone 150 requesting service from emergency service
provider 130. Mobile phone 150 is located in a particular cell sector
124 associated with the particular cell tower 122. Cell tower 122
transmits the mobile communication signal to mobile communication
system 110.
Based on information contained in the mobile communication signal,
mobile communication system 110 generates location request 160 which
includes an identification signal 152 identifying the mobile phone
150 to be located. Identification signal 152 may carry a mobile
identification number (MIN), electronic serial number (ESN), or
any other information uniquely associated with mobile phone 150.
Location request 160 also may include information identifying the
channel on which mobile phone 150 is communicating and other information
describing the type of mobile phone 150, the manner in which mobile
phone 150 is communicating, or any other information useful for
locating mobile phone 150. Moreover, the contents and format of
location request 160 in a particular embodiment of system 100 may
vary depending on the particular mobile communication system 110
and cell tower 122 communicating with mobile phone 150.
Additionally, location request 160 may include information describing
an approximate location of mobile phone 150 and, if system 100 includes
more than one mobile communication system 110, information identifying
the mobile communication system 110 making the request. Mobile communication
system 110 communicates location request 160 to location system
120 through network 140.
Using information provided in location request 160, location system
120 identifies one or more antennas 112 to search for identification
signal 152 associated with mobile phone 150. In a particular embodiment
of system 100, location system 120 calculates an approximate location
of mobile phone 150 based on information included in location request
160. Identified antennas 112 then use the approximate location as
a starting point for their search.
Location system 120 manipulates the identified antennas 112, mechanically
or electronically, to detect identification signal 152. Location
system 120 then determines the location of mobile phone 150 based
on the location and orientation of each identified antenna 112 that
detects identification signal 152.
After determining the location of mobile phone 150, location system
120 generates location response 162 which includes information describing
the location of mobile phone 150. In a particular embodiment of
system 100, location system 120 communicates location response 162
to emergency service provider 130 through network 140. Alternatively,
location system 120 may communicate location response 162 to mobile
communication system 110 through network 140. Mobile communication
system 110 is then responsible for communicating the location of
mobile phone 150 to emergency service provider 130.
FIG. 2 is a block diagram illustrating the contents and operation
of location system 120 according to a particular embodiment of system
100. Location system 120 includes system interface 210, multiple
antenna control stations 220, and network 230. Network 230 connects
system interface 210 to antenna control stations 220.
System interface 210 facilitates communication between location
system 120 and mobile communication system 110. System interface
210 also identifies antennas 112 for location system 120 to use
in searching for mobile phone 150 and processes the results of the
search to determine the location of mobile phone 150.
System interface 210 may include a memory 212 and a processor 214.
Memory 212 may hold the locations of antennas 112, locations of
cell sectors 124, channel descriptions, phone numbers for emergency
service providers 130, or any other information pertaining to the
components of system 100 or mobile phone 150. Additionally, memory
212 may hold code to be executed by processor 214. Memory 212 may
include any collection and arrangement of volatile or non-volatile,
local or remote devices suitable for storing data, such as for example
random access memory (RAM) devices, read only memory (ROM) devices,
magnetic storage devices, optical storage devices, or any other
suitable data storage devices.
Processor 214 identifies antennas 112, computes the location of
mobile phone 150 and provides other computational functionality
that may be used by system interface 210. Processor 214 may be a
general purpose computer, dedicated microprocessor, or any other
suitable processing device. Examples of processor 214 include application-specific
integrated circuits (ASICs), field-programmable gate arrays (FPGAs),
digital signal processors (DSPs) and any other suitable specific
or general purpose processors.
Antenna control stations 220 manipulate antennas 112 to detect
identification signal 152. Each antenna control station 220 then
communicates information describing the bearing at which the antenna
112 associated with the particular antenna control station 220 detected
identification signal 152. Antenna control stations 220 may be either
physically distinct from or integrated with system interface 210
and may include any combination of hardware and/or software as need
to implement the functionality as described. Additionally, the antenna
control stations 220 associated with multiple antennas 112 may be
integrated into a single physical component.
Network 230 may represent any hardware and/or software configured
to communicate information in the form of packets, cells, frames,
segments or other portions of data. Network 230 may include routers,
hubs, switches, gateways, or any other suitable component to any
suitable form or arrangement. In general, network 230 may comprise
any combination of public or private communication equipment such
as elements of a public switched telephone network (PSTN), a global
computer network such as the internet, a local area network (LAN),
a wide-area network (WAN), or other appropriate communication equipment.
