Abstract:
Methods and arrangements are provided for use in a mobile communications network to determine an appropriate tariff for a mobile station accessing the capabilities of a mobile communications network having a coverage area that extends over a plurality of time-zone, borders, and/or other cost/service-sensitive regions. A time stamp is used, which includes an offset value associated with the location of the mobile station accessing the mobile communication services, to more precisely and efficiently determine an appropriate tariff to be charged, and/or service to be rendered to the subscriber associated with the mobile station. The methods and arrangements are particularly useful in mobile communication networks having satellite nodes.

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field of the Invention 
     The present invention relates to mobile communications, and, more particularly, to methods and arrangements for efficiently determining the proper time and tariff associated with a mobile station operating in a mobile communications network that is capable of providing communication services to one or more areas that are located within a plurality of different time-zones. 
     2. Description of Related Art 
     Mobile communications systems, such as, for example, a Global System for Mobile (GSM) communications system, are typically designed to provide communication services to subscribers located a fairly large coverage region, that has been subdivided into a plurality of cells. Typically, these cells are located within certain distinct and known time-zones, and the services associated with the mobile communication system are tied to the time of day within the cell from which the subscriber places the call. 
     Often, the mobile communication network informs the mobile station of the tariffs or other charges associated with the requested/continuing call. In this manner, the subscriber is made aware of the costs associated with the call. In the past this additional feature has been fairly easy to provide, because the mobile switching center is usually located nearby the mobile station, and typically within the same time-zone. Additional tariff related features/issues, concern borders, for example between countries, etc. Here, there can also be a need to make further adjustments to the estimated tariff information provided to the mobile station for display to the subscriber. As is often the problem, the estimated tariff provided to the subscriber in near real-time can differ significantly from the actual post-processed tariff mailed at a later time to the subscriber. One reason for this is that the time associated with the location of the mobile station is not always immediately determinable for use in the estimate calculation. 
     Recent developments have brought about a more expansive mobile communications system capability. In particular, satellites are being introduced to provide even wider area coverage for mobile stations. Accordingly, the coverage areas provided by a high orbit satellite (e.g., geosynchronous orbit) can be so large that multiple time-zones are crossed, and/or multiple countries/region borders are included for coverage. 
     Consequently, there is a need for improved methods and arrangements that can be employed to determine an accurate tariff based on the location of the mobile station. Preferably, the estimated tariff and post processed tariff will substantially match one another. 
     Another advantage of the instant invention is in pre-paid phone services where the timely calculation of tariff is critical. 
     SUMMARY OF THE INVENTION 
     The various methods and arrangements in accordance with the present invention can be easily employed to determine an accurate tariff based on the location of the mobile station, where the estimated tariff and post processed tariff substantially match one another. 
     The above needs and others are met by a method for use in mobile telecommunication systems. The method includes the steps of establishing a reference time, determining an offset for a mobile station with respect to the reference time, and determining a cost associated with a call connection to the mobile station based on a tariff associated with a local time that is determined using the reference time and the offset time. For example, in certain embodiments, the reference time is Greenwich Mean Time (GMT) or Global Positioning Satellite (GPS) time, and the offset is determined by the mobile station based on its current geographical location with respect to the reference time. In other embodiments, the offset is provided to a post processing unit, after having passed through a satellite, a base station and/or a mobile switching center. 
     An arrangement is also provided, which includes a mobile station that is configured to determine a offset with respect to a current determined location and a reference time. The mobile station transmits the offset to at least one satellite, which in-turn provides the offset to at least one ground node that is configured to determine a cost associated with a call connection to the mobile station based on a tariff associated with a local time that is determined using the reference time and the offset time. 
     Consequently, the mobile communication system can be provided with the capability to determine the costs associated with a call placed by a subscriber more quickly and accurately. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete understanding of the various methods and arrangements of the present invention may be obtained by reference to the following Detailed Description when taken in conjunction with the accompanying Drawings wherein: 
     FIG. 1 is a block diagram depicting an exemplary arrangement of a mobile communications network in accordance with certain embodiments of the present invention; 
     FIG. 2 is a block diagram of a portion of the mobile communications network illustrated in FIG. 1 in accordance with certain embodiments of the present invention; and 
     FIG. 3 is a flow-chart depicting an exemplary process for generating a bill based on a time offset within a mobile communication network in accordance with certain embodiments of the present invention. 
    
    
     DETAILED DESCRIPTION 
     The numerous innovative teachings of the present application will be described with particular reference to the presently preferred exemplary embodiments. However, it should be understood that this class of embodiments provides only a few examples of the many advantageous uses of the innovative teachings herein. In general, statements made in the specification of the present application do not necessarily delimit any of the various claimed inventions. Moreover, some statements may apply to some inventive features but not to others. 
