WO2010078968A1

WO2010078968A1 - Location-based charging

Info

Publication number: WO2010078968A1
Application number: PCT/EP2009/050240
Authority: WO
Inventors: Jarko Tapio Henrik Niemenmaa; Ville Matti Harri Ruutu
Original assignee: Nokia Siemens Networks Oy
Current assignee: Nokia Solutions and Networks Oy
Priority date: 2009-01-12
Filing date: 2009-01-12
Publication date: 2010-07-15
Anticipated expiration: 2011-07-12

Abstract

A method and apparatus for enabling location-based charging for mobile communication services is described. When a user device is used to access a mobile communication service, passive location data for the user device is obtained from a passive data collector. The passive location data is compared with a special tariff area, such as a home zone or an office zone, to determine the tariff that should be applied for the service. A charging module is then used to calculate a charge.

Description

Title

Location-Based Charging

The present invention is related to the field of charging for mobile communication services. In particular, the invention is related to the use of special tariff areas in charging for mobile communication services.

The concept of special tariff areas for mobile communications is known. Special tariff areas define geographical areas where a special tariff is used for mobile communication services, such as voice calls, SMS, data connections etc.

One example of a special tariff area is the so-called home zone. Typically, a home zone is defined as the area within a user's home. When the user makes a call within his/her home, a special tariff is used. Typically, the home zone tariff is set to be similar to the cost of using a land line. In this way, mobile communication operators can compete with fixed line operators in a home environment, whilst charging higher rates when the same user uses their mobile communication device outside the home zone. Of course, the concept of special tariff areas is not restricted to home zones; in principle, any area could be defined as a special tariff area. Another example of a special tariff area is an office zone. Further examples include areas such as university campuses, city suburbs, and city centres.

Figure 1 is a flow chart showing an exemplary algorithm, indicated generally by the reference numeral 1 , showing, in broad terms, how a charging module may determine whether or not a special tariff should be used for a particular service.

The algorithm 1 starts at step 2, where the charging module is informed that a call (or some other use of a mobile communication system for which a charge is to be made) is initiated. Next, the charging module polls the device making the call to determine the location of that device in a location determination step 4. The location information obtained in the step 4 is used by the charging module to determine whether the user device is within a special charging area (such as a home zone) in step 6. On the basis of the location of the device, the appropriate tariff for the service being used is selected and the appropriate charge is calculated in step 8.

Figure 2 shows a location services (LCS) system, indicated generally by the reference numeral 10, that could be used in the algorithm 1 to enable a user device to be polled by a charging module each time that an action that incurs a charge is made.

The LCS system 10 comprises a mobile station (MS) 12, a base transceiver station (BTS) 14, a base station controller (BSC)/radio network controller (RNC) 15, a mobile switching centre (MSC) 16, a visitor location register (VLR) 18, a gateway mobile location centre (GMLC) 20, a home location register (HLR) 22 , a location services (LCS) client 24 and a serving mobile location centre (SMLC) 25. The SMLC can be connected to a BSC or RNC 15 as shown in Figure 2, but can alternatively reside within a BSC or RNC.

The MS 12 is in two-way communication with the MSC 16 via the BTS 14 and the BSC/RNC 15. The MSC 16 is connected to the VLR 18 and the GMLC 20. The GMLC 20 is also connected to the HLR 22 and the LCS client 24. The BSC/RNC is connected to the SMLC 25.

The VLR 18 is used to store information regarding mobile stations that are visiting the network with which the MSC 16 is associated and the HLR 22 is used to store information regarding the mobile stations subscribing to the particular network.

The GMLC 20 contains the functionality required to support location services (LCS). In use, the LCS client 24 requests the location of the MS 12. The GMLC requests location data from the relevant MSC 16 and the MSC 16 communicates with the MS 12 to obtain the required location data. The location data is then passed from the MSC 16 to the GMLC 20 and on to the LCS client 24. According to the Third Generation Partnership Project (3GPP) location services (LCS) standard, the MSC 16 forwards location requests received from the LCS client 24 to the radio network controller (RNC) 15. The RNC 15 uses the Serving Mobile Location Center (SMLC) 25 to obtain location information. The SMLC 25 can communicate with the MS 12 concerned on various levels, as needed. For example, the SMLC 25 may simply page the MS 12 or send specific location- related messages to the MS to request, for example, GPS location data.

