U.S. patent application number 14/500116 was filed with the patent office on 2015-03-26 for system and method for improving location estimates of co-located sectored cell sites for location services.
This patent application is currently assigned to BLACKBERRY LIMITED. The applicant listed for this patent is BLACKBERRY LIMITED. Invention is credited to Anand Ravindra OKA, Sean Bartholomew SIMMONS, Christopher Harris SNOW.
Application Number | 20150087334 14/500116 |
Document ID | / |
Family ID | 50339334 |
Filed Date | 2015-03-26 |
United States Patent
Application |
20150087334 |
Kind Code |
A1 |
OKA; Anand Ravindra ; et
al. |
March 26, 2015 |
System and Method For Improving Location Estimates Of Co-Located
Sectored Cell Sites For Location Services
Abstract
Improved location estimates for transceivers is described. The
location estimate of transceivers can be improved for sector
transceivers that are co-located at a sectored cell site. The
location estimate for each individual co-located sector transceiver
can be updated as a centroid of all of the co-located sector
transceivers. The location information of the transceivers can be
used to provide network location estimation to mobile devices which
do not have accurate positioning estimates.
Inventors: |
OKA; Anand Ravindra;
(Redmond, WA) ; SNOW; Christopher Harris; (Santa
Clara, CA) ; SIMMONS; Sean Bartholomew; (Waterloo,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BLACKBERRY LIMITED |
Waterloo |
|
CA |
|
|
Assignee: |
BLACKBERRY LIMITED
Waterloo
ON
|
Family ID: |
50339334 |
Appl. No.: |
14/500116 |
Filed: |
September 29, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13628571 |
Sep 27, 2012 |
8849305 |
|
|
14500116 |
|
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Current U.S.
Class: |
455/456.1 |
Current CPC
Class: |
H04W 4/023 20130101;
H04W 4/021 20130101 |
Class at
Publication: |
455/456.1 |
International
Class: |
H04W 4/02 20060101
H04W004/02 |
Claims
1. A method of improving a location estimate of transceivers, the
method comprising: identifying a plurality of transceivers
co-located at a sectored cell site each having respective location
estimates as a co-located group; determining a location of a
virtual transceiver for the co-located group by using an average of
the respective location estimates of each of the plurality of
identified transceivers; and assigning the determined location of
the virtual transceiver to each of the transceivers of the
co-located group at the sectored cell site.
2. The method of claim 1, further comprising accessing the
respective location estimates of each of the transceivers by
respective unique identifier determined to be co-located from a
data store.
3. The method of claim 1, wherein the location estimate of each of
the transceivers is determined from location information provided
from a plurality of mobile devices in communication with the
respective transceiver.
4. The method of claim 3, wherein the location estimate of each of
the transceivers comprises a respective error resulting from
determining the location as a centroid of a plurality of mobile
device locations unevenly distributed about the respective
transceiver.
5. The method of claim 1, further comprising identifying each of a
plurality of transceiverIDs as co-located transceivers by assigning
a unique virtual transceiverID to the co-located transceivers.
6. The method of claim 1, further comprising grouping the plurality
of transceivers into possible co-located groups based on a carrier
identifier associated with the transceivers wherein the co-located
groups are identified by a co-location labelling format that
identifies one or more labelling formats used when assigning the
unique identifier to the respective transceiver associated with the
carrier identifier.
7. The method of claim 6, further comprising, for each co-located
group for a carrier identifier: determining a number of the
plurality of transceivers with consistent transceiver IDs; and
identifying the plurality of transceivers with consistent
transceiver IDs as co-located transceivers based upon the labelling
format.
8. An apparatus for estimating a transceiver's location comprising:
at least one processing unit for executing instructions; and at
least one memory unit for storing instructions, the instructions
when executed by the at least one processing unit configuring the
apparatus to: identify a plurality of transceivers co-located at a
sectored cell site each having respective location estimates as a
co-located group; determine a location of a virtual transceiver for
the co-located group by using an average of the respective location
estimates of each of the plurality of identified transceivers; and
assign the determined location of the virtual transceiver to each
of the transceivers of the co-located group at the sectored cell
site.
9. The apparatus of claim 8, wherein the executed instructions
further configure the apparatus to access the respective location
estimates of each of the transceivers by respective unique
identifier determined to be co-located from a data store.
10. The apparatus of claim 8, wherein the location estimate of each
of the transceivers is determined from location information
provided from a plurality of mobile devices in communication with
the respective transceiver.
11. The apparatus of claim 10, wherein the location estimate of
each of the transceivers comprises a respective error resulting
from determining the location as a centroid of a plurality of
mobile device locations unevenly distributed about the respective
transceiver.
12. The apparatus of claim 8, further comprising identifying each
of the plurality of transceiver IDs as co-located transceivers by
assigning a unique virtual transceiver ID to the co-located
transceivers.
13. The apparatus of claim 12, further comprising grouping the
plurality of transceivers into possible co-located groups based on
a carrier identifier associated with the transceivers wherein the
co-located groups are identified by a co-location labelling format
that identifies one or more labelling formats used when assigning
the unique identifier to the respective transceiver associated with
the carrier identifier.
