TECHNICAL FIELD
15 The present invention relates to localized position systems and a method of sharing a
location.
BACKGROUND
This section introduces aspects that may be helpful in facilitating a better understanding
20 of the invention. Accordingly, the statements of this section are to be read in this light
and are not to be understood as admissions about what is in the prior art or what is not
in the prior art.
There is often a need for groups of people to track each other’s position. For groups of
25 friends, this allows to find a particular person, for example for a mother to track and
find a daughter in a shopping mall.
Some automated solutions exist, but they rely on GPS visibility to determine a first
location.
30
However, GPS signals are unreliable or non accessible in indoor environments.
3
A solution is sought to address this situation.
SUMMARY
In view of the foregoing, an embodiment herein provides for a method for sharing the
location of a first device with at least one other device in an indoor environmen5 t
comprising a plurality of geolocalised radio beacons, comprising the steps of:
- said first device sensing signal strengths of said beacons
- said first device sending said sensed signals to a localizing module configured for
determining location of said first device by triangulation of said sensed signals
10 - broadcasting position of said first device to other devices previously authorized by
said first device.
An advantage of this embodiment lies in that it doesn’t require specialized locationmapping
means, such as a GPS, on the end-user terminal. Furthermore, the processing
15 and sharing of information is performed centrally allowing for greater administrative
oversight and potentially for the location environment to share complementary offers.
Another embodiment provides for a computer program product, comprising the steps of:
- receiving from a sensing device both signal strength data of surrounding radio beacons
20 and corresponding identity information
- loading location information of said identified radio beacons
- triangulating sensing device location from said location and signal strength data
- broadcasting location of device to a list of authorized apparatuses.
25 Yet another embodiment provides for a product configured for sharing the location of a
first device with at least one other device in an indoor environment comprising a
plurality of geolocalised radio beacons, said product being adapted to :
- receive from a sensing device both signal strength data of surrounding radio beacons
and corresponding identity information
30 - load location information of said identified radio beacons
- triangulate sensing device location from said location and signal strength data
- broadcast location of device to a list of authorized apparatuses.
4
These and other aspects of the embodiments herein will be better appreciated and
understood when considered in conjunction with the following description and the
accompanying drawings.
5
BRIEF DESCRIPTION OF THE FIGURES
Figure 1 is a schematic representation of an environment in a first embodiment.
Figure 2 is a schematic representation of a mobile device according to an embodiment.
Figure 3 illustrates a table of sensed beacons according to an embodiment.
10 Figure 4 is a schematic representation of a system according to the an embodiment of
the present invention.
Figure 5 illustrates a table of sensed beacons according to an embodiment.
Figure 6 illustrates a process of operating the present invention according to a variant of
the invention.
15
DETAILED DESCRIPTION OF EMBODIMENTS
The embodiments herein and the various features and advantageous details thereof are
explained more fully with reference to the non-limiting embodiments that are illustrated
in the accompanying, drawings and detailed in the following description. Descriptions
20 of well known components and processing techniques are omitted so as to not
unnecessarily obscure the embodiments herein. The examples used herein are intended
merely to facilitate an understanding of ways in which the embodiments herein may be
practiced and to further enable those of skill in the art to practice the embodiments
herein. Accordingly, the samples should not be construed as limiting the scope of the
25 embodiments herein.
The present invention is relative to a geolocalising system 1 configured for localizing
mobile devices within its perimeter and for sharing said localization to one or more
other devices which have been previously authorized.
30
With reference to figure 1, there is shown a spatial representation of an indoor
environment 2 and a plurality of radio beacons 3. The instances of the radio beacon 3
5
visible on figure 1 are referenced 3A-3F. It is to be noted that when the beacon is
referred to without a suffix, then the general element is invoked, and as such applies to
all individual beacons.
As used herein, the term indoor environment is meant broadly to include an5 y
environment at least partially physically delimited such as a residential home, a hotel, a
floor in a certain building, an office, a shopping center, a central transport station, a
hospital, an airport, a depository, a museum mall or more generally any building. Such
indoor environments are generally composed of places (or equivalently spaces) such as
10 room(s), hall(s), corridor(s), or office(s).