A variety of schemes are known in the art for obtaining location data from the MS 12. For example, in addition to the Third Generation Partnership Project (3GPP) standardised location services (LCS) solution for GSM and UMTS mentioned above, the Open Mobile Alliance (OMA) has a standardised Secure User Plane Location (SUPL) solution for GSM, UMTS and IS-95. Other known schemes for determining the position of a mobile device include global positioning system (GPS) satellite positioning, assisted GPS (A-GPS), time of arrival (TOA) algorithms, observed time difference (E-OTD) algorithms, and cell global identity- timing advance (CGI-TA) methods. Other suitable schemes will be known to those skilled in the art.

A problem with the arrangement described above with reference to Figure 2 is that the quantity of data passing between the LCS client 24, the GMLC 20, the MSC 16 and the MS 12 can be large. Further, many uses of the system 10 will include a large number of MS 12, many of which may be used at the same time, potentially resulting in a very large flow of location data within the system. With large data flows, the impact on a network (for example, in terms of network performance) can be significant. There are costs associated with transferring large quantities of data and there are also costs associated with managing this data flow. The overheads introduced by implementing the algorithm 1 using the system 10 as outlined above have generally been considered to outweigh the potential advantages of providing home zones and other special tariff areas.

A further problem is the need to define the location of a mobile communication device with sufficient accuracy and assurance to determine whether or not the device is within a special tariff area. If a system incorrectly determines that a user is outside of a special tariff area, then the user will be over-charged. If a system incorrectly determines that a user is within a special tariff area, then the user will be under-charged. Both situations are unacceptable, since the first leads to unsatisfied customer and the second leads to loss of revenue for the operator. The difficulties associated with ensuring that location data is sufficiently accurate increases the problems discussed above concerning handling large amounts of location data. Thus, as indicated above, the overheads associated with implementing special tariff areas has generally been considered to outweigh the potential advantages.

The skilled person will recognise that the system 10 has been described above using the terminology of the Global System for Mobile Communications (GSM). Other systems could, of course, be used. One such alternative is the Universal Mobile Telecommunication System (UMTS) network standard. Other network standards are also known that can be used to support location services. As will be known to the skilled person, in UMTS, the terms user equipment (UE) and Node-B are often used instead of mobile station (MS) and base transceiver station (BTS). For the purposes of the present document, those terms should be considered to be interchangeable.

The present invention seeks to address at least some of the problems outlined above.

According to an aspect of the invention, there is provided a method comprising: obtaining (for example, using a controller) passive location data for a mobile communication device (such as the location area code or the cell identity); comparing (for example, using a comparator or some other comparison module) the passive location data with one or more special tariff areas (such as a home zone or an office zone); and determining (for example, using a controller or a charging module) whether or not the mobile communication device is within at least one of said one or more special tariff areas. The passive location data may be obtained from a passive data collector. The method may further comprise providing an output indicating whether or not the mobile communication device is within at least one of said one or more special tariff areas. The method may further comprise providing an output identifying any special tariff area(s) within which the mobile communication device is located.

According to an aspect of the invention, there is provided an apparatus comprising: an input for receiving a request (for example, from a charging module) to determine whether a mobile communication device is within one or more special tariff areas; a controller adapted to obtain passive location data for the mobile communication device; and a comparator for comparing the passive location data with one or more special tariff areas (such as a home zone or an office zone). The passive location data may be obtained from a passive data collector. The apparatus may include an output for indicating whether or not the mobile communication device is within at least one of said one or more special tariff area.

According to an aspect of the invention, there is provided an apparatus comprising: means for obtaining passive location data for a mobile communication device (such as the location area code or the cell identity); means for comparing the passive location data with one or more special tariff areas (such as a home zone or an office zone); and means for determining whether or not the mobile communication device is within at least one of said one or more special tariff areas. The passive location data may be obtained from a passive data collector. The apparatus may comprise means for providing information (such as an indication of whether the mobile communication device is within a special tariff area and/or an indication of which (if any) special tariff area(s) the mobile communication device is located within) to a charging module.