14. A non-transitory computer readable memory storing computer
executable instructions thereon that when executed by a processor
perform: identifying a plurality of transceivers co-located at a
sectored cell site each having respective location estimates as a
co-located group; determining a location of a virtual transceiver
for the co-located group by using an average of the respective
location estimates of each of the plurality of identified
transceivers; and assigning the determined location of the virtual
transceiver to each of the transceivers of the co-located group at
the sectored cell site.
15. The non-transitory computer readable memory of claim 14,
further comprising instructions for accessing the respective
location estimates of each of the transceivers by respective unique
identifier determined to be co-located from a data store.
16. The non-transitory computer readable memory of claim 15,
wherein the location estimate of each of the transceivers is
determined from location information provided from a plurality of
mobile devices in communication with the respective
transceiver.
17. The non-transitory computer readable memory of claim 16,
wherein the location estimate of each of the transceivers comprises
a respective error resulting from determining the location as a
centroid of a plurality of mobile device locations unevenly
distributed about the respective transceiver.
18. The non-transitory computer readable memory of claim 14,
further comprising instructions for identifying each of a plurality
of transceiverIDs as co-located transceivers by assigning a unique
virtual transceiverID to the co-located transceivers.
19. The non-transitory computer readable memory of claim 14,
further comprising instructions for grouping the plurality of
transceivers into possible co-located groups based on a carrier
identifier associated with the transceivers wherein the co-located
groups are identified by a co-location labelling format that
identifies one or more labelling formats used when assigning the
unique identifier to the respective transceiver associated with the
carrier identifier.
20. The non-transitory computer readable memory of claim 19,
further comprising instructions for, for each co-located group for
a carrier identifier: determining a number of the plurality of
transceivers with consistent transceiver IDs; and identifying the
plurality of transceivers with consistent transceiver IDs as
co-located transceivers based upon the labelling format.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 13/628,571 which issued on Sep. 30, 2014 as
U.S. Pat. No. 8,849,305, the entire disclosure of which is hereby
incorporated by reference for all purposes.
TECHNICAL FIELD
[0002] The current disclosure relates to mobile device location
services and in particular to improving location estimation of
co-located transceivers of sectored cell sites for location
services.
BACKGROUND
[0003] Mobile devices, such as smartphones, tablets and laptops
location services enable location based applications or services to
be provided on the devices. These services require that the mobile
device determine their current location, or an estimate of the
location using location technology such as a global positioning
system (GPS) receiver. However a GPS receiver or signal may not
always be available, or its accuracy too low due to the particular
radio frequency environment, and an accurate location for the
mobile device may be able to be determined.
[0004] It is possible to estimate a location of a mobile device
based on a radio scene captured by the mobile device, however an
accurate location of the associated transceivers is required to
provide location estimate. The radio scene may comprise a plurality
of cell identifiers (IDs) and associated received signal strength
indicator (RSSI) value from cellular transceivers the mobile device
is receiving signals from. If the locations of the transceivers are
known, the location of the mobile device can be estimated using
trilateration, or more generally n-lateration.
[0005] FIG. 1 depicts the use of trilateration for determining a
location of a mobile device. In FIG. 1, it is assumed that the
person 102 has a mobile device. The mobile device may communicate
with numerous cell sites 104a, 104b, 104c having transceivers
(referred to collectively as cell sites 104). If the position of
the cell sites 104 are known, and a distance 106, 106b, 106c from
each of the cell sites 104 to the person 102 is known, it is
possible to determine the location of the person using
trilateration, which is the case of n-lateration for n=3. The
signal strength of signals 108a, 108b, 108c received at the user's
mobile device from the cell sites 104 can be used to provide an
estimate of the distance the user is from the transceivers of the
respective cell sites 104. The mobile device may provide a current
radio scene to a location service that can provide the required
location information of the cell site. The location service can
perform the trilateration and return the estimate of the mobile
device's location back to the mobile device, which can then use the
estimated location as desired.
[0006] FIG. 2 depicts an illustrative representation of determining
a location of a cell site. The cell site 202 communicates with a
plurality of users 204a,204b, 204c, 204d, 204e, 204f (referred to
collectively as users 204), or more precisely the mobile devices of
the users 204, that are within a transmission radius 206 of the
transceiver of the cell site 202. If the locations of the users 204
are known as well as the distances 208a, 208b, 208c, 208d, 208e,
208f from the users 204 to the cell site 202, the location of the
cell site 202 can be determined. Additionally or alternatively, if
a large number of users provide their location information, the
location of the cell site can be estimated as a centroid of the
provided mobile device locations.
[0007] While the above technique for determining a cell site's
location as a centroid of mobile device positions works well if the
users providing their location information are evenly distributed
about the transceiver of cell site, the technique will provide a
location estimate with a larger error if the users are not evenly
located about the transceiver of the cell site, as may be the case
for co-located transceivers of sectored cell sites.