The environment of figure 1 may for example be that of a shopping mall. The delimited
environment 2 comprises paths 4 leading to a plurality of spaces 5. The spaces may be
open to the paths, for example open shops, or closed, for example office space or
15 maintenance areas. The environment 2 also represents a plurality of radio beacons 3A-
3F attached to the walls delimiting the paths 4 and the spaces 5.
The radio beacons 3 may for example be:
- radio emitters of a known power;
20 - wifi antennas sending out signals of a known power.
Having a power emission of a known and controlled power allows the skilled person to
evaluate distance to a sensor by comparing the sensed power of the emitted signals to a
calculated value related to natural attenuation in a room as it propagates, and allowing
for scattering signals.
25
Each beacon 5 operates on wireless radio technology: radio frequency, Wifi (IEEE
802.11), Bluetooth (IEEE 802.15.1), etc.
The radio beacon 3 also broadcasts a unique ID to be able to correlate the signal
30 received with a specific radio beacon 3.
6
In the present description, the radio beacons 3 will be using wifi technology to illustrate
an exemplary embodiment.
Figure 1 further illustrates a plurality of mobile devices 10 roaming about the
environment 2, adapted for sensing the propagated wifi signals emitted by the wif5 i
beacons 3.
Figure 2 schematically illustrates the mobile device 10 in greater details. The mobile
device 10 comprises:
10 - a network interface 11 adapted for communicating with external networks. The
network interface may be operational over Wifi frequency or mobile networks
(2G, 3G, 4G, LTE) indiscriminately.
- A radio signal sensor 13 adapted for sensing the signal strength of the signals
emitted by radio beacons 3, and in particular for sensing the Wifi signal
15 strengths emitted by the beacons 3.
- A processor 15 adapted for periodically taking the sensed signal strength from
the sensor 13 and sending it over the network interface 11.
The mobile device 10 may further comprise display means and data entry means. For
example, the mobile device 10 may be a mobile phone with appropriate signal sensing
20 technology.
The mobile device 10 is adapted to scan the identity (ID) of the beacon 3 and the
corresponding signal strength. Figure 3 illustrates an exemplary results table, showing a
list of sensed radio beacons 3 in the proximal environment of the mobile device,
25 together with unique corresponding ID of the beacon 3.
With reference to figure 4, the system 1 further comprises a geolocating system 50
comprising:
- A processor 51
30 - A beacon interface 53.
- A database 55 of beacon locations
- A localization processor 57
7
- A network interface 59, and
- A sharing authorization module 61
The beacon interface 53 is configured for powering the plurality of radio beacons 3
disposed in the environment 2, and for providing each beacon a unique beacon ID fo5 r
broadcasting with.
The database 55 of beacon locations stores references of the beacons IDs 3 deployed in
the environment 2. The position may be an absolute position or a relative position on a
10 custom grid specific to the environment 2. Indeed, before installation of the beacons,
their location is accurately measured using surveying or engineering techniques such
that the system 1 knows very accurately which beacon 3 is installed in which position.
The localization processor 57 is adapted for taking from three or more beacons 3 :
15 - the location of the referenced beacons as given by the database 55 of beacon
locations, and
- the signal strength sensed by the mobile device 10,
and is further configured for triangulating the position of the mobile device 10
using this information.
20
The localization processor 57 may be further adapted with technology for correcting for
signal scatter and bounce.
The network interface 59 is adapted for communicating with the mobile device 10, and
25 may support Wifi or mobile networking technology.
The sharing authorization module 61 comprises a list of mobile devices 10A registered
with the system 50, and corresponding mobile devices 10 which have been authorized
to share the localization information to. This is illustrated at figure 5.
30
8
The list of devices authorized to receive another device’s location may be set manually
by a system administrator, or a sign-up/confirmation process may be implemented in
this regard.
Figure 6 illustrates a typical process for working the foregoing embodiment5 .
Step S101 illustrates a mobile device 10A periodically scanning for proximate beacons
3 in the surrounding environment 2. The mobile device 10A senses the strength of the
received signal and records the beacon ID corresponding to the sensed signal, in a
10 similar fashion to the table of figure 3.
Next, the device 10A uploads the sensing results to the processor 51 of the system 50
via its own network interface 11 and the network interface 59 of the system 50 (step
S103).