According to an aspect of the invention, there is provided a computer program product comprising: means for obtaining passive location data for a mobile communication device (such as the location area code or the cell identity); means for comparing the passive location data with one or more special tariff areas (such as a home zone or an office zone); and means for determining whether or not the mobile communication device is within at least one of said one or more special tariff areas. The passive location data may be obtained from a passive data collector. The computer program product may comprise means for providing information (such as an indication of whether the mobile communication device is within a special tariff area and/or an indication of which (if any) special tariff area(s) the mobile communication device is located within) to a charging module.

According to an aspect of the invention, there is provided a computer program comprising: code for obtaining passive location data for a mobile communication device (such as the location area code or the cell identity); code for comparing the passive location data with one or more special tariff areas (such as a home zone or an office zone); and code for determining whether or not the mobile communication device is within at least one of said one or more special tariff areas. The passive location data may be obtained from a passive data collector. The computer program may comprise code for providing information (such as an indication of whether the mobile communication device is within a special tariff area and/or an indication of which (if any) special tariff area(s) the mobile communication device is located within) to a charging module. The computer program may be a computer program product comprising a computer-readable medium bearing computer program code embodied therein for use with a computer.

Thus, the present invention provides a lightweight solution to the provisioning of information regarding special tariff areas that seeks to avoid overburdening the system in the way that systems that rely on active location determination can.

In some forms of the invention, passive location data for the mobile communication device is obtained by polling a passive data collector. This may be a straightforward step that simply requests data that has previously been stored by the passive data collector. The storage of data by the passive data collector may be a background process. In such an arrangement, passive location data can be provided on request in a simple manner that does not require significant management of data flow. In some forms of the invention, a request is received from a requesting module, such as a charging module, asking whether the mobile communication device is within one or more of the one or more special tariff areas. An apparatus in accordance with the invention may include an input for receiving such a request. The step of comparing the passive location data with one or more special tariff areas may be carried out in response to receiving the request received from the requesting or charging module. The step of determining whether or not the mobile communication device is within a special tariff area may be carried out in response to receiving the request from the requesting or charging module.

In some forms of the invention, at least some of the passive location data for the mobile communication device may be returned to the requesting or charging module. An apparatus in accordance with the invention may include an output for providing the said data. This data may be used for many purposes. For example, the data may be used to enable the requesting or charging module to determine whether the mobile communication device is within one or more of the one or more special tariff areas.

In some forms of the invention, an indication of whether the mobile communication device is within the special tariff area may be returned to the requesting or charging module. An apparatus in accordance with the invention may include an output for providing the said indication.

In some forms of the invention, an indication of which special tariff area(s) (if any) the mobile communication device is located within may be returned to the requesting or charging module. An apparatus in accordance with the invention may include an output for providing the said indication.

The passive location data for the mobile communication device may be compared with a location of the special tariff area, for example by using a comparator or some other comparing means. In some forms of the invention, the comparison step is carried out by the requesting or charging application. In other forms of the invention, the comparison step is carried out by a home zone middleware module or some other module provided for the purpose. The module for performing the comparison step may be provided as part of a modified gateway mobile location centre (GMLC) that may also include the passive data collector.

In some forms of the invention, it is determined, from the passive location data, whether or not a mobile communication device is a candidate for being within a special tariff area. For example, it may be determined whether or not it is possible, on the basis of the passive location data, that the mobile communication device might be within a special tariff area. In the event that the mobile communication device is deemed to be a candidate for being within a special tariff area, an active location module may be activated in order to determine a location for the mobile communication device. In the event that active location determination is more accurate and/or reliable than passive location determination, the use of active location determination only for mobile communication devices that are candidates for being within a special tariff area combines the advantages of accurate location determination (provided by active location determination) with a reduction in the impact on the overall system (provided by using passive location determination for identifying candidate devices). A module may be provided for determining whether or not the device is a candidate for being within a special tariff area.

In some forms of the invention, in the event that available passive location data (for example, that stored at a passive data collector) is unable to provide an adequate location for the mobile communication device, an active location module is activated to determine a location for the mobile communication device. In such an arrangement, active location determination can be reserved for circumstances where passive location determination is not possible. Alternatively, or in addition, active location determination may be used where passive location data exists, but is deemed inadequate, for example because the data is too old. A module may be provided for determining whether or not the available passive location data is able to provide an adequate location for the mobile communication device.