[0008] As described above, in order to provide a location service
when GPS information is not available or is inaccurate from the
mobile device, the location of cell sites must be known to use
network based location techniques. Although the wireless carriers,
or infrastructure service providers, that operate the wireless
network will know the location of the cell sites to a high degree
of accuracy and can use network based location techniques to
determine a location of a mobile device, this information is often
not available to third parties or applications that may wish to
provide location services to mobile devices. As such, it is
necessary to be able to accurately determine the location of cell
sites in a network in order to provide location services without
relying on service provider location information.
[0009] Therefore there is a need for a system and method for
improved location estimates of co-located sectored cell sites.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Further features and advantages of the present disclosure
will become apparent from the following detailed description, taken
in combination with the appended drawings, in which:
[0011] FIG. 1 depicts the use of trilateration for determining a
location of a mobile device;
[0012] FIG. 2 depicts a representation of determining a location of
a transceiver;
[0013] FIG. 3 depicts the use of trilateration for determining a
location of a mobile device with sector transceivers co-located at
sectored cell sites;
[0014] FIG. 4 depicts determining a location estimate of a sector
transceiver of a sectored cell site;
[0015] FIG. 5 depicts determining a location for a plurality of
sector transceivers in a sectored cell site;
[0016] FIG. 6 depicts a method of improving a location estimate for
co-located sector transceivers;
[0017] FIG. 7 depicts a further method of improving a location
estimate for co-located sector transceivers;
[0018] FIG. 8 depicts a method for identifying sector transceivers
that are co-located at sectored cell sites;
[0019] FIG. 9 depicts a further method for identifying sector
transceivers that are co-located at sectored cell sites;
[0020] FIG. 10 depicts a method of estimating transceiver
locations;
[0021] FIG. 11A depicts illustrative observation data;
[0022] FIG. 11B depicts illustrative location data;
[0023] FIG. 11C depicts illustrative location data with co-located
sector transceivers identified;
[0024] FIG. 12 depicts a method of updating a transceiver locations
based on received location information;
[0025] FIG. 13 depicts a method of providing a location
estimate;
[0026] FIG. 14 depicts an environment for improving a location
estimate of sector transceivers that are co-located at sectored
cell sites; and
[0027] FIG. 15 depicts an apparatus for improving an estimate of
sector transceivers that are co-located at sectored cell sites.
DETAILED DESCRIPTION
[0028] In accordance with the present disclosure, there is provided
a method of improving a location estimate of a transceivers
co-located at a sectored cell site, the method comprising:
identifying a plurality of transceivers that are co-located at the
sectored cell site; determining a location of a virtual transceiver
as an average of respective location estimates of the plurality of
identified transceivers; and assigning the determined location of
the virtual transceiver to each of the transceivers determined to
be co-located.
[0029] In accordance with the present disclosure, there is further
provided an apparatus for estimating a transceiver's location
comprising: at least one processing unit for executing
instructions; and at least one memory unit for executing
instructions, the instructions when executed by the at least one
processing unit configuring the apparatus to perform a method of
improving a location estimate of transceivers co-located at a
sectored cell site, the executing instructions configuring the
apparatus to: identify a plurality of transceivers that are
co-located at the sectored cell site; determine a location of a
virtual transceiver as an average of respective location estimates
of the plurality of identified transceivers; and assign the
determined location of the virtual transceiver to each of the
transceivers determined to be co-located.
[0030] In accordance with the present disclosure, there is further
provided a non-transitory computer readable memory storing computer
executable instructions thereon that when executed by a processor
perform a method of improving a location estimate of transceivers
co-located at a sectored cell site, the method comprising:
identifying a plurality of transceivers that are co-located at the
sectored cell site; determining a location of a virtual transceiver
as an average of respective location estimates of the plurality of
identified transceivers; and assigning the determined location of
the virtual transceiver to each of the transceivers determined to
be co-located.
[0031] Although the following discloses example methods and
apparatus including, among other components, software executed on
hardware, it should be noted that such methods and apparatus are
merely illustrative and should not be considered as limiting. For
example, it is contemplated that any or all of these hardware and
software components could be embodied exclusively in hardware,
exclusively in software, exclusively in firmware, or in any
combination of hardware, software, and/or firmware. Accordingly,
while the following describes example methods and apparatus,
persons having ordinary skill in the art will readily appreciate
that the examples provided are not the only way to implement such
methods and apparatus.
[0032] It will be appreciated that for simplicity and clarity of
illustration, where considered appropriate, reference numerals may
be repeated among the figures to indicate corresponding or
analogous elements. In addition, numerous specific details are set
forth in order to provide a thorough understanding of the
embodiments described herein. However, it will be understood by
those of ordinary skill in the art that the embodiments described
herein may be practiced without these specific details. In other
instances, well-known methods, procedures and components have not
been described in detail so as not to obscure the embodiments
described herein. Also, the scope of the teachings provided herein
is not considered to be limited to the specific description of the
embodiments provided herein. Embodiments are described below, by
way of example only, with reference to FIGS. 1 to 13.
