System for providing alert-based services to mobile stations in a wireless communications network

• US 20050043037A1
• Filed: 07/16/2002
• Published: 02/24/2005
• Est. Priority Date: 07/16/2001
• Status: Active Grant

• Current Assignee: Smith Micro Software Incorporated
• Original Assignee: Wavemarket Incorporated (Gen Digital Inc.)
• Inventors: Roumeliotis, Tasso, Hotes, Scott Allen, Susal, Joel A., Klein, Philip Nathan, Ioppe, Igor V.
• Granted Patent: US 7,643,834 B2
• Time in Patent Office: Days
• US Class Current: 455/456.100
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 64/006 with additional information processing, e.g. for direction or speed determination
• CPC Class Codes: H04W 8/08 Mobility data transfer
• CPC Class Codes: H04W 8/10 between location register and external networks
• CPC Class Codes: H04W 88/18 Service support devices; Network management devices

Abstract

System for providing alert-based communication services for which corresponding alert conditions to be met by mobile stations are defined. The system includes an alert engine capable of firing alerts associated with the alert-based communication services if location data regarding the mobile stations is indicative of the mobile stations meeting the alert conditions corresponding to the alert-based communication services. A requirements engine is provided for determining an expected earliest future time at which at least one alert condition is capable of being met by a particular mobile station and outputting a data element indicative of a requirement to obtain updated location data about the particular mobile station in advance of the expected earliest future time. Also provided is a scheduler for receiving expiry times data indicative of a plurality of expiry times relating to respective location requests, processing the expiry times data for determining an order for servicing the location requests by positioning determining equipment (PDE) at least in part on a basis on the expiry times of the location requests and an output for interfacing with the PDE, allowing it to service the location requests according to the order determined.

Claims

1. Computer-readable media tangibly embodying a program of instructions executable by a computing device to implement a method, the computing device being capable of interfacing with a communications network adapted to provide alert-based services for which corresponding alert conditions to be met by mobile stations are defined, the method comprising:

determining an expected earliest future time at which at least one alert condition is capable of being met by a particular mobile station; and

outputting a data element indicative of a requirement to obtain updated location data about the particular mobile station in advance of the expected earliest future time.

2. Computer-readable media as defined in claim 1, wherein determining the expected earliest future time includes:

estimating a minimum travel time between a last known location of the particular mobile station and a target location associated with the at least one alert condition.

3. Computer-readable media as defined in claim 2, wherein estimating a minimum travel time between the last known location of the particular mobile station and the target location includes:

determining a distance between the last known location of the particular mobile station and the target location;

determining a speed of the particular mobile station;

computing the quotient of the distance and the speed to obtain an estimated minimum travel time between the last known location of the particular mobile station and the target location.

4. Computer-readable media as defined in claim 3, wherein the speed is an instantaneous speed.

5. Computer-readable media as defined in claim 3, wherein the speed is an average speed within an interval of time.

6. Computer-readable media as defined in claim 3, wherein the speed is the greater of an instantaneous speed and an average speed within an interval of time.

7. Computer-readable media as defined in claim 2, wherein estimating a minimum travel time between the last known location of the particular mobile station and the target location includes:

determining the shortest path from the last known location of the particular mobile station to the target location via a set of existing roads; and

determining the least amount of time required to travel the shortest path.

8. Computer-readable media as defined in claim 1, the method further including:

outputting a second data element indicative of a requirement to obtain updated location data about the particular mobile station dating back no later than the current time.

9. Computer-readable media as defined in claim 1, the method further comprising:

outputting a second data element indicative of a requirement to obtain updated location data about the particular mobile station dating back no later than a predetermined time in the past.

10. Computer-readable media as defined in claim 1, the method further comprising:

outputting a second data element indicative of a requirement to obtain updated location data about the particular mobile station no earlier than a predetermined time in the future.