Network 230 may represent a single network or any combination of
separate networks independently connecting mobile communication
system 110, location system 120 and emergency service provider 130.
Additionally, network 230 may represent the same network as network
140.
In operation, system interface 210 receives location request 160
from communication system 120. Location request 160 may include
information identifying the broad geographic area in which mobile
phone 150 is located. For example, location request 160 may include
information identifying a particular cell tower 122 and associated
cell sector 124 of mobile communication system 110.
System interface 210 then identifies a number of antenna control
stations 220 to send a detection request 260. The identified antenna
control stations 220 may represent any or all antenna control stations
220 in location system 120 depending upon the characteristics and/or
requirements of system 100 and the location of mobile phone 150.
For example, location system 120 may couple to a large number of
antennas 112 spread across an expansive geographic area. System
interface 210 may then identify a subset of the antennas 112 as
being closest to mobile phone 150 by using approximate location
information included in location request 160, by referencing a database
containing geographic or other information about various mobile
communication systems 110, or in any other appropriate manner. System
interface 210 then communicates detection request 260 to the antenna
control stations 220 associated with the identified antennas 112.
Alternatively, location system 120 may couple to only a small number
of antennas 112 located in close proximity to one another, all of
which are used to locate mobile phone 150.
Additionally, system interface 210 may process approximate location
information received in location request 160 to produce antenna-specific
search parameters for each of identified antennas 112. System interface
210 includes the search parameters for a particular identified antenna
112 in the detection request 260 sent to the antenna station 220
associated with the identified antenna 112.
For example, in a particular embodiment of system 100, location
request 160 includes information identifying a particular cell tower
122 which received a call from mobile phone 150 and the cell sector
124 from which the call was received. System interface 210 identifies
a number of antennas 112 near the particular cell tower 122 and
cell sector 124. For each of the identified antennas 112, system
interface 210 calculates a starting azimuth at which the particular
antenna 112 would face cell sector 124. System interface 210 then
includes the starting azimuth in the detection request 260 sent
to the antenna control station 220 associated with the particular
identified antenna 112.
Upon receiving detection requests 260, each antenna control station
220 associated with an identified antenna 112, manipulates the associated
antenna 112 to detect identification signal 152. These antenna control
stations 220 then communicate to system interface 210 detection
responses 262 that include information describing the location of
mobile phone 150 in terms of the orientation, location or other
characteristics of the identified antennas 112.
After receiving detection responses 262 from antenna control stations
220 associated with identified antennas 112, system interface 210
uses the information provided in the various detection responses
262 to calculate the location of mobile phone 150. In a particular
embodiment of system 100, this includes triangulating the location
of mobile phone 150 using the location and detection orientations
of each of identified antennas 112.
System interface 210 generates a location response 162 including
information describing the location of mobile phone 150 and communicates
the location response 162 to either mobile communication system
110 or emergency service provider 130. Location response 162 may
include any suitable description of the location of mobile phone
150 including, but not limited to, the latitude and longitude of
mobile phone 150, information describing the location of mobile
phone 150 relative to a fixed geographic point of reference, and
driving directions to mobile phone 150 from the location of emergency
service provider 130.
FIG. 3 is a block diagram showing the contents and operation of
antenna control station 220 according to a particular embodiment
of system 100. Antenna control station 220 includes an antenna interface
310, a steering controller 320, and a signal detector 330. Additionally,
each antenna control station 220 is associated with a particular
antenna 112 and is capable of adjusting the orientation of the associated
antenna 112 and processing signals received by associated antenna
112.
Antenna interface 310 facilitates communication between antenna
control station 220 and system interface 210. Antenna interface
310 may comprise logic encoded in media for carrying out functions
of the system. The logic comprises functional instructions for carrying
out programmed tasks. The media comprises computer disks or other
suitable computer-readable media, application-specific integrated
circuits (ASICs), field-programmable gate arrays (FPGAs), digital
signal processors (DSPs) or other suitable specific or general purpose
processors, transmission media or other suitable media in which
logic may be encoded and utilized.
