Abstract:
A location-relevant service system provides location-relevant information to, or performs location-relevant service for, a first mobile unit based on the location of a second mobile unit. In one instance, the first mobile unit is fixed on a vehicle, while the second mobile unit can be provided as a cellular phone. In another instance, the first mobile unit is provided with a display panel, so that authentication can be achieved through providing the display location information to a location-relevant service server using the second mobile unit.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application continuation of U.S. patent application Ser. No. 11/069,154 filed on Mar. 1, 2005 now U.S. Pat. No. 7,227,499, which is a division of U.S. patent application Ser. No. 09/599,053 filed on Jun. 21, 2000 now U.S. Pat. No. 6,882,313, both of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a location-relevant service; in particular, the present invention relates to a location-relevant service accessible by multiple mobile devices. 
     2. Discussion of the Related Art 
     Location-relevant services, which provide information or perform services based on the geographical location of a mobile client, are becoming more available. A location-relevant service can be used, for example, by a trucking company to track the positions of its vehicles in service. Another application of location-relevant systems is to provide travel-related services (e.g., driving directions) based on the position of the client. One example of a location-relevant service is described, for example, in copending U.S. patent application “Method for Distribution of Locality-Relevant Information using a Network” (Copending Application”), Ser. No. 09/422,116, filed Oct. 20, 1999. To provide an example regarding the architecture and application of a location-relevant information system, the disclosure of the Copending Application is hereby incorporated by reference in its entirety. 
     Typically, a location-relevant system includes a location-relevant service server accessible by multiple mobile units over a communication system, which includes wires links to the mobile units. The mobile units provide their positions based on a positioning system. The position of a mobile unit can be provided by, for example, the Global Positioning System (GPS) or, in a cellular telephone network, by a process called triangulation which is based on signal delays from system base stations of known fixed locations. Due to technology limitations at the present time, it is costly to integrate the capabilities of both positioning and wireless communication of such a mobile unit into a hand-held device. In addition, hand-held positioning devices are also typically less accurate than their more sophisticated bulky counterparts. Therefore, a mobile unit in a location-relevant service is typically fixedly installed on a vehicle. However, a mobile unit fixedly installed on a vehicle cannot provide the convenience and mobility of a hand-held unit. 
     Another desirable application that is not known in the prior art is accessing from a mobile unit location-relevant service based on the position of another mobile unit. 
     SUMMARY OF THE INVENTION 
     The present invention provides a location-relevant service system which includes (a) a location-relevant service server accessible over a data network (e.g., the Internet); (b) a first mobile unit coupled to the data network over a first wireless link which provides a position of the first mobile unit over the wireless link to the location-relevant service server; and (c) a second mobile unit coupled to the data network which receives from the location-relevant service server location-relevant service based on the position of the first mobile unit. In one embodiment, the second mobile unit couples to the location-relevant service server over a second wireless link independent of the first wireless link. Alternatively, the first and second mobile units can share the first wireless link, which can be provided by either of the mobile units. Further, the first and second units can also communicate over a direct wired or wireless link. In a wired link environment, the wired link can be provided through a docking station in the first mobile unit adapted for accommodating the second mobile unit. The electrical interface between the first and second mobile units under such an arrangement can be proved by a standard interface, such as an industry standard serial bus commonly found in portable devices, such as a cellular telephone, lap top computer or a personal digital assistant. 
     The location-relevant service system of the present invention can operate in at least two modes: on-demand or “pushed.” Under on-demand operation, location-relevant service is provided in response to a query received from the second mobile unit. Alternatively, under the pushed operation either the second mobile unit or a non-mobile unit can request a selected location-relevant service to be provided to the second mobile unit upon occurrence of predetermined events, or satisfaction of certain conditions (e.g., during a specified time period). 
     Location-relevant services can provide such information as traffic conditions, entertainment information, or travel-related information (e.g., detailed driving directions) relevant to the locality of the first mobile unit. Alternatively, the first mobile unit can be installed in conjunction with a monitor that monitors the operation conditions of a vehicle. In that configuration, the first mobile unit can report operations or maintenance conditions of the vehicle to other users (e.g., the second mobile unit) through the location-relevant service server. 