11. Computer-readable media as defined in claim 1, the method further comprising:

receiving location data about the particular mobile station;

wherein the steps of determining and outputting are executed after executing the step of receiving.

12. Computer-readable media as defined in claim 11, wherein the method further comprises:

repeatedly executing the steps of receiving, determining and outputting.

13. Computer-readable media as defined in claim 1, wherein determining an expected earliest future time at which at least one alert condition is capable of being met by the particular mobile station includes determining an expected earliest future time at which any of a plurality of alert conditions is capable of being met by the particular mobile station.

14. Computer-readable media as defined in claim 1, wherein determining an expected earliest future time includes:

estimating a minimum travel time between a last known location of the particular mobile station and the closest amongst a plurality of target locations associated with a plurality of alert conditions.

15. Computer-readable media as defined in claim 1, wherein determining the expected earliest future time includes:

for the alert condition for which the expected earliest future time was minimum, finding a new expected earliest future time;

for all other alert conditions, if the earliest expected future time for that alert condition is before the new expected earliest future time, computing a second new expected earliest future time and setting the new expected earliest future time equal to the least of the new expected earliest future time and the second new expected earliest future time.

16. A method for use in a communications network adapted to provide alert-based services defined for a plurality of mobile stations and a variety of alert conditions, comprising:

determining an expected earliest future time at which at least one alert condition is capable of being met by a particular mobile station; and

outputting a data element indicative of a requirement to obtain updated location data about the particular mobile station in advance of the expected earliest future time.

17. A system for use in a communications network adapted to provide alert-based services defined for a plurality of mobile stations and a variety of alert conditions, comprising:

means for determining an expected earliest future time at which at least one alert condition is capable of being met by a particular mobile station; and

means for outputting a data element indicative of a requirement to obtain updated location data about the particular mobile station in advance of the expected earliest future time.

18. A computer readable storage medium containing a program element for execution by a computing device to implement a method in a communications network adapted to provide alert-based services defined for a plurality of mobile stations and a variety of alert conditions, the program element including:

program code means for determining an expected earliest future time at which at least one alert condition is capable of being met by a particular mobile station; and

program code means for outputting a data element indicative of a requirement to obtain updated location data about the particular mobile station in advance of the expected earliest future time.

19. A data processing device for use in a communications network adapted to provide alert-based services for which corresponding alert conditions to be met by mobile stations are defined, comprising:

an input capable of receiving updated location data about the mobile stations; and

a processing unit connected to the input, said processing unit being capable of;

determining, on the basis of the updated location data about a particular mobile station, for which alert-based services, if any, at least one corresponding alert condition is met by the particular mobile station; and

generating a trigger to fire of an alert associated with each alert-based service for which at least one corresponding alert condition has been met by the mobile station.

20. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being located within a predetermined maximum distance from a target location at a predetermined future time.

21. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being located within a predetermined maximum distance from a target location during a predetermined time range.

22. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station having entered a predetermined target geographic area.

23. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station having exited a predetermined target geographic area.

24. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being located within a predetermined target geographic area at a predetermined time.

25. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being located outside a predetermined target geographic area at a predetermined time.

26. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being located within a predetermined target geographic area for a predetermined duration.

27. A data processing device as defined in claim 26, wherein the predetermined duration is defined as a predetermined number of consecutive times updated location data is received at the input.

28. A data processing device as defined in claim 26, wherein the predetermined duration is defined as a predetermined length of time.

29. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being located within one of a plurality of increasingly peripheral target geographic areas relative to a central target location for a corresponding predetermined duration.

30. A system as defined in claim 29, wherein the predetermined duration corresponding to a peripheral target geographic area is directly related to the degree to which that peripheral target geographic area is peripheral relative to the central target location.

31. A system as defined in claim 30, wherein the predetermined duration corresponding to a peripheral target geographic area is defined as a predetermined number of consecutive times the updated location data is indicative of the mobile station being in that peripheral target geographic area.