Steering controller 320 adjusts the orientation of associated antenna
112 and communicates the orientation of associated antenna 112 to
antenna interface 310 for use in detection response 262. In a particular,
embodiment of antenna control station 220, steering controller couples
to and controls a servo motor. The servo motor is located on associated
antenna 112 and directs associated antenna 112. Alternatively, steering
controller 320 may represent components for electronically steering
associated antenna 112. In general, steering controller 320 may
represent any combination of software and/or hardware suitable to
implement the functionality as described.
Signal detector 330 receives information identifying identification
signal 152. Signal detector 330 may also receive information identifying
a channel, frequency, and/or protocol, or any additional information
useful for detecting identification signal 152. Signal detector
330 determines whether associated antenna 112 has detected identification
signal 152. Signal detector 330 communicates the detection of identification
signal 152 to antenna interface 310. Signal detector 330 may represent
any combination of software and/or hardware suitable to implement
the functionality as described.
In operation, antenna interface 310 receives detection request
260 from system interface 210 which includes information identifying
identification signal 152. In a particular embodiment, detection
request 260 also includes a starting azimuth for associated antenna
112. Antenna interface 310 communicates the information identifying
identification signal 152 to signal detector 330. Antenna interface
310 may additionally communicate a starting azimuth to steering
controller 320, if so steering controller 320 directs associated
antenna 112 to the starting azimuth.
Steering controller 320 then directs associated antenna 112 using
any combination of coarse- and/or fine-grain search algorithms.
Signal detector 330 monitors all signals received by associated
antenna 112 during rotation. When signal detector 330 detects identification
signal 152, steering controller 320 then determines the orientation
of associated antenna 112. Steering controller 320 communicates
information describing the detection orientation to antenna interface
310. In a particular embodiment of antenna control station 220,
this information includes an angular azimuth. Antenna interface
310 generates a detection response 262 including information describing
the detection orientation and communicates detection response 262
to system interface 210.
FIG. 4A illustrates contents of a location request 160 according
to a particular embodiment of system 100. Location request 160 includes
identification parameters 410 and network parameters 420. Identification
parameters 410 provide information describing the particular mobile
phone 150 for which emergency service provider 130 is seeking a
location. Thus, identification parameters 410 also identify the
identification signal 152 sought by location system 120. Identification
parameters 410 may include information utilized by conventional
mobile communication systems, such as a mobile identification number
(MIN) 412 and an electronic serial number (ESN) 414, or any other
suitable information by which location system 120 can determine
the identification signal 152 associated with the mobile phone 150
in question.
Network parameters 420 provide information defining where and how
location system 120 should search for identification signal 152.
For example, network parameters 420 may indicate an approximate
location of mobile phone 150, the channel on which mobile phone
150 is communicating, the frequency at which mobile phone 150 is
communicating, the wireless communication protocol, or any other
information necessary for or helpful to limit the scope of the search
to be conducted by location system 120. Additionally, if system
100 includes multiple mobile communication systems 110, network
parameters 420 may include information identifying the particular
mobile system 100 that sent location request 160.
In a particular embodiment, network parameters 420 include a cell
number 422 identifying the cell tower 122 of mobile communication
system 110 that is in communication with mobile phone 150; a sector
number 424, identifying the cell sector 124 in which cell tower
122 received the communication from mobile phone 150; and channel
information 426, identifying the channel of mobile communication
system 110 on which mobile phone 150 is communicating.
FIG. 4B illustrates the contents of location response 162. Location
response 162 provides location information for mobile phone 150
to mobile communication system 110 or emergency service provider
130. Location response 162 includes identification parameters 410
and location parameters 430. Identification parameters 410 in location
response 162 may be identical to identification parameters 410 in
location request 160. However, for purposes of formatting, to facilitate
integration, or for any other suitable reason, identification parameters
410 may be modified from identification parameters 410. In a particular
embodiment of system 100, identification parameter 410 in location
response 162 include MIN 412 and ESN 414.
Location parameters 430 include information describing the location
of mobile phone 150. In a particular embodiment of system 100, location
parameters 430 include locational coordinates 432, representing
a latitudinal and longitudinal description of the location of mobile
phone 150, and the phone number of the nearest emergency service
provider 130 to locational coordinates 432, PSAP phone number 434.
In this embodiment, PSAP phone number 434 may be used by mobile
communication system 110 to identify and contact the most appropriate
emergency service provider 130.