[0033] FIG. 3 depicts the use of trilateration for determining a
location of a mobile device with sectored cell sites. Cell sites in
a cellular or mobile network may be omni-directional, as depicted
above in FIGS. 1 and 2. Omni-directional cell sites have a single
transceiver and antenna (referred to collectively as a transceiver
for simplicity) that radiates a radio frequency (RF) signal in all
directions equally. Cell sites may also be sectored. Sectored cell
sites have multiple sectors that combine to provide the desired
coverage. Sectored cell sites may comprise multiple transceivers
each having an associated sector antenna that radiates an RF signal
in a preferential direction. The transceiver and associated sector
antenna may be referred to as a sector transceiver. A sector
transceiver may include a directional antenna coupled to a base
station transceiver. The base station transceiver may be associated
with one or more directional antennas that are co-located at the
sectored cell site. The number of sector transceivers in a sectored
cell site may vary based upon the degree of sectorization; for
example three or six sectors are common but this number may vary
based upon the beam width of each sector.
[0034] FIG. 3 depicts three sectored cell sites. A first cell site
has sectors provided by sector transceivers 304a, 304b, and 304c
(referred to collectively as transceivers 304). A second cell site
has sectors provided by sector transceivers 306a, 306b, and 306c
(referred to collectively as transceivers 306. A third cell site is
has sectors provided by sector transceivers 308a, 308b, and 308c
(referred to collectively as transceivers 308). As depicted, each
of the transceivers 304, 306, 308 is represented as covering a 120
degree sector beam width, although the beam width of each sector
may individually vary based upon the coverage requirements. Each of
the individual transceivers 304, 306, 308 of the sectored cell
sites is assigned a unique identifier. Although there is no
requirement for sector transceivers that are co-located at a
sectored cell site to be labelled with consecutive IDs, it is
common for co-sector transceivers of a sectored cell site to have a
portion of the unique ID common to each co-located transceiver, and
another portion that uniquely identifies the individual
transceivers within the cell site. The particular format of the IDs
of the co-located transceivers may vary based on various factors,
including the communication standard of the transceivers, the
telecommunication company that maintains the transceivers, the
geographic location of the transceivers, the date the transceivers
were installed, the network type, as well as other possible
factors.
[0035] As an example of unique identifiers, a transceiver may be
uniquely identified by a Cell Global Identification (CGI) number. A
CGI is composed of a number associated with the country, referred
to as the mobile country code (MCC), a number associated with the
carrier or network provider in the country, referred to as the
mobile network code (MNC), a number associated with the area of the
network provided by the carrier, referred to as the location area
code (LAC) and a number identifying the transceiver within the
location area, referred to as the cell ID. It will be appreciated
that although a transmitter may be uniquely identified by a CGI
number, it is not necessary for each transceiver to transmit the
full CGI number in order for a mobile device to be able to uniquely
identify the transceiver.
[0036] Regardless of the specific requirements of uniquely
identifying transceivers, there is often a transceiver labelling
format that is used, or attempted to be used, in labelling the
unique transceiver IDs of the sectored cell site. For example, the
transceiver 304a may have an ID of 123 1, transceiver 304b may have
an ID of 123 2, and transceiver 304c may have an ID of 123 3.
[0037] Determining a location of a user 302 from the transceivers
304, 306, 308 of sectored cell sites is substantially similar to
determining the location from omni-directional cell site
transceivers, and in fact, the mobile device may not recognize that
the transceivers are sectorized. The user 102 may capture radio
scene information comprising the RSSI values and transceiver IDs
and send the radio scene information to a location service that can
retrieve the location of the transceivers and determine an estimate
of the location of the mobile device. When the locations of the
identified transceivers are known, the location service can provide
a relatively accurate location estimate of the mobile device.
However without accurate location information of the transceivers
in the network, any location estimate based on the information will
not be accurate.
[0038] FIG. 4 depicts determining a location estimate of a sector
transceiver of a sectored cell site. The location method is
substantially similar to that of determining a location estimate of
an omni-directional transceiver described above with regards to
FIG. 2. A single sector transceiver 402a of a sectored cell site is
depicted. A plurality of users 4004a, 404b, 404c, 404d that know
their respective locations and distances 406a, 406b, 406c, 406d,
which may be based on RSSI values, from the sector transceiver can
provide the information to a location service. The location service
may estimate the location of the sector transceiver 402a as a
centroid of the locations of the users. However, since the
transceiver 402a is sectored, the majority of the locations of the
users 404 will be from a preferential direction, and as such the
estimated location, depicted by circle 408a will have an associated
error 410a, which will be relatively large.
[0039] Although the location of the sector transceiver 402a is
described as being estimated as a centroid, it is contemplated that
other methods of estimating transceiver locations from user reports
are also possible. For example, the estimate may be based on
finding a good convex hull of the measurements. Irrespective of the
details of how the estimate is determined, the result will suffer
from a bias into the cone of the sector, because of the asymmetric
observation of the sector transceiver.
[0040] The antenna gain pattern of sector transceivers at a
sectored cell site is highly peaked towards the respective sector.
Hence even if users are physically present all around a sectored
cell site, they will see the sector that they happen to be in. That
is, the observation of transceivers of the sectored cell site will
predominantly come only from the particular sector. This means that
the centroid estimates of sector transceiver locations will be
heavily biased into the cone of the respective sectors. Since the
locations provided by the users are not evenly distributed around
the sectorized transceiver, an estimate of the cell site location
for the sector transceiver will have a relatively large error, in
comparison to a transceiver with users evenly distributed about it.