32. A system as defined in claim 30, wherein the predetermined duration corresponding to a peripheral target geographic area is defined as a predetermined length of time.

33. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being headed towards a particular direction or location.

34. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being headed away from a particular direction or location.

35. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being headed towards an area congested with traffic.

36. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being located in an area with traffic congestion.

37. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being located on a congested road.

38. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station being headed towards a congested portion of a pre-defined travel route.

39. A data processing device as defined in claim 19, wherein firing of an alert associated with at least one alert-based service is triggered only if the particular mobile station is a member of a selected group of mobile stations.

40. A data processing device as defined in claim 19, wherein the selected group of mobile stations includes a group of mobile stations associated with users sharing a predefined set of at least one common demographic characteristic.

41. A data processing device as defined in claim 19, wherein he selected group of mobile stations includes a group of mobile stations subscribed to a common alert-based service.

42. A data processing device as defined in claim 19, wherein the selected group of mobile stations includes a group of mobile stations associated with users having a common behavioural characteristic.

43. A data processing device as defined in claim 19, wherein firing of an alert associated with at least one alert-based service is conditional upon an alert associated with the at least one alert-based service not having been fired during a predetermined length of time.

44. A data processing device as defined in claim 19, wherein generating a trigger to fire an alert associated with at least one of the alert-based services is conditional upon the current time falling within a predetermined range.

45. A data processing device as defined in claim 19, wherein the alert condition corresponding to at least one alert-based service is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station having a speed outside a predetermined range.

46. A data processing device as defined in claim 19, further comprising a primary memory and a secondary memory, the processing unit further being capable of:

maintaining a set of data structures in the secondary memory, each set of data structures being associated with a time interval, wherein each data structure in a particular set of data structures contains information relevant to a respective subset of alert conditions that require a current time to be in the time interval associated with that set of data structures;

if the primary memory does not contain the set of data structures associated with the time interval containing the current time, overwriting the content of the primary memory with the set of data structures associated with the time interval containing the current time;

wherein the step of determining is effected on the basis of the alert conditions limited to those alert conditions belonging to the subset of alert conditions for which relevant information is contained in the set of data structures associated with the time interval containing the current time.

47. A data processing device as defined in claim 46, wherein each alert condition is considered as having been met by a particular mobile station if the updated location data about the particular mobile station is indicative of the particular mobile station having entered a corresponding alert region, wherein each data structure in each set of data structures includes data indicative of the closest alert region to different locations in the network.

48. A data processing device as defined in claim 47, wherein each data structure in each set of data structures is created by:

dividing the network into nodes;

computing for each node the nearest alert region; and

merging together into cells, those nodes having the same nearest alert region.

49. A data processing device as defined in claim 48, the processing unit being further capable of smoothening out boundaries of the cells resulting from the merge of two or more nodes.

50. A data processing device as defined in claim 49, wherein computing for each node the nearest alert region includes computing a set of Voronoi regions for the nodes.

51. A data processing device as defined in claim 50, wherein the processing unit is further capable of responding to the appearance of a new alert region by:

a) finding the set of nodes for which the new alert region is closer than the nearest alert region previously associated with the node in question; and

b) creating at least one polygon enclosing only the set of nodes found in a).

52. A method for use in a communications network adapted to provide alert-based services for which corresponding alert conditions to be met by mobile stations are defined, comprising:

receiving updated location data about the mobile stations;

determining, on the basis of the updated location data about a particular mobile station, for which alert-based services, if any, at least one corresponding alert condition is met by the particular mobile station; and

generating a trigger to fire an alert associated with each alert-based service for which at least one corresponding alert condition has been met by the mobile station.

53. A system for use in a communications network adapted to provide alert-based services for which corresponding alert conditions to be met by mobile stations are defined, comprising:

means for receiving updated location data about the mobile stations;

means for determining, on the basis of the updated location data about a particular mobile station, for which alert-based services, if any, at least one corresponding alert condition is met by the particular mobile station; and

means for generating a trigger to fire an alert associated with each alert-based service for which at least one corresponding alert condition has been met by the mobile station.

