Title of Invention

METHOD FOR LOCALIZATION OF MOBILE TERMINALS

Abstract The geographical position (PL. Pn), or measured information (mi) from which the geographical position (PL. Pn) may be deduced, of a mobile terminal is determined by means of requests (anf) to the terminal (EL'. En) and positional information (pi) or measured information transmitted to a control device (PF). The speed of displacement (kv) of the mobile terminal (EL. En) is determined from the transmitted positional information (pi) or measured information (mi) and the frequency of requests (anf) controlled depending on the determined speed of displacement (kv) of the mobile terminal (EL. En). The communication exchange, in particular, for mobile terminals (EL. En) with low speeds of displacement (kv) is therefore significantly reduced and the mobile terminals (EL En) and central devices provided with dynamic load reduction.
Full Text In location/position based applications, e.g. conference management or communication management for hotels, it is necessary to determine the geographical position of associated or assigned mobile terminals. For this purpose the mobile terminals are increasingly equipped with functions with the aid of which they are able to determine their geographical position. For example GPS receivers are integrated in the mobile terminals with the aid of which the geographical position can be determined. Other methods are also used e.g. for determining the position of the corresponding mobile terminal by measuring the levels of different transmission stations. All these methods and functions are initiated by means of queries to the respective mobile terminal, or its position/positional information is interrogated. These queries and interrogations are usually performed by a central device in which the location based applications are realized.
The queries are accordingly issued continuously, i.e. in a defined time schedule. In order to be able to record the geographical position of mobile terminals that are displaced, and particularly those that are displaced relatively rapidly, continuous queries are necessary at short intervals or within a fairly short time schedule. In particular when it is necessary to query a plurality of mobile terminals, this leads to an increased transmission of information, with the transmission systems and the information-processing components of the central device being subjected to a considerable dynamic load and even being overloaded.
The object underlying the invention is to improve the geographical localization of mobile terminals. This object is achieved by the features of claims 1 and 2 as well as 10 and 11.
A significant advantage of the inventive methods is that the queries to mobile terminals that are either not displaced or displaced slowly can take place at long intervals and thus the wireless transmission systems and the

position- and position-information-processing components of a central device are relieved of a considerable dynamic load. This load-reduction effect is reinforced by most terminals being displaced at low speeds. A further advantage of the inventive methods is that the speed of displacement of the mobile terminals is determined and this information can be provided to the location based applications in addition to the position of the terminals. Applications for which this additional information is advantageous include applications that include roaming functions.
Advantageous developments of the inventive methods may be found in the dependent claims.
The invention is described in more detail below with reference to two appended drawings, in which
Figure 1 shows a topology in which the invention is realized; and Figure 2 shows a flow chart explaining the inventive method to accompany the topology realized in Figure 1.
Figure 1 shows a communication platform PF in which applications AP for the terminals El.En shown are realized. For the exemplary embodiment it is assumed that the whereabouts or geographical position Pl.Pn of the terminals El.En and/or of the users of the terminals El.En is to be determined for the applications AP in accordance with the inventive methods. Such applications AP include for example a conference application or an application AP for communication in hotels or an application intended for dealing with emergency situations. The platform PF is embodied for example as a server, with such a server mostly being realized by a computer system or a personal computer.

The terminals El.En are represented in the example by cordless terminals which are embodied in accordance with the DECT standard with regard to radio interface and transmission protocol.
Alternatively other wireless or mobile radio methods are possible in accordance for example with a wireless LAN method or a Bluetooth method or a GPRS method or a UMTS method. The mobile terminals EL.En can also be hardwired to the platform through a communication network (not shown), whereby the communication networks can be embodied as packet-based or time—division-multiplex-based (not shown).
In the exemplary embodiment middleware MW is provided in the platform PF for connection of the terminals El.En, by means of which the physical and protocol properties are realized in accordance with the terminals EL.En provided. In the terminals El.En conforming to the DECT method according to the exemplary embodiment the physical and protocol DECT interface - indicated in Figure 1 by the abbreviation DECT - is realized by the middleware MW. The middleware is to be embodied accordingly in the case of other mobile terminals El.En.
For the inventive method it is assumed in the exemplary embodiment that a GPS function GPS (Global Positioning System) - referred to as GPS in Figure 1 - is used in the terminals El.En in order to determine the geographical position Pl.Pn of same. A GPS receiver is provided for this purpose with the aid of which the position Pl.Pn of the terminals El.En is determined in accordance with the coordinate system. The position Pl.Pn of the terminals El.En is unambiguously determined using the positional information pi established by the GPS function GPS.
Alternatively level measurements of the received radio signals - not shown - can be performed in order to determine the position Pl.Pn of the terminals El.En. The radio signal levels of two radio transmitters are advantageously measured,