In some forms of the invention, the step of determining whether or not the mobile communication device is within a special tariff area includes using an active location module if any of the following conditions exist: no passive location data exists for the device, passive location data exists but is deemed to be too old, and passive location data exists and indicates that the mobile communication device is a candidate for being within a special tariff area.

The present invention may further comprise the uploading of passive location data to a passive data collector. The passive location data may be uploaded as a background process, which can reduce the impact of the location data storage procedure on the functionality of the remainder of the system. For example, the uploading process can be designated as a low priority process and can, for example, be delayed in times of high network demand to enable more important data traffic to be transmitted. The passive location data may be uploaded when a specific event occurs, such as when the mobile communication device concerned is used (e.g. a call is made), or when the location of the device changes significantly, or when a predetermined period of time since an upload of data has taken place has expired.

In some forms of the invention, passive location data is filtered. For example, uploaded passive location data may be filtered before being stored at the passive data collector. For example, the passive location data may be filtered on the basis of the terminal identity, so that only data relating to the devices of users registered to use a special tariff area is stored. Alternatively, or in addition, the passive location data may be filtered on the basis of the location of the device; for example, the cell identity of the device may be used.

According to a further aspect of the invention, there is provided a system comprising a first apparatus and a charging application, wherein the first apparatus comprises: an input for receiving a request from the charging module to determine whether a mobile communication device is within one or more special tariff areas; a controller adapted to obtain passive location data for the mobile communication device; and a comparator for comparing the passive location data with one or more special tariff areas (such as a home zone or an office zone). The passive location data may be obtained from a passive data collector. The first apparatus may include an output for indicating to the charging application whether or not the mobile communication device is within at least one of said one or more special tariff areas. The first apparatus may provide location information to the charging application enabling the charging application to determine whether or not the mobile communication device is within at least one of said one or more special tariff area. The first apparatus may be a home zone middleware module. The charging application may calculate an appropriate charge for services used by the mobile communication device.

Exemplary embodiments of the invention are described below, by way of example only, with reference to the following numbered drawings.

Figure 1 is a flow chart demonstrating an algorithm for determining whether a user is within a special tariff area; Figure 2 is a block diagram of a known location services system;

Figure 3 is a block diagram of a system in accordance with an aspect of the present invention;

Figure 4 is a flow chart demonstrating an aspect of the present invention; Figure 5 is a flow chart showing a variant of the algorithm shown in Figure 4; and

Figure 6 is a flow chart demonstrating an aspect of the present invention.

Figure 3 is a block diagram, indicated generally by the reference numeral 30, showing a system in accordance with an aspect of the present invention. The system 30 comprises a mobile communications network 32, a gateway 34 and a charging application 36.

The mobile communications network 32 may be a public land mobile network (PLMN). The network 32 may, for example, include the MS 12, BTS 14,

BSC/RNC 15, MSC 16, VLR 18 and SMLC 25 described above with reference to Figure 2. As shown in Figure 3, the gateway 34 is located between the mobile network 32 and the charging application 36. In use, the gateway 34 is queried by the charging application 36 to obtain location information for a particular MS within the mobile network 32. The charging application then uses this information to determine the appropriate charge for services used by that MS.

The gateway 34 includes a passive data collector (PDC) 38, a GMLC 40 and a home zone middleware (HZMW) module 42. The gateway 34 performs the functionality of the GMLC 20 described above with reference to Figure 2, and also provides additionally functionality as described in detail below. The charging application 36 has an output providing a signal 44 to the HZMW module 42 and the HZMW module has an output providing a signal 46 to the charging application.

The passive data collector (PDC) 38 receives passive location data from subscribers of the mobile network 32. Passive location data can be any available data that has some information regarding the location of a user device. Typically, the passive location data includes a Location Area Code (LAC) and Cell Identity (Cl) of a terminal, but passive location data is not restricted to such data. In one form of the invention, the PDC 38 is updated when the relevant database of the VLR 18 of an implementation of the network 32 is updated.