54. Computer-readable media tangibly embodying a program of instructions executable by a computing device to implement a method in a communications network adapted to provide alert-based services for which corresponding alert conditions to be met by mobile stations are defined, the method comprising:

receiving updated location data about the mobile stations;

determining, on the basis of the updated location data about a particular mobile station, for which alert-based services, if any, at least one corresponding alert condition is met by the particular mobile station; and

generating a trigger to fire an alert associated with each alert-based service for which at least one corresponding alert condition has been met by the mobile station.

55. A system for providing alert-based communication services for which corresponding alert conditions to be met by mobile stations are defined, comprising:

an alert engine capable of firing alerts associated with the alert-based communication services if location data regarding the mobile stations is indicative of the mobile stations meeting the alert conditions corresponding to the alert-based communication services.

56. A system as defined in claim 55, further comprising:

a requirements engine capable of specifying time conditions to be satisfied by the receipt of updated location data regarding the mobile stations; and

a scheduler capable of ensuring that the receipt of the updated location data regarding the mobile stations satisfies the time conditions.

57. A system as defined in claim 56, wherein the alert engine is adapted to verify whether a particular alert condition is met by a particular mobile station upon receipt of the updated location data regarding the particular mobile station.

58. A system as defined in claim 57, wherein the alert engine is adapted to verify whether a particular alert condition is met by a particular mobile station upon receipt of the updated location data and only upon satisfaction of the time condition to be satisfied by the receipt of the updated location data regarding the particular mobile station.

59. A method of accessing a data structure for obtaining an earliest expected travel time between a current location and a plurality of alert regions, the data structure containing data regarding a subdivision of a network into cells for which a respective alert region is the nearest to all points in the cell, the method comprising:

(a) using a point-location data structure to determine which cell contains the current location;

(b) using the table to determine the alert region associated with the cell found in step (a); and

(c) using a cost function to determine the travel time from the current location to the alert region found in step (b).

60. An apparatus for scheduling servicing of location requests by a PDE, comprising:

a) an input for receiving expiry times data indicative of a plurality of expiry times relating to respective location requests;

b) a scheduler processing the expiry times data for determining an order for servicing the location requests by the PDE at least in part on a basis on the expiry times of the location requests;

c) an output for interfacing with the PDE allowing the PDE to service the location requests according to the order determined by said scheduler.

61. An apparatus as defined in claim 60, wherein said scheduler includes a storage medium defining a sequence of slots for holding data elements according to the order for servicing the location requests by the PDE.

62. An apparatus as defined in claim 61, wherein each data element in said storage medium is associated to a location request.

63. An apparatus as defined in claim 61, wherein said scheduler is operative to re-compute the order of the data elements in said storage medium when new expiry times data associated with a new location request is received at said input.

64. An apparatus as defined in claim 63, wherein each slot in said sequence of slots corresponds to a point in time at which the position determination equipment is expected to service the location request of a data element stored in the slot.

65. An apparatus as defined in claim 64, wherein the re-computation includes for a new location request identifying a slot in said sequence of slots that corresponds to a point in time for servicing the new location request that is within the expiry time of the new location request.

66. An apparatus as defined in claim 65, wherein the re-computation includes identifying a slot in said sequence of slots that corresponds to a latest point in time for servicing the new location request, without exceeding the expiry time of the location request.

67. An apparatus as defined in claim 66, wherein if the slot that corresponds to the latest point in time for servicing the new location request is vacant, said scheduler is operative for storing a data element associated to the new location request in the slot that corresponds to the latest point in time.