since the geographical position Pl.Pn of the terminals EL.En can be determined in this way from the known locations of the radio transmitters and the level of the received radio signals. In hardwired mobile terminals EL.En the position PL.Pn of the mobile terminals El.En can be determined by establishing at which network access point, the position of which is known, the respective mobile terminal El.En is currently connected - not shown in Figure 1 If the terminal El.En is connected to the platform PF via a communication network, the position Pl.Pn of said terminal El.En can be determined with the aid of the communication network components such as switching equipment or gatekeepers, for example, and the positional information pi generated in this way can be forwarded to the platform PF, with the communication network components being interrogated by the platform PF for the position Pl.Pn of the terminals El.En. If the terminals El.En are connected directly to the platform PF the position Pl.Pn of the terminals El.En is determined by the platform PF itself.
The inventive method described in Figure 2 using a flow chart is realized in the middleware MW of the platform PF and in the terminals El.En principally by technical programming means, with a position routine PR being provided for this purpose in the terminals El.En.
In the flow chart shown in Figure 2 a terminal E and the platform PF are each indicated by a dash-dotted line, with any one of the terminals El.En being represented by the terminal E.
As has already been stated it is necessary for certain applications AP that the current/updated geographical position Pl.Pn of the mobile terminals El.En is determined. For this purpose a query anf is transmitted by the platform PF to the terminal E concerned, with the query anf containing an item of information ip that shows the terminal E concerned that it is to determine its actual position Pl.Pn and generate an item of positional information pi. Upon receipt of the query anf in

the terminal E concerned the terminal E determines its geographical position PL.Pn in accordance with the exemplary embodiment with the aid of the GPS function GPS. The positional information pi determined in this way is transferred/transmitted wirelessly to the platform PF by means of a response res via the DECT function DECT - indicated in Figures 1 and 2 by the abbreviation DECT.
The position PL.Pn of the terminal E concerned or the terminals E concerned -indicated in Figure 2 by the abbreviation PER - is determined several times -indicated in Figure 2 by the abbreviation n x PER, whereby these initial queries anf can be performed at regular i.e. equal intervals t or also irregularly. The speed of displacement kv of the terminal E concerned is determined/calculated using the n transmitted positional information pi in the platform PF. The interval t of the individual queries anf and the positional information pi are incorporated in the calculation. In accordance with the invention, depending on the determined speed of displacement kv of the terminal E concerned the frequency of further queries anf to the mobile terminal E concerned is controlled. This means that at a high speed of displacement kv of the mobile terminal E concerned queries anf to the mobile terminal E are initialized more frequently - i.e. at shorter intervals t' -than at a lower speed of displacement of the mobile terminal E concerned. It is assumed for the purposes of the exemplary embodiment that the mobile terminal E concerned has a low speed of displacement kv and therefore the intervals t1 of the subsequent queries anf are larger compared to the initial intervals t -indicated in Figure 2 by the abbreviation t1 In an alternative embodiment of the invention (not shown) the position PL.Pn of the terminal E concerned is not determined directly in the terminals E, but instead the radio signal level measurements already described above are performed and the measured levels are transmitted to the platform PF as measured information

mi - indicated in Figure 2 by the abbreviation mi. In the platform both the position P1..Pn and the speed of displacement kv of the terminals E concerned are determined/calculated using the transmitted levels, with a distance to the particular radio transmitter being determined from the measured level.
Controlling the frequency of the queries anf is advantageous since particularly at a low speed of displacement kv of the mobile terminals E concerned the frequency of the queries anf can be reduced to a minimum and the communication exchange between the mobile terminals E concerned and the platform PF Is thereby significantly reduced. Thus the mobile terminals E and the platform PF are relieved of a considerable dynamic load and consequently the mostly scarce resources in the mobile terminals E and in the platform PF can be used more effectively and/or the resources that become free are available for other uses/applications AP.
The inventive methods are not limited to the exemplary embodiment, but can be employed in all systems in which the recording of the position of the terminals is to be updated in order to influence/control further actions using this updated position as part of applications or functions.