This error in cell site location can decrease the accuracy of a
location of a mobile device estimated using the sectored cell site
location estimates.
[0041] FIG. 5 depicts determining a location for a plurality of
sector transceivers that are co-located at a sectored cell site. In
comparison to FIG. 4, additional sector transceivers 402b, 402c are
depicted. It is assumed that the sector transceivers are
co-located, for example on the same sectored cell site. Each sector
transceiver of the cell site has an associated estimated location
408b, 408c and respective error 410b, 410c. As described in further
detail below, the location estimate for each transceiver of a
sectored cell site can be improved by combining the location
estimates of the individual sector transceivers that are co-located
at the sectored cell site. Locations of the individual sector
transceivers may be estimated from location information reported by
mobile devices providing GPS data from a respective transceiver.
Combining the location estimates for each individual sector
transceiver that is co-located at the sectored cell site will
result in a substantial portion of the individual errors cancelling
each other out, resulting in a better location estimate 508 for
each of the individual transceivers of the sectored cell site. The
location estimates of the individual transceivers 402 are combined
together to provide a location estimate of a virtual transceiver
which may be used for as the location estimate of each individual
transceivers of the sectored cell site.
[0042] Effectively, the co-located sector transceivers of sectored
a cell site are combined in a single virtual transceiver, which can
be considered as if it were an omni-directional transceiver at the
cell site. The information used for estimating the location of the
individual sector transceivers can be used in estimating the
location of the virtual transceiver, and since the group sector
transceivers may provide the coverage similar to an omni
directional cell site, the users contributing location information
should be evenly distributed about the virtual transceiver. It
should be appreciated, that the description of the virtual
transceiver is intended for explanation, and a further transceiver
is not actually created. Rather the virtual transceiver is a
representation for the group of sector transceivers co-located at a
sectored cell site. By utilizing location reports or updates
provided by mobile devices which can provide location information,
such as by using their GPS receiver, an accurate location mapping
of cell sites in the network can be determined, regardless of if
the cell sites comprise sector transceivers or not. The refined
network location mapping can then be utilized to provide location
estimation from the network for devices which do not have accurate
location information.
[0043] FIG. 6 depicts a method of improving a location estimate for
sector transceivers co-located at sectored cell sites. The method
600 begins with determining a plurality of transceivers that are
co-located (602) at a sectored cell site. Although it is possible
to determine co-located transceivers as described further below,
the method 600 assumes that there is an existing data store of
information with information identifying which transceivers are
co-located at sectored cell sites. Further it is assumed that the
data store also contains location estimates of the individual
transceivers. The location data may be provided by, or determined
from, location reports from mobile devices having accurate location
information when they see the transceivers, as described above.
[0044] Once the co-located sector transceivers are determined, the
method determines a location estimate of a virtual transceiver that
represents the co-located transceivers of the sectored cell site
(604). The location of the virtual transceiver can be determined by
averaging the location estimates of the individual transceivers of
the virtual transceiver.
[0045] Once the location is determined for the virtual transceiver,
it is assigned to each of the individual transceivers represented
by the virtual transceiver (606). Assigning the location of the
virtual transceiver to the location of the individual transceivers
that are determined to be co-located at the sectored cell site may
be accomplished in numerous ways. For example, the virtual
transceiver location could replace the existing location estimate
of each transceiver. Alternatively, the virtual transceiver
location could be associated with the individual transceivers of
the sectored cell site in addition to the original location
estimates.
[0046] Accurate mobile device location estimates can be utilized to
provide estimations of locations of transceivers of each sector of
a cell site. The locations of all of the sector transceivers that
are co-located at sectored cell site can then be utilized to refine
the location of each individual sector transceiver. The transceiver
location information can then be utilized by location services to
provide network location services to devices which do not have
accurate location information.
[0047] FIG. 7 depicts a further method of improving a location
estimate for transceivers that are co-located at sectored cell
sites. The method 700 groups co-located sector transceivers
together as one or more virtual transceivers (702). The method 700
processes each of the individual virtual transceivers (704).
Although the method depicts the processing of the virtual
transceivers as occurring sequentially, one after the other, it is
contemplated that they could be processed in parallel. For each
virtual transceiver, the method accesses location estimates for
each individual transceiver of the virtual transceiver (706) and
determines a location estimate for the virtual transceiver from the
accessed location estimates (708). The location estimate of the
virtual transceiver can be determined as a centroid of the location
estimates of the individual transceivers. After the location
estimate is determined for the virtual transceiver, it is assigned
to each of the individual transceivers of the virtual transceiver
(710). The method then returns to get another virtual transceiver
(712) unless there are no more virtual transceivers, in which case
the method is complete.
