U.S. patent application number 11/108231 was filed with the patent office on 2005-08-18 for network and method for monitoring location capabilities of a mobile station.
Invention is credited to Benes, Stanley J., DeClerck, William P., Downing, Lawrence, Gutowski, Gerald J..
Application Number | 20050180346 11/108231 |
Document ID | / |
Family ID | 25505846 |
Filed Date | 2005-08-18 |
United States Patent
Application |
20050180346 |
Kind Code |
A1 |
Benes, Stanley J. ; et
al. |
August 18, 2005 |
Network and method for monitoring location capabilities of a mobile
station
Abstract
The present invention is a communication network (100) and
method for monitoring location capabilities of mobile stations
(102) in a database (120) of a communication network. Initially,
the network receives an identification number from a mobile station
(102). If the database (120) does not include a location capability
corresponding to the identification number, then a processor (118)
requests the location capability from the mobile station (102) and
stores the requested location capability in the database (120). The
location capability includes one or more of the following
capabilities: an autonomous mode capability, an assisted mode
capability and a legacy mode capability. To retrieve an entry from
the database (120), the network reads the location capability
corresponding to the identification number from the database (120).
The network then assembles an assistance message based on the
location capability of the mobile station (102) and transmits the
assistance message to the mobile station (102).
Inventors: |
Benes, Stanley J.; (Round
Lake Beach, IL) ; DeClerck, William P.; (Palatine,
IL) ; Gutowski, Gerald J.; (Palatine, IL) ;
Downing, Lawrence; (Hoffman Estates, IL) |
Correspondence
Address: |
MOTOROLA INC
600 NORTH US HIGHWAY 45
ROOM AS437
LIBERTYVILLE
IL
60048-5343
US
|
Family ID: |
25505846 |
Appl. No.: |
11/108231 |
Filed: |
April 18, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11108231 |
Apr 18, 2005 |
|
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09962426 |
Sep 25, 2001 |
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6912395 |
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Current U.S.
Class: |
370/310 ;
455/404.2 |
Current CPC
Class: |
H04L 67/18 20130101;
H04W 64/00 20130101; H04W 4/02 20130101; H04W 4/029 20180201; H04W
60/00 20130101 |
Class at
Publication: |
370/310 ;
455/404.2 |
International
Class: |
H04B 007/00 |
Claims
1.-21. (canceled)
22. A method for monitoring location capabilities of mobile
stations using a communication network, the communication network
including a database for storing the location capabilities, the
method comprising the steps of: communicating between the
communication network and a mobile station during an initial
session comprising the sub-steps of: receiving an identification
number from a mobile station; storing a location capability of the
mobile station in the database, the location capability
corresponding to the identification number of the mobile station;
assembling a first assistance message based on the location
capability of the mobile station; and transmitting the first
assistance message to the mobile station; and communicating between
the communication network and a mobile station during a subsequent
session comprising the sub-steps of: receiving the identification
number from the mobile station; retrieving the location capability
of the mobile station from the database, the location capability
corresponding to the identification number of the mobile station;
assembling a second assistance message based on the location
capability of the mobile station; and transmitting the second
assistance message to the mobile station.
23. The method of claim 22, wherein the first and second assistance
messages including location calculation parameters of the mobile
station.
24. The method of claim 22, wherein the location capability is one
of an autonomous mode capability, an assisted mode capability and a
legacy mode capability.
25. The method of claim 22, wherein each step of receiving the
identification number includes the step of receiving a location
request.
26. The method of claim 22, further comprising the step of
receiving the location capability from the mobile station before
the step of storing the location capability of the mobile station
in the database.
27. The method of claim 26, further comprising the step of
requesting the location capability from the mobile station before
the step of receiving the location capability from the mobile
station.
28. The method of claim 22, further comprising the steps of:
receiving a response to the first assistance message after
transmitting the first assistance message to the mobile station;
and updating an operation mode of the mobile station in the
database based on the response, the operation mode being one of an
autonomous mode, an assisted mode and a legacy mode.