Passive location data is a term used for data that may be useful for location purposes, but is usually generated for some other reason. Passive location data is often imprecise, giving an indication of general location, rather than an exact location. In many cases, passive location takes the form of network topology information (for example, indicating that a user device is within a particular cell).

Some examples of passive location data include: location update information; routing area information (whilst in a GPRS standby state); serving cell information (where a MS is during a call or sending a short message (SMS) or during a handover); and network measurement report (NMR) information. Passive location data might include an indication of the city or the country in which the user device is located. The passive location data stored at the PDC 38 may be updated when one of a number of events occurs. These events may include one or more of the following:

• The user terminal is active (e.g. making a call, sending an SMS etc.)

• The user terminal moves to a sufficient degree that the location area of the terminal changes

• An update period has elapsed since the location was last updated.

The update of the PDC 38 is a background process and is used to provide the

PDC 38 with location data regarding the users of the mobile network 32. This data is used by the HZMW module 42 to determine whether users are within a special tariff area, as described below with reference to Figure 4.

The charging application 36 calculates the appropriate charge for a service being used by a user of the mobile network 32. When a service (such as a call) is initiated, the charging application 36 sends a request (signal 44) to the gateway 34 asking whether the relevant user device is within a special tariff area, such as a home zone. The charging application 36 receives a response (signal 46) from the gateway 34. The format of the request to and response from the gateway 34 can take many different formats. Exemplary formats include HTTP, XML and SOAP. The skilled person will be aware of many other formats that could be used.

By way of example, the signal 44 may take the form of a zone check request and the signal 46 may take the form of a zone check response, as follows:

Zone check request [HTTP/XML (Request ID, MSISDN, zone definition)] Zone check response [HTTP/XML (Request ID, indication/location)]

Where "Request ID" identifies a particular request, MSISDN (or Mobile Station International Subscriber Directory Number), identifies a particular MS 12, "zone definition" identifies a particular special tariff area and the zone check response provides either an indication of whether or not the identified MS is within the identified special tariff area or, alternatively, provides data concerning the location of the identified MS.

In an alternative form, the request 44 and response 46 are split into two requests and two responses, as follows:

Zone check request [HTTP/XML (Request ID, zone definition)] Zone check response [HTTP/XML (Request ID, zone identity)] Zone check request [HTTP/XML (Request ID, MSISDN, zone identity)] Zone check response [HTTP/XML (Request ID, indication/location)]

Once the charging application 36 knows the appropriate tariff to use, a charge for a service used by a user device can be calculated in a manner well known in the art. The charges made will be dependent on the operator and on local markets. By way of example, assume that the cost of making a call using a fixed line in a particular area is 1 unit per minute and the cost of making a call using a mobile communication device is 5 units per minute. In such a scenario, the mobile operator may reduce the charge for using the mobile communication device to 1 unit per minute for call made within the home zone of the user.

Figure 4 is a flow chart of an algorithm, indicated generally by the reference numeral 50, demonstrating part of the functionality of the HZMW module 42.

The algorithm 50 starts at step 52, where the HZMW module monitors the signal 44 received from the charging application 36 to determine whether a home zone (HZ) request has been issued by the charging application. The step 52 is repeated until a HZ request is received. The step 52 is shown as a loop, but it could, of course, be implemented as an interrupt, with the receipt of a HZ request being used to trigger the start of the remainder of the algorithm 50.

On receipt of a HZ request, the algorithm 50 moves to step 54, where the HZMW module polls the PDC 38 to obtain passive location data for the user device concerned (by sending a request on signal 44). The polling of the PDC may be straightforward. Since the PDC is being updated with location information as a background process, the passive location data is stored at the PDC and can be provided on request.

The algorithm then moves to step 56, where the HZMW module 42 uses the location data obtained in step 54 to determine the location of the user device. This may be done, for example, using a simple look-up table, where for each possible response from the PDC 38 (such as cell identity) there is a corresponding longitude and latitude. The longitude and latitude figures could, for example, be the co-ordinates of a base station antenna or the co-ordinates of the centre point of the coverage area of the cell.