[0048] FIG. 8 depicts a method for identifying sector transceivers
that are co-located at sectored cell sites. The method 800 may be
applied to a large collection of transceiver information that
associates a unique transceiver ID with a location estimate of the
transceiver. The method 800 accesses the location information of
the transceivers (802). The transceiver information may be
generated from a collection of users that provides location
information of their positions, when known, which may be determined
for example using GPS or as described above, as well as an
indication of the transceiver visible from the location. It will be
appreciated that the visible transceivers are those transceivers
that the mobile device can receive signals from. The location
information of the transceivers is used to group transceivers into
possible virtual transceivers based on the location (804) of the
transceivers. Sector transceivers that are within a certain
distance of each other are grouped together as possible virtual
transceivers. Since a virtual transceiver provides a representation
of a plurality of sector transceivers that are co-located at a
sectored cell site, they should all have the same location;
however, due to the possible error in calculating their locations,
as described above with reference to FIG. 4, they may only be in
the same vicinity as each other. The distance used to group
possible virtual transceivers together may be provided as distance
threshold specifying the maximum distance that each transceiver of
a sectored cell site can be from each other transceiver of the
sectored cell site. The distance threshold may vary depending upon
the area covered by the cell site. As an example, the distance
threshold may be 500 meters, although other distances are possible,
such as 50 meters or more, or less than 1000 meters. Once the
transceivers are grouped into virtual transceivers based on their
locations, each virtual transceiver is processed (806). Although
depicted as being processed in a sequential manner, it is
contemplated that the processing of the virtual transceivers could
be done in parallel. For each of the virtual transceivers, the
method determines which, if any, of the transceivers have IDs that
are consistent with a co-location labelling format. The co-location
labelling may vary on various characteristics of the network.
However a co-location labelling format may be associated with one
or more characteristics of the transceiver or cell site that can be
determined from the location information. As such, it is possible
to determine one or more co-location labelling formats to use and
determine which of the transceivers match the co-location labelling
format. For example, one co-location labelling format may specify
that co-located transceivers have a first identifier portion that
is common to a carrier's transceivers within a particular location
area or cell site. Transceivers that are co-located at a sectored
cell site would have this first portion in common. The co-location
labelling format may specify that the co-located transceivers have
a second identifier portion that uniquely identifies the individual
sector transceivers within the location area or cell site. In one
identification format the last digit of a cell ID may identify the
type of sectorization, such as a value o is used for
omni-directional antenna, values 1, 2, 3 are used to identify
sectors of tri-sector or bi-sector antennas. For example,
transceivers with IDs of "123 1", "123 2" and "123 3" could be
considered as co-located based upon an example labelling scheme.
Transceivers with IDs of "147 1", "149 0", "189 2" would not be
considered co-located. Once all of the transceivers with IDs for a
cell site that are consistent with the co-located labelling format
are determined, they are identified as being co-located
transceivers (810), which may be accomplished in various manners,
including by assigning each of the identified co-located
transceivers a unique virtual transceiver ID. Once a virtual
transceiver is processed according to 808 and 810, the method may
continue with processing further virtual transceivers (812) until
all virtual transceivers have been processed, at which point the
method 800 is complete.
[0049] FIG. 9 depicts a further method for identifying sector
transceivers that are co-located at sectored cell sites. The method
800 above assumed that the location information was for
transceivers from a single wireless carrier, or network
infrastructure provider. It is possible that the location
information provides location information for transceivers of
multiple different carrier networks. Sector transceivers that are
co-located at a sectored cell site will be from the same carrier
network. As such, a further determination of the carrier network
associated with the transceiver may be used when determining if a
plurality of transceivers should form virtual transceivers. Method
900 may be used to identify sector transceivers that are co-located
at sectored cell sites from a collection of location information of
a plurality of transceivers from a plurality of carrier
networks.
[0050] The method may begin with determining or updating location
information for transceivers of cell sites (902). Determining or
updating a transceiver's location information may be done using
radio scene observations provided by mobile device in the network
that have accurate location information of their own respective
position using GPS location estimation. The mobile device can
report the ID which is associated with a transceiver and the
position of the mobile device when the ID was detected.
[0051] Transceivers that are within a co-location threshold of each
other are grouped together into location groups (904), and then
each location group is processed (906). Although depicted as being
processed sequentially, it is contemplated that the location groups
could be processed in parallel. Each location group is processed in
order to group transceivers from the location group into one or
more carrier network groups (908) so that transceivers of the same
carrier network are grouped together. Carrier information may be
provided in the transceiver ID, or may be associated with the
transceiver ID. Once the transceivers are grouped into carrier
groups, each carrier group can be processed (910). Although
depicted as being processed sequentially, it is contemplated that
the carrier groups could be processed in parallel.
[0052] For each carrier group, the IDs of the transceivers in the
carrier group checked to see if the IDs are numbered or labelled
consecutively or more broadly whether the labelling conforms to a
co-located labelling format. If the transceivers aren't
consecutively labelled (No at 912), then the transceivers in the
carrier group are not considered as co-located and processing
proceeds to get the next carrier group (920). If the transceivers
are consecutively labelled (Yes at 912), it is determined if the
number of transceivers in the carrier group matches an expected
sector scheme (914) specifying an expected number of transceivers
in a sectored cell site. For example, sector cell sites commonly
use 2, 3 or 6 sectors. As such, the expected sector scheme may
indicate that there are 2, 3 or 6 transceivers expected for a
sectored cell site. If the number of sector transceivers in the
carrier group do not match the expected sector scheme (No at 914),
then the transceivers in the carrier group are not considered as
being co-located at a sectored cell site and processing proceeds to
get the next carrier group (920) for the location group. If the
number of transceivers does match the expected sector scheme (Yes
at 914), the transceivers of the carrier group are identified as a
virtual transceiver (918). After identifying the transceivers of
the carrier group as a virtual transceiver, any further carrier
groups in the location group may be processed (920), and once all
of the carrier groups in the current location group have been
processed, another location group can be processed (922).