29. The method of claim 22, further comprising the steps of:
determining whether the mobile station is in an autonomous mode;
and bypassing the steps of assembling the first assistance message
and transmitting the first assistance message if the mobile station
is in the autonomous mode.
Description
FIELD OF THE INVENTION
[0001] The present invention generally relates to wireless
communication system that provide location-based services to a user
of a mobile station. In particular, the present invention relates
to wireless communication systems that provide location-based
services in an efficient and timely manner.
BACKGROUND OF THE INVENTION
[0002] Users of mobile stations, such as handheld portable units,
laptop units, etc., and service providers of wireless communication
networks commonly use location-based services. By knowing the
current location of the mobile station (and, thus, the user), the
service provider may tailor services provided to the user. For
example, the service provider may determine a billing rate for the
user based on the location of the mobile station when the call is
made. A service provider would typically charge less for a call
made from within a home coverage area than a call made from outside
of the home coverage area.
[0003] Current location-based services rely on a particular
sequence of messages prescribed by existing wireless communication
standards to determine a location of a mobile station. For example,
for the IS-801 standard, the mobile station originates a call and,
as a result, a wireless communication network receives a location
request. The network then requests information about the mobile
station's location capabilities from the mobile station. Next, the
mobile station responds to the network by providing its location
capabilities. Finally, the network is able to provide
location-based assistance based on the mobile station's response.
The IS-801 standard would require communication between the mobile
station and the network regarding the mobile station's location
capabilities before location-based assistance may be provided to
the mobile station, thus creating a time latency. Also, the
communication regarding the mobile station's location capabilities
would consume valuable battery power at the mobile station and
computation power of the network.
[0004] For example, many emergency systems for mobile stations and
wireless communication networks, such as the E911 emergency system,
rely on location-based services. The E911 emergency system utilizes
the current location of a mobile station to locate a caller in need
of emergency assistance. Based on the location of the mobile
station, the wireless communication network is able to contact
and/or dispatch emergency service personnel nearest to that
location. In an emergency situation, it is critical to determine
the caller's location, and other pertinent details, as quickly as
possible. To expeditiously locate a mobile station, a wireless
communication network must know the capabilities of the mobile
station so the proper location-based assistance can be
provided.
[0005] Accordingly, there is a need for a mobile station and
wireless communication network having location-based services with
minimal time latency, reduced power consumption, reduced
computational penalties, and reduced over-the-air message traffic
by managing location information about mobile stations within the
network. In addition, there is further need for a wireless
communication network that monitors and collects detailed
information about the performance of its location-based
services.
SUMMARY OF THE INVENTION
[0006] The present invention is an adaptive method for storing
location capabilities of mobile stations in a database of a
communication network. An identification number is received from a
mobile station, and an entry is created in the database
corresponding to the identification number. The location capability
is then received from the mobile station, and the location
capability is stored in the database. Next, an assistance message
based on the location capability of the mobile station is
assembled. The assistance message includes location calculation
parameters of the mobile station. The assistance message is
thereafter transmitted to the mobile station.
[0007] The present invention is also an adaptive method for
retrieving location capabilities of mobile stations from a database
of the communication network. An identification number is received
from the mobile station, and a location capability corresponding to
the identification number is read from the database. Next, an
assistance message based on the location capability of the mobile
station is assembled. The assistance message includes location
calculation parameters of the mobile station. The assistance
message is thereafter transmitted to the mobile station.
[0008] The present invention is further a non-adaptive method for
retrieving location capabilities of mobile stations from a database
of the communication network. An identification number is retrieved
from the mobile station, and a category and a sub-category of the
category are identified from the identification number. A location
capability corresponding to the identification number is then
retrieved from the database based on the category and the
sub-category. Next, an assistance message based on the location
capability of the mobile station is assembled. The assistance
message includes location calculation parameters of the mobile
station. The assistance message is thereafter transmitted to the
mobile station.