     FIG. 1 is a block diagram depicting an exemplary arrangement for a mobile communications network  10 . Mobile communications network  10  is configured to provide coverage over a significantly large region  12  that includes, for example, three distinct time-zones, namely time zone A, time zone B and time zone C, respectively designated by the reference identifiers  14 A,  14 B and  14 C. These time zones could further represent different tariff zones, countries, etc. A satellite  16  is provided, preferably in a geosynchronous orbit over region  12  and configured to provided uplink and downlink communication services to mobile stations located within the coverage area of mobile communications network  10 . By way of example, satellite  16  can provide spot beam coverage to selected portions or cells within each of the three time zones  14 A-C. Thus, as shown, a spot beam defined as cell  28 A is depicted in time zone A ( 14 A). Within cell  28 A there is a mobile station (MS)  26 A that is configured to communicate with satellite  16 . Similarly, there is another spot beam defined as cell  28 C depicted in time zone C ( 14 C). Here, within cell  28 C there is another mobile station (MS)  26 C that is also configured to communicate with satellite  16 . Finally, within time zone B ( 14 B), there is a satellite base station subsystem (BSS)  18  that is configured to send uplink signals to satellite  16  and downlink signals from satellite  16 . Satellite BSS  18  is further connected to a mobile switching center (MSC)  20 , which is configured to complete call connections through one or more external networks, generally designated by the reference numeral  22 , with at least one telecommunications terminal (TT)  24 . 
     There is a need to differentiate the local times for calls placed in these various time zone, particularly, when tariffs and/or features correspond to the location and/or time during which access to the communications services is made. 
     Thus, for example, MS  26 A may be charged at a premium rate for calls make during a prescribed time, while further away, the rates for MS  26 C are discounted because of the local time difference. 
     BSS  18  is connected to a mobile switching center (MSC)  20 . MSC  20  can be configured to provide connectivity through at least one fixed network  22 , such as, for example, a public switched telephone network (PSTN), to a remote telecommunications terminal (TT)  24 . In this manner calls can be connected between MS  26 A,  26 B and/or TT  24 , using satellite  16 , BSS  18 , MSC  20  and network  22 . 
     As graphically depicted in FIG. 1, satellite  16  utilizes spot beam technologies to differentiate between selected regions or cells. 
     With reference now to FIG. 2, there is illustrated is a block diagram depicting a portion of a mobile communications network that is concerned with determining the cost and/or services associated with a mobile station operating in the coverage areas in FIG.  1 . Here, BSS  18  is configured to receive signals and data from satellite  16 . For example, in certain embodiments, BSS  18  receives an offset  32  from MS  26 A via satellite  16 . Offset  32  identifies how far away, physically, the MS is from a particular reference that is used to calculate the costs and services available to the subscriber as currently located. Thus, for example, offset  32  can include a time value that is associated with the difference in time from the time zone in which the MS is currently located in and the reference time. In certain cases, therefore, the offset from MS  26 A might be −1, which indicates that time zone  14 A is one hour slower than the reference time that happens to be that of time zone  14 B. In other examples, offset  32  reflects the difference between a universal time standard, such as, for example, GMT or GPS time. 
     The received offset  32  is then forwarded to MSC  20 , which in turn provides offset  32  or a portion thereof to a post processing unit  30 . Post processing unit  30  is configured to generate a bill  34  or similar invoice for the communication services provided, for example, based on the offset, the call duration, the selected features, the type of call, the called party, the time of day/night, the day of the week, certain taxes, the bandwidth required, etc. 
     In accordance with still other embodiments of the present invention, MS  26 A, for example, need not provide offset  32  to BSS  18 , but can rather provide a location identifier to BSS  18 . BSS  18  can then generate an offset  32  using the MS location identifier to determine the appropriate zone form the MS. Thus, BSS  18  can generate and provide offset  32  to MSC  20 . 
     Similarly, in accordance with still further embodiments of the present invention, MS  26 A, for example, need not provide offset  32  to BSS  18 , but can rather provide a location identifier to BSS  18 . BSS  18  can pass this location identification on to MSC  20 . MSC  20  can then generate an offset  32  using the MS location identifier to determine the appropriate zone form the MS. Thus, MSC  20  can generate and provide offset  32  to post processing unit  30 . 
     Location identifier information can be determined by MS  26 A using several known techniques, including, for example, GPS positioning data, beacon triangulation/arcuation gathered data, etc. Furthermore, a more granular locations identifier can be determined by identifying the slot beam or cell associated with satellite  16 . 
     With this in mind, shown in FIG. 3 is a flow chart depicting a process  100  for using an offset value in a mobile communications network to determine applicable tariffs and/or services to be provided to a MS. 
     In step  102 , a reference time is determined or otherwise established. The reference time can be a global standard time, or a time associated with the time zone encompassing BSS  18 , MSC  20 , etc. In step  104 , an offset  32  is determined for the MS based on its location with respect to the reference time established in step  102 . Next, in step  106 , the offset is provided to a post processing capability  30 . In step  108 , post processing capability  30  determines and generates a bill associated with the communication service provided to the subscriber of the MS based on the time zone or location of the MS in accordance with the referenced time and offset  32 . In accordance with certain aspects of the present invention, the above described offset evaluation process tends to make the estimated costs displayed at the MS, substantially match the actual billed costs as determined subsequently by post processor unit  30 . 
     As discussed, the principles of the present invention may also be used in pre-paid phone services where the timely calculation of a tariff is important. As is understood in the art, this pre-paid service may be Intelligent Network-based or non-IN based. 
     The previous description is of preferred embodiments for implementing the invention, and the scope of the invention should not necessarily be limited by this description. The scope of the present invention is instead defined by the following claims.