68. An apparatus as defined in claim 67, wherein if the slot that corresponds to the latest point in time for servicing the new location request is occupied by a data element associated with a prior location request, then said scheduler is operative for:

a) displacing the data element associated with the prior location request to a slot corresponding to an earlier point in time for servicing the prior location request to vacate the slot containing the data element associated with the prior location request;

b) inserting the data element associated with the new location request in the vacated slot.

69. An apparatus as defined in claim 61, wherein the data elements are arranged according to a search tree.

70. An apparatus as defined in claim 69, wherein each data element is associated to a location request and each data element is represented by a node in said search tree.

71. An apparatus as defined in claim 70, wherein the nodes of said search tree are ordered according to the expiry times of the respective location requests.

72. An apparatus as defined in claim 71, wherein each data element includes a first label containing information about a number of descendants of the node associated with the data element.

73. An apparatus as defined in claim 72, wherein each data element includes a second label containing information identifying a time slot at which a location request is to be serviced.

74. An apparatus as defined in claim 73, wherein said scheduler is operative to compute an actual time to service a given location request based at least in part on the first and second labels of nodes in said search tree.

75. A computer readable storage medium including a program element for execution by a processor to implement an apparatus for scheduling servicing of location requests by a PDE, comprising:

a) a scheduling module for accepting as input expiry times data indicative of a plurality of expiry times relating to respective location requests for computing an order for servicing the location requests by the PDE at least in part on a basis on the expiry times of the location requests;

b) an output module for interfacing with the PDE allowing the PDE to service the location requests according to the order determined by said scheduler.

76. A computer readable storage medium as defined in claim 75, wherein said scheduling module is operative to insert and remove data elements in a storage medium defining a sequence of slots such that the data elements are arranged according to the order for servicing the location requests computed by said scheduling module.

77. A computer readable storage medium as defined in claim 76, wherein each data element is associated to a location request.

78. A computer readable storage medium as defined in claim 77, wherein said scheduling module is operative to re-compute the order of the data elements in the storage medium when new expiry times data associated with a new location request is received by said scheduling module.

79. A computer readable storage medium as defined in claim 78, wherein each slot in the sequence of slots corresponds to a point in time at which the PDE is expected to service the location request of a data element stored in the slot.

80. A computer readable storage medium as defined in claim 79, wherein the re-computation includes for a new location request identifying a slot in the sequence of slots that corresponds to a point in time for servicing the new location request that is within the expiry time of the location request.

81. A computer readable storage medium as defined in claim 80, wherein the re-computation includes identifying a slot in the sequence of slots that corresponds to a latest point in time for servicing the new location request, without exceeding the expiry time of the new location request.

82. A computer readable storage medium as defined in claim 80, wherein if the slot that corresponds to the latest point in time for servicing the new location request is vacant, said scheduling module is operative for storing a data element associated to the new location request in the slot that corresponds to the latest point in time.

83. A computer readable storage medium as defined in claim 82, wherein if the slot that corresponds to the latest point in time for servicing the new location request is occupied by a data element associated with a prior location request, then said scheduling module is operative for:

a) displacing the data element associated with the prior location request to a slot corresponding to an earlier point in time for servicing the prior location request to vacate the slot containing the data element associated with the prior location request;

b) inserting the data element associated with the new location request in the vacated slot.

84. A computer readable storage medium as defined in claim 76, wherein the data elements are arranged according to a search tree.

85. A computer readable storage medium as defined in claim 84, wherein each data element is associated to a location request and each data element is represented by a node in said search tree.

86. A computer readable storage medium as defined in claim 85, wherein the nodes of said search tree are ordered according to the expiry times of the respective location requests.

87. A method for scheduling servicing of location requests by a PDE, comprising:

a) receiving expiry times data indicative of a plurality of expiry times relating to respective location requests;

b) processing the expiry times data for determining an order for servicing the location requests by the position determination equipment at least in part on a basis on the expiry times of the location requests;

c) interfacing with the PDE for allowing the PDE to service the location requests according to the determining.