[0009] The present invention is still further a communication
network of a wireless communication system for monitoring location
capabilities of mobile stations. The communication network
comprises a database and a processor coupled to the database. The
database stores location capabilities of a mobile station based on
an identification number of the mobile station. The location
capability includes one or more of the following capabilities: an
autonomous mode capability, an assisted mode capability and a
legacy mode capability. The processor sends an assistance message
based on the location capability to the mobile station. The
assistance message includes location calculation parameters of the
mobile station. If the database does not include the location
capability, then the processor requests the location capability
from the mobile station and stores the mobile location capability
in the database.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a block diagram representing a wireless
communication system that may be adapted to operate in accordance
with the preferred embodiments of the present invention.
[0011] FIG. 2 is a flow diagram representing an adaptive method for
determining and storing location capabilities of a mobile
station.
[0012] FIG. 3 is a flow diagram representing a non-adaptive method
for determining and storing location capabilities of a mobile
station.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] The present invention utilizes previously acquired or a
priori information about mobile stations, such as their location
capabilities. One embodiment is an adaptive method and
communication network for monitoring location capabilities of
mobile stations. The communication network includes a database that
is capable of storing information about each mobile station
communicating with the communication network. Once the
communication network receives information about a mobile station,
the communication network stores the information in its database.
Anytime thereafter, the communication network may retrieve the
information from the database without disturbing the mobile station
or tying-up the communication lines between the communication
network and the mobile station. Accordingly, the adaptive method
and communication network of the present invention minimizes time
latency, reduces power consumption of the mobile station, reduces
computational penalties subjected to the communication network, and
reduces over-the-air message traffic.
[0014] Another embodiment of the present invention is a
non-adaptive method and communication network for monitoring
location capabilities of mobile stations in a database of a
communication network. The database of this non-adaptive method and
communication network is not modified automatically during
operation, but can be modified or updated by a system operator of a
service provider. The database includes a significant amount of
information. To easily sort through and access such information,
the information is organized into general categories in which each
general category is organized into smaller sub-categories.
Accordingly, the non-adaptive method and communication network of
the present invention facilitates management of a large database of
information about mobile stations.
[0015] Referring to FIG. 1, there is provided a wireless
communication system 100 that may be adapted to operate in
accordance with the preferred embodiments of the present invention.
The wireless communication system 100 includes a plurality of
mobile stations, such as mobile station 102 shown in FIG. 1. Each
mobile station 102 has an assigned identification number, such as
an Electronic Serial Number ("ESN") or an International Subscriber
Mobile Identity ("IMSI"). In addition, each mobile station 102 may
use any type of position estimation system to determine its
location, such as a terrestrial positioning system, a celestial
positioning system, or a combination of these systems. Terrestrial
positioning systems utilize various techniques including, but not
limited to, a forward link trilateration ("FLT") technique, an
advanced forward link trilateration ("AFLT") technique, an
amplitude difference, angle of arrival ("AD-AOA") technique, or an
enhanced observed time difference ("EOTD") technique. A global
positioning system ("GPS") is an example of a celestial positioning
system.
[0016] In addition to the mobile station 102, the wireless
communication system 100 includes a communication network having
one or more of each of the following equipment: a base transceiver
station ("BTS") 104, a base station controller ("BSC") 106, a
mobile switching center/visitor location register ("MSC/VLR") 108,
and an interoperability center 110. The BTS 104 is a wireless voice
and/or data link, typically a radio tower, connecting the mobile
station 102 to the remainder of the communication network. The BSC
106 is a high capacity switch that provides control functions such
as handover, cell configuration data, and control of power levels
in the BTS 104. The MSC/VLR 108 routes calls to and from the mobile
station 102 as well as tracking location information of the mobile
station. The MSC part of the MSC/VLR 108 controls calls to and from
other telephone and data systems, and performs functions such as
toll ticketing, network interfacing, and common channel signaling.