[0053] Once the method has identified the virtual transceivers, the
location estimates of the sectorized transceivers the virtual
transceivers can be updated, for example using one of the methods
700 or 800 described above.
[0054] FIG. 10 depicts a method of estimating transceiver
locations. The method 1000 may be used to process observation data
that is provided from a plurality of mobile devices. An
illustration of the observation data is provided in FIG. 11A. As
depicted the observation data comprises a plurality of entries each
associating a transceiver ID (TID) with location information
comprising latitude and longitude information, which would
correspond to the location of the user reporting the observation.
It is noted that the transceiver IDs in the observation data shown
in FIG. 11A are provided as an example and intended to depict
co-located transceiver IDs and non co-located transceiver IDs and
may not reflect actual transceiver ID formatting. Additionally,
only one observation for each transceiver ID is depicted; however,
in actuality there could be numerous more observations for each
individual transceiver ID. Further, only the transceiver ID and
location information is depicted; however, additional information
may be associated with each observation, including a date and time
of the observation; an error associated with the reported location;
an RSSI value for the transceiver and other information as
appropriate or required for the application.
[0055] In general, the method 1000 is a two-pass process. The first
pass uses the observation data to estimate locations of each of the
transceivers, which is used in grouping transceivers as virtual
transceivers; the resultant location data after this first pass is
depicted in FIG. 11B. The second pass of the observation data
re-calculates the locations of the transceivers taking into account
the virtual transceivers. The resultant location data after this
second pass is depicted in FIG. 11C. The second pass may only
process transceivers that are associated with a vTID.
[0056] Returning to FIG. 10, the method 1000 processes each of the
TIDs in the observation data (1002). For each TID, the location of
the corresponding TID in the location data is updated (1004).
Updating the location may be done by taking a centroid of the
location of each observation. In order to update the location
information, it may be necessary to keep track of the number of
observations that have contributed to the location so far. Once the
location data has been updated based on the observation data with
the same TID, the next TID in the observation data is processed
(1006).
[0057] Once a first pass has been made through the observation
data, the location information is processed to identify co-located
transceivers (1008). As depicted in FIG. 11B, the sector
transceivers that are co-located at a sectored cell site may be
identified by a virtual transceiver ID (vTID) that is unique to the
group of sector transceivers. Once the virtual transceivers are
identified, the location of the virtual transceivers is determined.
As described above, it is possible to determine the location of the
virtual transceivers as a centroid of the locations of the
individual transceivers of the virtual transceiver. Alternatively,
and as set forth below, the observation data can be processed again
to determine a location estimate of the virtual transceivers. The
location estimates for each transceiver associated with a vTID is
reset (1010). Each of the TIDs in the observation is then processed
again (1012). Each TID in the observation is processed to determine
if the corresponding TID is associated with a vTID in the location
information (1014), and if it is not (No at 1014) the next TID in
the observation data is processed (1018). If the TID is associated
with a vTID (Yes at 1014), then the observed location associated
with the TID is used to update the location of each of the
transceivers associated with the vTID (1016). The next TID is
processed (1018), or if there are no more CIDs to process in the
observation data the method is complete.
[0058] As is evident in FIG. 11C, which depicts the final results
of processing the observation data, the three sector transceivers
that are co-located at a sectored cell each have the same latitude
and longitude.
[0059] FIG. 12 depicts a method of updating a cell site location
based on received location information. The method 1200 assumes
that a plurality of mobile devices provide location and radio scene
information for processing. A mobile device may periodically
capture a visible radio scene, which includes the transceiver IDs
that are visible, and GPS location information at the time the
radio scene was captured. The mobile device may provide this
information as it is captured or it may store this radio scene
information and provide it in batches to a central location for
processing. Further, it is possible to have this functionality of
submitting location and radio scene information selectively enabled
or disabled by the user. The method 1200 considers processing a
single location and radio scene observation.