We Claim:-
1. A method for localizing at least one mobile terminal (EL.En),
- in which by means of queries (anf) to the mobile terminal (EL.En) the mobile
terminal (EL.En) determines its geographical position (PL.Pn) and transmits an item of position information (pi),
- in which the speed of displacement (kv) of the mobile terminal (EL.En) is
determined from the transmitted positional information (pi), and
- in which the frequency of the queries (anf) is controlled as a function of the
determined speed of displacement (kv) of the mobile terminal.
2. A method for localizing at least one mobile terminal (EL.En),
- in which by means of queries (anf) to the mobile terminal (EL.En) the mobile
terminal (EL.En) determines an item of measured information (mi) for determining its geographical position (PL.Pn) and transmits said measured information (mi),
- in which the position (PL.Pn) of the mobile terminal (EL.En) and the speed of
displacement (kv) of the mobile terminal (EL.En) is determined from the transmitted measured information (mi), and
- in which the frequency of the queries (anf) is controlled as a function of the
determined speed of displacement (kv) of the mobile terminal.
3. The method as claimed in claim 1 or 2, wherein the queries (anf) to the mobile
terminal (EL.En) are controlled by a communication platform (KF), and the
position (PL.Pn) and/or the speed of displacement (kv) in the communication
platform (PF) for the particular terminal (EL.En) is determined from the
transmitted measured information or positional information (pi) transmitted in the
context of the queries (anf).

4. The method as claimed in one of claims 1 to 3, wherein the frequency of the
queries (anf) is increased with a rising speed of displacement (kv) and reduced
with a falling speed of displacement (kv).
5. The method as claimed in one of claims 1 to 4, wherein the frequency of the
queries (anf) is additionally controlled as a function of an application (AP)
incorporating the position (P1..Pn) of the mobile terminal (E1..En).
6. The method as claimed in one of the preceding claims, wherein the position
(PL.Pn) of the mobile terminal (EL.En) is determined with the aid of a GPS
function (GPS).
7. The method as claimed in one of the preceding claims, wherein in the mobile
terminal (EL.En) the measured information (mi) is determined by level
measurement of a signal received from at least one sender.
8. The method as claimed in one of the preceding claims, wherein for hardwired
mobile terminals (EL.En) the measured information (mi) is represented by
communication network information, with the communication network information
revealing the connection to which the mobile terminal (EL.En) is currently
connected.
9. The method as claimed in one of the preceding claims, wherein the queries
(anf) are directed to mobile DECT, wireless LAN, UMTS, or GPRS, or PDA
terminals (EL.En).
10. A communication platform for cooperation with mobile terminals (EL.En) for
localizing at least one mobile terminal (E1..En),
- having means to issue queries (anf) to the mobile terminal (EL.En) to determine its geographical position (PL.Pn) and for transmitting an item of positional information (pi),

- having means to determine the speed of displacement (kv) from the transmitted
positional information (pi) of the mobile terminal (EL.En), and
- having means to control the frequency of the queries (anf) as a function of the
determined speed of displacement (kv) of the mobile terminal (E1 ..En).
11. A communication platform for cooperation with mobile terminals (E1..En) for
localizing at least one mobile terminal (E1 ..En),
- having means through queries (anf) to the mobile terminal (EL.En) to
determine an item of measured information (mi) for determining its geographical position (P1..Pn) and for transmitting the measured information (mi),
- having means to determine the position (P1 ..Pn) and the speed of displacement
(kv) of the mobile terminal (EL.En) from the transmitted measured information (mi), and
- having means to control the frequency of the queries (anf) as a function of the
determined speed of displacement (kv) of the mobile terminal (E1 ..En).
12. A method for localizing at least one mobile terminal substantially as
hereinbefore described with reference to the accompanying drawings.
13. A communication platform for cooperation with mobile terminals (EL.En)
for localizing at least one mobile terminal substantially as hereinbefore described
with reference to the accompanying drawings.



Documents:


Patent Number 259554
Indian Patent Application Number 1/DELNP/2008
PG Journal Number 12/2014
Publication Date 21-Mar-2014
Grant Date 18-Mar-2014
Date of Filing 01-Jan-2008
Name of Patentee SIEMENS ENTERPRISE COMMUNICATIONS GMBH & CO. KG.
Applicant Address HOFMANNSTR. 51, 81379 MUNCHEN, GERMANY.
Inventors:
# Inventor's Name Inventor's Address
1 BOZIONEK; BRUNO JOHANNESSTRAßE 33, 33178 BORCHEN, GERMANY.
PCT International Classification Number H04Q 7/38
PCT International Application Number PCT/EP2006/063861
PCT International Filing date 2006-07-04
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10 2005 035 748.2 2005-07-29 Germany