The VLR part of the MSC/VLR 108 stores temporary information about
the location of the mobile station 102 within a given area served
by the MSC part of the MSC/VLR. The interoperability center 110
provides proper conversion of voice and/or data signals of the
mobile station 102 to and from another communication protocol, if
necessary. Each of the above elements of the wireless
infrastructure is commercially available from Motorola, Inc. of
Schaumburg, Ill.
[0017] The communication network of the wireless communication
system 100 may also include one or more of the following equipment:
a Home Location Register ("HLR") 112, a Mobile Position Center
("MPC") 114, and a Position Determining Entity ("PDE") 116. The HLR
112 stores and manages subscriber information relevant to
provisioning of telecommunication services independently of the
actual location of the subscriber in the system, thus, allowing for
roaming between telecommunication systems. The MPC 114 (a.k.a.
GMLC) is a mobile location center positioned, like a controller or
gateway, between an Internet and PDE's 116. The PDE 116 (a.k.a.
SMLC) provides location calculation parameters to position
estimation systems; analyzes pseudo ranges from celestial and
terrestrial equipment; and returns latitude, longitude and
identification information to the MPC 114. The location calculation
parameters are used by the mobile station 102 to determine its
location and include, but are not limited to, information about
visible satellites, visible BTS's, signal phase, signal
frequencies, etc.
[0018] The communication network of the wireless communication
system 100 further includes a processor 118 and a database 120
coupled to the processor. The database 120 may store a location
capability of each mobile station 102 based on an identification
number of the mobile station. The possible location capabilities of
the mobile station 102 include an autonomous mode capability, an
assisted mode capability and a legacy mode capability. The database
120 may also store an operation mode of the mobile station 102
based on the identification number in which the operation mode is
an autonomous mode, an assisted mode or a legacy mode. For the
autonomous mode or capability, the mobile station 102 determines
its location without assistance from the communication network. For
the assisted mode or capability, the mobile station 102 determines
its location with the assistance of certain information received
from the communication network. For the legacy mode or capability,
the wireless network determines the mobile station's location.
[0019] In addition, the database 120 has the capacity to store
statistical information about the mobile station 102. Examples of
such statistical information include, but are not limited to,
penetration of various location technologies, accuracy of deployed
technologies, verification of meeting minimum operational
requirements, and discrimination of specific device information,
such as AGPS capable phones versus legacy phones. Information about
the accuracy of deployed technologies includes absolute accuracy in
metric units, or instantaneous and/or cumulative location
confidence data obtained from deployed mobile stations.
[0020] For example, the database 120 may store accuracy ratings for
location estimation systems such as circular error probability
("CEP") and spherical error probability ("SEP"). The CEP defines
the radius of a circle that represents a 50 percent probability of
a position lying in that circle. The SEP probability is similar
except that it represents three-dimensional accuracy because it
defines the radius of a sphere. For the preferred embodiments, the
database 120 stores accuracy ratings for GPS, such as an
instantaneous circular error probability and a cumulative circular
error probability.
[0021] The established database 120 can be analyzed to extract
mobile station population information that could be helpful to a
service provider. For example, the database 120 could provide the
service provider with information about the number of mobile
stations 102 in a wireless communication system and the type of
location technology used by each mobile station. The database 120
could also provide information demonstrating compliance by the
service provider with FCC mandates and the overall penetration of
GPS-capable mobiles in the system.
[0022] The processor 118 may be coupled to, or integrated within,
any part of the communication network, such as the HLR 112, the MPC
114 and the PDE 116. Also, the processor 118 may send an assistance
message based on the location capability of the mobile station 102
to the mobile station. For the preferred embodiment, the assistance
message includes a location of the mobile station 102. In addition,
the processor 118 may request the location capability of the mobile
station 102 from the mobile station and store the requested
location capability in the database 120 if the database does not
include the location capability.
[0023] As stated above, the possible location capabilities of the
mobile station 102 include an assisted mode capability, a legacy
mode capability, and an autonomous mode capability. A mobile
station 102 having the assisted mode capability or legacy mode
capability would require assistance from the communication network.