Next, at step 58, the HZMW module 42 compares the location of the user device with the defined home zone area and determines whether or not the user device is within the home zone. If the user device is within the home zone, the algorithm moves to step 60 where the message "Within HZ" is returned to the charging application as signal 46. Otherwise the algorithm moves to step 62 where the message "Outside HZ" is returned to the charging application as signal 46. The algorithm then returns to step 52 from either step 60 or step 62.

Of course, the algorithm 50 can readily be modified to determine whether the user device is within any specified special tariff area (i.e. it is not limited to use with home zones).

In the algorithm 50, it is assumed that the PDC 38 is able to provide the required passive location data. This might not always be the case. For example, the passive location data may be deemed to be too old. This might occur, for example, if the mobile communication device concerned is switched on but not being actively used, or is switched off. Figure 5 shows an algorithm, indicated generally by the reference numeral 70, showing a variant of the algorithm 50.

The algorithm 70 starts when a home zone (HZ) request is received (i.e. when the step 52 returns a "Yes"). The algorithm 70 starts with the PDC 38 being polled in step 72 (in the same manner as in the step 54 discussed above). Next, in step 74, it is determined whether appropriate passive location data exists for the user device concerned. If suitable data exits, then the algorithm moves to step 76, where the location of the user device is determined (as in step 56 of the algorithm 50). With the location determined, the remainder of the steps of the algorithm 50 (from step 58 onwards) can be completed.

If it is determined in the step 74 that suitable passive location data is not available for the user device, then the algorithm 70 moves to step 78, where an active location determination is performed, in a similar manner to the location determination discussed above with reference to Figure 2. Again, once the location of the user device has been determined, the remainder of the steps of the algorithm 50 (from step 58 onwards) can be completed.

A potential problem with the use of passive location data for determining whether or not a user is within a special tariff area is that it may not be possible to identify the location of the user with sufficient precision using passive location data alone. Figure 6 shows an algorithm, indicated generally by the reference numeral 80, intended to address this issue.

The algorithm 80 starts following the receipt of a home zone (HZ) request from the charging application 36 (i.e. it is assumed that the step 52 has returned a "Yes" response).

The algorithm 80 starts at step 82, where the PDC 38 is polled in order to obtain passive location data for the relevant user device. The passive location data is used in step 84 to determine whether or not the user device could potentially be within a special tariff area. For example, the passive location data may be used to identify whether the user device is within a given area (such as a cell, or a city) that is larger than a particular special tariff area. For example, the special tariff area might be a particular home zone and the passive location data may only be able to specify the location of the user device to within an accuracy of a few hundred metres. If the passive location suggests that the user device is several miles away from the home zone, then the device is clearly outside the home zone. However, if the passive location suggests that the user device is within the home zone, the lack of accuracy of the location data may mean that it is not possible to be certain whether or not the user device is within the home zone.

In the algorithm 80, if the passive location data indicates that the user cannot be within a special tariff area, then the algorithm 80 moves to step 92, where a message "Outside HZ" is returned to the charging application 36. If the passive location data indicates that the user device could potentially be within a special tariff area, then the algorithm 80 moves to step 86 where an active location determination is conducted (in a similar manner to the location determination discussed with reference to Figure 2) to determine the location of the user device more precisely. Following the active location determination, a final determination is made regarding whether or not the user device is within the special tariff area (step 88). If the user device is within the special tariff area, the algorithm moves to step 90 where a message "Within HZ" is returned to the charging application 36. If the user device is outside the special tariff area, then the algorithm moves to step 92 where a message "Outside HZ" is returned to the charging application 36.

The features of the algorithms 70 and 80 may be combined. For example, an active location determination may be conducted if either suitable data is not available from the PDC (implementing step 78 of the algorithm 70) or if the passive data suggests that the user device might be within a special tariff area (implementing step 86 of the algorithm, 80). In such a combined algorithm, no active search would be conducted if suitable passive location data is available for the user device and that passive location data shows that the user device is outside the range of any special tariff area.

The embodiments of the invention described above have generally provided an output indicating whether a particular mobile communication device is within or outside a home zone. This invention is not so limited. As indicated elsewhere, the invention is not limited to home zones; other special tariff areas might be indicated. Further, the invention is not limited to providing a within/without output. For example, the invention may provide an output identifying which special tariff area(s) (if any) a particular mobile communication device is currently located within. In an alternative embodiment of the invention, the gateway 34 returns location data to the charging module 36 and the charging module determines whether or not the MS 12 is within a special tariff area.