FIG. 5A illustrates the contents of detection request 260 according
to a particular embodiment of system 100. Detection request 260
may include identification parameters 410 and steering parameters
510. Identification parameters 410 identify the identification signal
152 to be located. Identification parameters 410 may be identical
to identification parameters 410 and/or identification 410, but
may be altered for purposes of formatting, to facilitate integration,
or for any other suitable reason.
Steering parameters 510 provide antenna control station 220 with
information necessary or helpful to detecting identification signal
152. In a particular embodiment of detection request 260, steering
request 260 identifies the channel on which mobile phone 150 is
communicating and a starting azimuth 512 at which the antenna control
station 220 and associated antenna 112 should begin searching.
FIG. 5B illustrates the contents of detection response 262 according
to a particular embodiment. Detection response 262 includes identification
parameters 410 and detection parameters 520. Identification parameters
410 allow system interface 210 to determine the particular mobile
phone 150 to which detection response 262 applies. Identification
parameters 410 in detection response 262 may be identical to identification
parameters 410 in detection request 260. However, for purposes of
formatting, to facilitate integration, or for any other suitable
reason, identification parameters 410 in detection response 262
may be modified from identification parameters 410 in detection
response 260.
Detection parameters 520 provide information describing the location
of mobile phone 150 relative to the antenna 112 associated with
the particular antenna control station 220 that generated the detection
response 262. In FIG. 5B, detection parameters 520 include detection
orientation 522. Detection orientation 522 represents an angular
measurement of the azimuth at which the antenna 112 associated with
this particular antenna control station 220 detected identification
signal 152.
FIG. 6 is a flow chart diagramming the steps by which system interface
210 executes a location request 160 received from mobile communication
system 110 in a particular embodiment of system 100. At step 600,
system interface 210 receives a detection request 260 from mobile
communication system 110 including identification signal 152 associated
with mobile phone 150 requesting emergency services. At step 610,
system interface 210 identifies a number of antennas 112 to use
in searching for identification signal 152.
At step 620, system interface 210 generates detection requests
260 for each of identified antennas 112. System interface 210 communicates
detection requests 260 to the antenna control station 220 associated
with each of the identified antennas 112 at step 630.
Each of the identified antennas 112 locates mobile phone 150 by
detecting identification signal 152. Antenna control stations 220
associated with each of the identified antennas 112 determine the
detection orientation at which the associated antenna 112 detected
identification signal 152. Antenna control station 220 communicates
a detection response 262 including the detection orientation 432
to system interface 210. At step 640, system interface 210 receives
detection responses 262 from all the antenna control stations 220
of all of the identified antennas 112.
At step 650, system interface 210 references the detection orientations
432 included in the various detection responses 262. Based on the
locations of the various antennas 112 and their detection orientations
432, system interface 210 calculates the location of mobile phone
150 at step 660. At step 670, system interface 210 generates a location
response 162 that includes locational coordinates 432 describing
the location of mobile phone 150. System interface 210 communicates
the location response 162 to mobile communication system 110 or
emergency service provider 130 at step 680.
FIG. 7 is a flow chart diagramming the steps by which antenna control
station 220 executes a detection request 260 received from system
interface 210 in a particular embodiment of location system 120.
At step 700, antenna control station 220 receives a detection request
260 which may include identification signal 152 and a starting azimuth
512. At step 710, antenna control station 220 sets the orientation
of associated antenna 112 so that associated antenna faces the azimuth
indicated by starting azimuth 512.
Antenna control station 220 monitors the signals received by associated
antenna 112 at step 720. At step 730, antenna control station 220
determines whether associated antenna 112 detects identification
signal 152 at its current orientation. If not, antenna control station
220 adjusts the orientation of associated antennas 112 at step 740
and continues to monitor the signals received at step 720.
If associated antenna 112 does detect identification signal 152
at its current orientation, antenna control station 220 generates
detection response 262 describing the detection orientation of associated
antenna 112 at step 750. At step 760, antenna control station 220
communicates detection response 262 to system interface 210 to be
used in determining the location of mobile phone 150.
Although the present invention has been described with several
embodiments, a myriad of changes, variations, alterations, transformations,
and modifications may be suggested to one skilled in the art, and
it is intended that the present invention encompass such changes,
variations, alterations, transformations, and modifications as fall
within the scope of the appended claims. |