The communication network would need to know the mobile station's
location capability for the assisted and legacy modes and, thus,
the mobile station 102 that uses the assisted mode and/or the
legacy mode would benefit significantly from the present invention.
A mobile station 102 having the autonomous mode capability will
determine its location without assistance from the communication
network, but would still benefit from the present invention by
improved performance and/or reduced bandwidth requirements.
[0024] Referring to FIG. 2, there is provided a flow chart
representing an adaptive process for monitoring information about
mobile stations, particularly location capabilities and the like,
in accordance with a first preferred embodiment of the present
invention. For the first preferred embodiment, the processor 118
and database 120 reside in the PDE 116. The process starts at step
202 and, then, each mobile station 102 transmits its identification
number to a communication network as soon as a call is initiated at
step 204. If the call requires location information, the MSC/VLR
108 sends the location request and forwards the identification
number to the MPC 114 via a messaging protocol. The MPC 114 passes
the identification number to the PDE 116.
[0025] The processor 118 residing in the PDE 116 monitors and
passes the incoming identification number to the database 120 at
step 206. If the identification number is new, i.e., not in the
database, then the processor 118 creates an entry for the
identification number in a sorted list at step 208, and instructs
the PDE 116 to request the location capabilities of the mobile
station 102 at step 210. When the processor 118 receives a response
from the mobile station 102 at step 212, the processor 118
determines the location capabilities from the response and records
the location capabilities in the database 120 at step 214. Next,
the processor 118 assembles an assistance message at step 216. In
particular, the processor 118 marks assistance information
associated with that identification number as aid information
required by the user of the mobile station 102. The processor 118
transmits the assistance message to the mobile station 102 at step
218 and, then, receives a response to the assistance message at
step 220. If the mobile station 102 does not accept the response to
the assistance message at step 222, then the processor 118 must
repeat the steps of obtaining the MS capabilities and
assembling/transmitting the assistance message, i.e., steps 210
through 220. If the mobile station 102 accepts the response to the
assistance message at step 222, then the processor 118 updates an
operation mode field of the database 120 at step 224.
[0026] After creating an entry for a particular identification
number in the database 120, the processor 118 may read the location
capabilities of the corresponding mobile station 102 from the
database any time thereafter at step 226, thus avoiding the task of
requesting this information from the mobile station. Specifically,
the process starts at step 202 and, then, each mobile station 102
transmits its identification number to a communication network at
step 204. The processor 118 monitors and passes the incoming
identification number to the database 120 at step 206. If the
identification number is not new, i.e., is in the database, then
the processor 118 reads the location capabilities of the mobile
station 102 from the database at step 226. Thereafter, similar to
the entry creating process described above, the processor 118
assembles an assistance message at step 216, transmits the
assistance message to the mobile station 102 at step 218, and
receives a response to the assistance message at step 220. If the
response to the assistance message is not accepted by the mobile
station 102 at step 222, then the processor 118 may repeat either
(1) steps 210 through 220 to request the location capabilities
again from the mobile station 102, or (2) steps 226, 216, 218 and
220 to re-read the location capabilities from the database 120. For
the preferred embodiment shown in FIG. 3, the processor 118 repeats
steps 210 through 220.
[0027] The processor 118 determines whether the mobile station 102
is operating in an assisted, autonomous or legacy mode.
Specifically, a mobile station 102 in an autonomous mode does not
require an assistance message. Therefore, at step 228, the
processor 118 determines whether the operation mode of the mobile
station 102 is an autonomous mode. If a timer is running, then the
mobile station 102 is operating in an autonomous mode at step 228.
In the preferred embodiment, the timer is a function integrated
within the processor 118. The processor 118 then bypasses the steps
of assembling and transmitting the assistance message, i.e., steps
216 and 218, and expects to receive a message indicating the mobile
station's location at step 220.
[0028] The timer described above is controlled at steps 230 through
234 of FIG. 2. At step 230, the processor 118 determines whether
the mobile station 102 is operating in an assisted, autonomous or
legacy mode. If the mobile station 102 is operating in an
autonomous mode, then the timer is set/reset at step 232 so that it
is running. If the mobile station 102 is operating in an assisted
mode or a legacy mode, then the timer is frozen at step 234 so that
it is not running.