In some forms of the invention, the PDC 38 filters data received from the mobile network 32 and only stores data of relevance to the HZMW module 42 and the charging application 36. For example, the PDC may filter the incoming data on the basis of the terminal identity, so that only data relating to the device of users registered to use a special tariff area is stored. Alternatively, or in addition, the PDC 38 may filter the incoming data on the basis of cell identity. For example, the PDC 38 may only store data relating to devices that are physically close to a special tariff area. The filtering may be carried out within the PDC itself, or by a separate filtering module. Filtering can be simple, for example based on a list of cell IDs or location area IDs that are stored. Similarly, filtering could be based on MS IDs or ranges. A combination of location-based and MS-based filtering could also be used (either as an AND combination, or as an OR combination). By way of example, the mobile network 32 may include a large number of MS 12, of which only, say, two have special tariff areas defined. The PDC 38 may receive passive location data for all of the mobile communication devices in the network 32, but may include a filter such that only passive location data concerning the two devices having special tariff areas defined are stored. Further, the passive location data for those two devices may only be updated if the device concerned is near, or within, a defined special tariff area, or if the device either moves into, or out of, a special tariff area.

The embodiments of the invention described above are illustrative rather than restrictive. It will be apparent to those skilled in the art that the above devices and methods may incorporate a number of modifications without departing from the general scope of the invention. It is intended to include all such modifications within the scope of the invention insofar as they fall within the scope of the appended claims.

Claims

CLAIMS:

1 . A method comprising: obtaining passive location data for a mobile communication device; comparing the passive location data with one or more special tariff areas; and determining whether or not the mobile communication device is within at least one of said one or more special tariff areas.

2. A method as claimed in claim 1 , further comprising receiving a request from a requesting module to determine whether the mobile communication device is within one or more of the one or more special tariff areas.

3. A method as claimed in claim 2, further comprising returning at least some of the passive location data for the mobile communication device to the requesting module.

4. A method as claimed in claim 2 or claim 3, further comprising returning an indication to the requesting module of whether the mobile communication device is within said one or more of the one or more special tariff areas.

5. A method as claimed in any preceding claim, wherein in the event that the mobile communication device is deemed to be a candidate for being within a special tariff area, the step of determining whether or not the mobile communication device is within at least one of said one or more special tariff areas includes using an active location module to determine a location for the mobile communication device.

6. A method as claimed in any preceding claim, wherein, in the event that available passive location data is unable to provide an adequate location for the mobile communication device, the step of determining whether or not the mobile communication device is within at least one of said one or more special tariff areas includes using an active location module to determine a location for the mobile communication device.

7. A method as claimed in any preceding claim, further comprising receiving passive location data for one or more mobile communication devices from a mobile communication network as a background process.

8. A method as claimed in claim 7, further comprising filtering said received passive location data and storing said filtered data.

9. A method as claimed in claim 8, wherein filtering said received passive location data includes filtering the data on the basis of an identity of the mobile communication device.

10. A method as claimed in claim 8 or claim 9, wherein filtering said received passive location data includes filtering the data on the basis of a location of the mobile communication device.

1 1 . An apparatus comprising: an input for receiving a request to determine whether a mobile communication device is within one or more special tariff areas; a controller adapted to obtain passive location data for the mobile communication device; and a comparator for comparing the passive location data with one or more special tariff areas.

12. An apparatus as claimed in claim 1 1 , further comprising an output for providing an indication regarding whether or not the mobile communication device is within at least one of said one or more special tariff areas.

13. An apparatus as claimed in claim 1 1 or claim 12, wherein the passive location data is obtained from a passive data collector.

14. An apparatus as claimed in claim 13, further comprising the passive data collector.

15. An apparatus as claimed in any one of claims 1 1 to 14, further comprising a filter for filtering uploaded passive location data.

16. An apparatus as claimed in any one of claims 1 1 to 15, further comprising a charging module.

17. A computer program product comprising: means for obtaining passive location data for a mobile communication device; means for comparing the passive location data with one or more special tariff areas; and means for determining whether or not the mobile communication device is within at least one of said one or more special tariff areas.