[0060] The method 1200 access the location and radio scene
observation (1202). The location may be determined at the mobile
devices in numerous ways, including the methods described herein,
or through the use of GPS. The radio scene identifies the
transceiver IDs of the transceivers that were seen by the mobile
device at the indicated location. Each transceiver in the radio
scene is processed (1204). For each transceiver in the radio scene,
it is determined if the location associated with the transceiver in
the observation would improve the current location estimate for the
transceiver (1206). For example, if the error associated with the
location of the observation is greater than the error associated
with the current location estimate, the observation may not improve
the location estimate. If the observation does not, or would not,
improve the location estimate (No at 1206), the next transceiver in
the radio scene is processed (1214). If the observation does, or
would, improve the location estimate (Yes at 1206), the observation
is used to update the location estimate. It is determined if the
transceiver ID is associated with a virtual transceiver (1208), and
if it is (Yes at 1208) the location of the observation is used to
updated the location estimate of the virtual transceiver (1212) and
the individual transceivers of the virtual transceiver, and the
next transceiver in the radio scene is processed (1214). If the
cell ID is not associated with a virtual transceiver (No at 1208),
the location of the observation is used to update the location
estimate of the transceiver (1210). Once the location estimate is
updated, the next transceiver in the radio scene is processed
(1214). If there are no further transceivers in the radio scene,
the method is done (1216).
[0061] FIG. 13 depicts a method of providing a location estimate by
a location service. The method 1300 uses of the location estimates
of transceivers to determine a location of a mobile device. The
method 1300 begins when a request is received from a mobile device
to determine its location (1302). The location request from the
mobile device comprises a radio scene identifying the transceivers
visible at the mobile device as well as their associated RSSI
values. The location estimate for each transceiver in the radio
scene is retrieved, if available (1304). The estimate of the mobile
device's location is then determined (1306), for example by
n-lateration using the location estimates of the visible
transceivers and the RSSI values (1306). Other techniques of
determining the mobile device's location are possible, including
taking a centroid of the locations of the visible transceivers.
Once the location is determined, it is returned to the mobile
device (1308).
[0062] Since the location request included a radio scene, and
resulted in an estimate of the location associated with the radio
scene, the location may be used to update location estimates of
transceivers in the radio scene. Although, the location estimate of
the mobile device may have a larger error than the location
estimate of the individual transceivers, it is possible that the
location estimate could improve the location estimate for one or
more of the transceivers in the radio scene. For example, if a new
transceiver is added, an initial estimate of its location can be
determined.
[0063] Each transceiver in the radio scene received in the location
request is processed (1310). For each transceiver in the radio
scene, it is determined if the determined location for the mobile
device would improve the current location estimate for the
transceiver (1312). For example, if the error associated with the
determined location for the mobile device is greater than the error
associated with the current location estimate, the determined
location may not improve the location estimate. If the determined
location does not, or would not, improve the location estimate (No
at 1312), the next transceiver in the radio scene is processed
(1320). If the determined location does, or would, improve the
location estimate (Yes at 1312), the determined location is used to
update the location estimate. It is determined if the transceiver
ID is associated with a virtual transceiver (1314), and if it is
(Yes at 1314) the determined location is used to updated the
location estimate of the virtual transceiver (1318), and the next
transceiver in the radio scene is processed (1320). If the
transceiver ID is not associated with a virtual transceiver (No at
1320), the determined location is used to update the location
estimate of the transceiver (1316). Once the location estimate is
updated, the next transceiver in the radio scene is processed
(1320). If there are no further transceivers in the radio scene,
the method is complete.
[0064] FIG. 14 depicts an environment for improving a location
estimate of a co-located transceiver in a sectored cell site. The
environment 1400 may include a data storage system 1402 for storing
observation data received from mobile devices, as well as location
data providing location estimates for transceivers of cell sites.
The data storage system 1402 is depicted as being provided by a
cluster of individual data storage systems 1402a, 1402b, 1402c. A
location service system 1404 provides a location service for
determining a location of for mobile devices based upon a radio
scene. The location service system may also receive and store
observation data, as well as determine and store location data for
transceivers. The location service system 1404 is depicted as a
cluster of a plurality of individual location service systems
1404a, 1404b, and 1404c. The location service system 1404 may
communicate with the data storage system 1402 on an internal
network or external network 1406. The location service system 1404
is connected to the network 1406, which connects the location
service system to one or more cellular networks 1408a, 1408b. Each
cellular network may be a particular type of network and/or a
particular carrier network. The cellular networks 1408a, 1408b are
coupled to cellular transceivers 1410a, 1410 that allow the
cellular networks to communicate with mobile devices 1412a, 1412b.
The mobile devices 1412a, 1412b can communicate with the location
service system 1404 in order to send location requests, and receive
the location result, as well as to provide location observations.
The mobile devices 1412a, 1412b may include GPS functionality for
receiving locating signals from a plurality of GPS satellites 1414
in order to determine their location, potentially with a high
degree of accuracy.
[0065] FIG. 15 depicts an apparatus for improving an estimate of a
co-located transceiver in a sectored cell site. The apparatus 1500
comprises at least one processing unit 1502 for executing
instructions and at least one memory unit 1504 for storing
instructions 1506. The apparatus 1500 may further comprise a
non-volatile storage unit 1508 as well as at least one input/output
interface (I/O) 1510. The I/O interface allows data to be input
into the apparatus and output from the apparatus. The instructions
1506 stored in the at least one memory unit 1504 include
instructions for configuring the apparatus to provide transceiver
location functionality 1512 as well as co-located transceiver
identification functionality 1514 as described above.
[0066] The above has described various methods, apparatus and
systems by way of examples. One skilled in the art will appreciate
that the functionality described can be provided by one or more
alternative embodiments based upon the current teachings.
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