15
The processor 51 then loads, at step S105, the location information for each detected
beacon by polling the beacon location database 55. At this point, each beacon ID has the
corresponding signal strength indication and real world coordinate system (in absolute
or relative terms), which may be processed by the triangulation processor 57 to arrive at
20 a triangulated position of the device 10A at the time of sensing the beacon 3 signals.
At step S109 the processor 51 subsequently or in parallel to steps S105 and S107, also
polls the sharing authorization list 57 to determine which other devices 10A the location
of the present device in question should be shared with.
25
At step S111, the processor 51 sends the location of device 10A to the other devices
authorized to receive it. The processor 51 may send raw system location coordinates as
used internally by the system 50. The processor 51 may alternatively send absolute
coordinates in a world coordinate system (eg. one equivalent to that used by GPS
30 coordinates), or a relative coordinate system specific to the environment 2. Alternatively
still, the processor 51 may convert the location to semantics, eg. on floor 2, by sephora
on south side of building.
9
At step S111, the processor may also send to authorized devices a map of the
environment and the location of device 10A superimposed on the map.
These embodiments are useful in many situation, for example:
- while waiting for a friend in a big shopping centre, to guide the friends together5 ;
- If a parent loses his/her child in a shopping centre or office park, the parent can
invoke the system to share the location of the child;
- A person looking for a specific shop or service in a mall can use this technique
to be guided to the appropriate venue.
10
In another variant of the present embodiment, the mobile 10A can also simply track
itself in an environment. This is particularly advantageous in order to find one’s
location when lost. In this case, only steps S101 to S107 need be implemented.
15 A person of skill in the art would readily recognize that steps of various abovedescribed
methods can be performed by programmed computers. Herein, some
embodiments are intended to cover program storage devices, e.g., digital data storage
media, which are machine or computer readable and encode machine-executable or
computer-executable programs of instructions where said instructions perform some or
20 all of the steps of methods described herein. The program storage devices may be, e.g.,
digital memories, magnetic storage media such as a magnetic disks or tapes, hard
drives, or optically readable digital data storage media. The embodiments are also
intended to cover computers programmed to perform said steps of methods described
herein.
25 The present inventions may be embodied in other specific apparatus and/or methods.
The described embodiments are to be considered in all respects as only illustrative and
not restrictive. In particular, the scope of the invention is indicated by the appended
claims rather than by the description and figures herein. All changes that come within
the meaning and range of equivalency of the claims are to be embraced within their
30 scope.

I/We Claim:
1. A method for sharing the location of a first device with at least one other device in an
indoor environment comprising a plurality of geolocalised radio beacons, comprising th5 e
steps of:
- said first device sensing signal strengths of said beacons;
- said first device sending said sensed signals to a localizing module configured for
determining location of said first device by triangulation of said sensed signals;
10 - broadcasting position of said first device to other devices previously authorized by said first
device.
2. Method of claim 1, wherein the identity of authorized devices is predetermined by a
request/confirmation process.
15
3. Method of claim 1, wherein the beacon sends out IEEE 802.11 (Wifi) signals.
4. Method according to any one preceding claims, wherein said localizing module is given
coordinates of the beacons and the signal strength of each as detected by said first device in
20 order to computer a location from triangulation techniques.
5. Method according to claim 4, wherein said triangulation techniques further comprises
scattering correction.
25 6. A computer program product, comprising the steps of:
- receiving from a sensing device both signal strength data of surrounding radio beacons and
corresponding identity information
- loading location information of said identified radio beacons
- triangulating sensing device location from said location and signal strength data
30 - broadcasting location of device to a list of authorized apparatuses.
7. A product (50) configured for sharing the location of a first device (10) with at least one
other device in an indoor environment (2) comprising a plurality of geolocalised radio
beacons (3), said product being adapted to :
11
- receive from a sensing device both signal strength data of surrounding radio beacons and
corresponding identity information
- load location information of said identified radio beacons
- triangulate sensing device location from said location and signal strength data
- broadcast location of device to a list of authorized apparatuses5 .
8. A product according to claim 7, configured to communication with the sensing device via
Wifi® communication.
10 9. A product according to claim 7 or 8, wherein said broadcasting is performed of a Wifi®
communication.
10. A product according to any one of the preceding claims 7 to 9, adapted to communication
with radio beacons functioning over Wifi® signals.