88. An apparatus for scheduling servicing of location requests by a PDE, comprising:

a) an input for receiving data elements from an entity, the data elements indicative of respective location requests;

b) the location requests including delayed-type location requests, a location request data element associated with a delayed-type location request including expiry time data;

c ) a scheduler for determining when location requests are to be serviced, the determining being such that the servicing of at least some delayed-type location requests is postponed artificially;

d) an output for interfacing with the PDE allowing the PDE to service the location requests according to the determining.

89. An apparatus as defined in claim 88, wherein the determining is such that the servicing of the delayed-type location requests is postponed artificially without exceeding the expiry-time data of the respective delayed-type location requests.

90. An apparatus as defined in claim 88, wherein said scheduler includes a storage medium defining a sequence of slots for holding data elements according to the determining.

91. An apparatus as defined in claim 90, wherein each data element in said storage medium. is associated to a location request.

92. An apparatus as defined in claim 91, wherein said scheduler is operative to re-compute the order of the data elements in said storage medium when new expiry times data associated with a new location request is received at said input.

93. An apparatus as defined in claim 89, wherein the data elements are arranged according to a search tree.

94. An apparatus as defined in claim 93, wherein each data element is associated to a location request and each data element is represented by a node in said search tree.

95. An apparatus as defined in claim 94, wherein the nodes of said search tree are ordered according to the expiry times of the respective location requests.

96. A method for scheduling servicing of location requests by a PDE, comprising:

a) receiving data elements from an entity, the data elements indicative of respective location requests, the location requests including delayed-type location requests, a location request data element associated with a delayed-type location request including expiry time data;

b) determining when location requests are to be serviced, the determining being such that the servicing of at least some delayed-type location requests is postponed artificially;

c) interfacing with the PDE allowing the PDE to service the location requests according to the determining.

97. A method as defined in claim 96, wherein the determining is such that the servicing of the delayed-type location requests is postponed artificially without exceeding the expiry time data of the respective delayed-type location requests.

98. A computer readable storage medium including a program element for execution by a processor to implement an apparatus for scheduling servicing of location requests by a PDE, comprising:

a) a scheduling module for accepting as input data elements from an entity, the data elements indicative of respective location requests, the location requests including delayed-type location requests, a location request data element associated with a delayed-type location request including expiry time data, said scheduling module being operative for determining when location requests are to be serviced, the determining being such that the servicing of at least some delayed-type location requests is postponed artificially;

b) an output module for interfacing with the PDE allowing the PDE to service the location requests according to the determining.

99. A computer readable storage medium as defined in claim 98, wherein the determining is such that the servicing of the delayed-type location requests is postponed artificially without exceeding the expiry time data of the respective delayed-type location requests.

100. An apparatus for scheduling servicing of location requests by a PDE, comprising:

a) an input for receiving a plurality of data elements from an entity, the plurality data elements indicative of respective location requests;

b) the location requests including delayed-type location requests, a location request data element associated with a delayed-type location request including expiry time data;

c) a scheduler for;

i) identifying among the delayed-type location requests, two or more delayed-type location requests that can be serviced by a common location query to the PDE;

ii) determining at least in part on the basis of the respective expiry times of the delayed-type location requests identified at (i) when to issue the common location query to the PDE;

d) an output for issuing the common location query.

101. A method for scheduling servicing of location requests by a PDE, comprising:

i) receiving a plurality of data elements from an entity, the plurality data elements indicative of respective location requests, the location requests including delayed-type location requests, a location request data element associated with a delayed-type location request including expiry time data;

ii) identifying among the delayed-type location requests, two or more delayed-type location requests that can be serviced by a common location query to the PDE;

iii) determining at least in part on the basis of the respective expiry times of the delayed-type location requests identified at (ii) when to issue the common location query to the PDE;

iv) issuing the common location query.