[0029] For the preferred embodiments, the timer resets after a
predetermined time period so that the processor 118 will assemble
and transmit the assistance message at steps 216 and 218. Certain
mobile stations 102 may switch between an autonomous mode and
another mode, such as an assisted mode, dependent upon various
conditions. Thus, processor 118 uses the timer to periodically
switch back to assembling and transmitting the assistance message
for those situations in which the mobile station 102 is no longer
operating in the autonomous mode.
[0030] As stated above, the database 120 has the capacity to store
statistical information about the mobile station 102, such as
accuracy ratings for location estimation systems such as circular
error probability ("CEP") and spherical error probability ("SEP").
For the preferred embodiments, the database 120 stores accuracy
ratings for GPS, such as an instantaneous circular error
probability and a cumulative circular error probability. In
particular, the processor 118 establishes fields in the database
120 for instantaneous and cumulative Circular Error Probability
("CEP") for the mobile stations 102. At the end of the location
attempt, the processor 118 records the instantaneous CEP in the
database 120 at step 236 and updates the cumulative CEP in the
database at step 238. Thereafter, the process terminates at step
240.
[0031] As more users use the network and method described herein,
the information content of the database 120 will build so that the
requests for location capabilities will only be necessary for
servicing new mobile stations 102, including new roamers, in the
wireless communication system. Additionally, the present invention
will reduce the message traffic and support required for assistance
mode or legacy mode mobile stations making repeated location
requests.
[0032] Referring to FIG. 3, there is provided a flow chart
representing a non-adaptive process for monitoring information
about mobile stations, particularly location capabilities and the
like, in accordance with a second preferred embodiment of the
present invention. Similar to the first preferred embodiment, the
processor 118 and database 120 reside in the PDE 116 for the second
preferred embodiment. Also, the non-adaptive process of the second
preferred embodiment uses a simple look-up table based on a
category, such as manufacturers, and a sub-category, such as serial
numbers.
[0033] The process starts at step 302 and, then, each mobile
station 102 transmits its identification number to a communication
network as soon as a call is initiated at step 304. When the mobile
station's identification number is passed to the PDE 116, the
processor 118 identifies the manufacturer of the mobile station 102
from the manufacturer bit field of the identification number as
well as a serial number of the mobile station from a serial number
bit field of the identification number at step 306. The processor
118 then checks the database 120 to see if information about
location capable mobile stations from the identified manufacturer
is available at step 308. If information is not available, the
processor 118 requests a location capability from the mobile
station 102 and receives the location capability from the mobile
station at steps 310 and 312, respectively. If the manufacturer is
included in the database 120, the processor 118 queries the
database 120 to see if there is a location capability for the
serial number associated with the identification number at step
314. If information is not available, the processor 118 requests a
location capability from the mobile station and receives the
location capability from the mobile station at steps 310 and 312,
respectively. If the information is available, the processor 118
reads the location capabilities of the mobile station 102 from the
database 120 at step 316. Next, the processor 118 assembles an
assistance message at step 318, and transmits the assistance
message to the mobile station 102 at step 320. Thereafter, the
process terminates at step 322.
[0034] The database 120 of the preferred embodiments includes
mobile information to improve message traffic and minimizes time
latency for determining the location of any mobile station 102
operating in an assisted mode or legacy mode. The database 120 may
also include priority identification numbers corresponding to users
who require or desire additional assistance in an emergency
situation. For example, one priority identification number entry in
the database 120 might identify a user with a serious heart
condition. If an emergency call arrives from that identification
number, the appropriate response personnel can be alerted to a
possible cardiac event without receiving such information from the
call originator.
[0035] While the preferred embodiments of the invention have been
illustrated and described, it is to be understood that the
invention is not so limited. Numerous modifications, changes,
variations, substitutions and equivalents will occur to those
* * * * *