102. A computer readable storage medium including a program element for execution by a processor to implement an apparatus for scheduling servicing of location requests by a PDE, comprising:

a) a scheduling module for accepting a plurality of data elements from an entity, the plurality data elements indicative of respective location requests, the location requests including delayed-type location requests, a location request data element associated with a delayed-type location request including expiry time data, said scheduling module being operative for;

i) identifying among the delayed-type location requests, two or more delayed-type location requests that can be serviced by a common location query to the PDE;

ii) determining at least in part on the basis of the respective expiry times of the delayed-type location requests identified at (i) when to issue the common location query to the PDE;

b) an output module for issuing the common location query.

103. An apparatus for scheduling servicing of location requests by a PDE, comprising:

a) Input means for receiving expiry times data indicative of a plurality of expiry times relating to respective location requests;

b) Scheduler means for processing the expiry times data for determining an order for servicing the location requests by the PDE at least in part on a basis on the expiry times of the location requests;

c) output means for interfacing with the PDE allowing the PDE to service the location requests according to the order determined by said scheduler.

104. An apparatus for scheduling servicing of location requests by a PDE, comprising:

a) input means for receiving data elements from an entity, the data elements indicative of respective location requests, the location requests including delayed-type location requests, a location request data element associated with a delayed-type location request including expiry time data;

b) scheduling means for determining when location requests are to be serviced, the determining being such that the servicing of at least some delayed-type location requests is postponed artificially;

c) output means for interfacing with the PDE allowing the PDE to service the location requests according to the determining.

105. An apparatus for scheduling servicing of location requests by a PDE, comprising:

a) input means for receiving a plurality of data elements from an entity, the plurality data elements indicative of respective location requests, the location requests including delayed-type location requests, a location request data element associated with a delayed-type location request including expiry time data;

b) scheduling means for;

i) identifying among the delayed-type location requests, two or more delayed-type location requests that can be serviced by a common location query to the PDE;

ii) determining at least in part on the basis of the respective expiry times of the delayed-type location requests identified at (i) when to issue the common location query to the PDE;

c) output means for issuing the common location query.

106. A memory for storing data for access by an application program being executed on a data processing device used in a communications network adapted to provide alert-based services for which corresponding alert conditions to be met by mobile stations are defined, comprising:

a secondary memory for holding a plurality of data structures, the data structures being associated with respective non-overlapping time intervals, each of the data structures containing information relevant to a respective category of alert conditions that requires a current time to be included in the time interval associated with that data structure;

a primary memory for storing the one data structure associated with the time interval that includes the current time.

107. A method of creating a data structure for access by an application program being executed on a data processing device used in a communications network adapted to provide alert-based services for which corresponding alert conditions to be met by mobile stations are defined, each alert condition corresponding to an alert region, comprising:

defining a subdivision of the network into nodes;

computing, for each node, the nearest alert region;

merging together into a single cell for each alert region, those nodes having that alert region as the nearest alert region;

maintaining a data structure that is indicative of the locations covered by each cell and the alert condition associated with that cell.

108. A method as defined in claim 107, each alert condition further corresponding to an alert time, the method further comprising:

maintaining separate data structures for at least two sets of alert conditions corresponding to respective disjoint time blocks, each set of alert conditions including those alert conditions corresponding to alert times contained within the respective time block.

109. A method of delivering an alert-based communications service relevant to a mobile station in a communications network, wherein the alert-based communications service is associated with an alert condition to be satisfied by the mobile station, comprising:

obtaining location data about the mobile station for a first time instant;

predicting location data about the mobile station for a second time instant after the first time instant based on the location data about mobile station for the first time instant;

if the mobile station is predicted to be within the alert region at the second time instant, triggering the firing of an alert at or after the second time instant.

110. A method as defined in claim 109, wherein predicting location data is based on recent information regarding the mobile station.

111. A method as defined in claim 109, wherein predicting location data is based on historical information regarding the mobile station.

112. A method as defined in claim 109, wherein predicting location data is based on current information regarding other mobile stations in the network.