     In one application, a user who is seeking a real property can specified in the location-relevant service server a search request for a list of real properties for inspection. The search result can be pushed to his cellular phone (i.e., second mobile unit, in this instance) based on the position receiver (e.g. GPS receiver) installed in his vehicle, when he arrives at the vicinity and requests from the second mobile unit his search results. 
     In addition to the GPS system, the present invention can also be used in conjunction with a terrestrial triangulation-based system. In one embodiment, the first mobile unit receives or computes its position using terrestrial triangulation. 
     In one application, the two mobile units can be used to authenticate a user in a business transaction. For example, the user conducting business on a cellular telephone can be authenticated by providing the location-relevant service server the position of the first mobile unit. (For example, the user is conducting this transaction from his vehicle, where the first mobile unit is installed). The location-relevant service server can independently verify [verified] this position by querying the first mobile unit. In such an application, if the first mobile unit is provided a display, the user can read the position off the display and key in the position information using the keypad on the second mobile unit (e.g., a cellular telephone). 
     The present invention is better understood upon consideration of the detailed description below and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows one embodiment of the present invention in a location-relevant service system  100 . 
         FIG. 2  illustrates a query-based operation of one embodiment of the present invention. 
         FIG. 3  illustrates a “push-based” operation of one embodiment of the present invention. 
         FIG. 4  shows system  400 , in a second embodiment of the present invention. 
         FIG. 5  shows system  500 , in a third embodiment of the present invention. 
         FIG. 6  illustrates a method for obtaining a receiver position based on the global positioning system (GPS). 
         FIG. 7  illustrates a method for obtaining a receiver position based on terrestrial triangulation. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention provides access to a location-relevant service from a mobile communication device based on the position of another mobile unit.  FIG. 1  shows one embodiment of the present invention in a location-relevant service system  100 . As shown in  FIG. 1 , a conventional mobile unit  101  for accessing location-relevant service is in communication in a conventional manner with a location-relevant service server  106  over a communication or data network, such as the Internet. Mobile unit  101  consists of both position receiver  103  and communication portion  102 . In addition, mobile unit  101  may include a visual display panel for displaying the position information received at position receiver  103 . Position information can be expressed as actual longitudes and latitudes, or simply a location code. In addition, the “age” of the location information (i.e., the elapsed time since the last time mobile unit  101  computes its position) can also be displayed. 
     As illustrated by system  100 , mobile unite  101  can send its position data, for example, over a wireless link  113  with wireless gateway  104 . Positional data can be received, for example, from a GPS system or a terrestrial triangulation-based system.  FIGS. 6 and 7  illustrate methods for obtaining a receiver position based on a global positioning system and a terrestrial triangulation system, respectively. As shown in  FIG. 6 , in a GPS system, receiver  605  receives from satellites  601 - 604  respective positions P 1 , P 2 , P 3 , and P 4  and their times of transmission, Using its local time t, receiver  605  computes distances S 1 , S 2 , S 3 , and S 4 , which are respective distances of satellites  601 - 604  from receiver  605 . Position Pr of receiver  605  can then be computed conventionally as a function of P 1 , P 2 , P 3 , P 4 , S 1 , S 2 , S 3 , and S 4 . As shown in  FIG. 7 , under a terrestrial triangulation method, land-based transmitters  702 - 704  of known locations P 1 , P 2 , and P 3  each provide a signal from which receiver  701  computes respective distances S 1 , S 2  and S 3  between receiver  701  and each of transmitters  702 - 704 . The position Pr of receiver  701  can be computed conventionally as a function of P 1 , P 2 , P 3 , S 1 , S 2 , and S 3 . In addition to the computer position of mobile device  101 , the time at which the position was obtained can be also provided location-relevant service server  106 . This information would allow the user or location-relevant service server  106  to determine whether or not a more or less frequent update is necessary. The direct ion of travel of mobile unit  101  can also be provided to location-relevant service sever  106 . (Direction of travel can be used, for example, in a driving direction service to provide more accurate “turn by turn” driving directions—i.e., additional turns may be necessary to reorient the vehicle towards the destination) 
     Wireless gateway  104  relays the position data from mobile unite  101  over the Internet to location-relevant server  106  over via internet gateway  105 . As in the system described in the Copending Application incorporated by reference above, location-relevant sever  106  is accessible over the Internet by desk top client device  112  (e.g., a desktop computer) using conventional internet connection  11 . Desktop client device  112  can be used to control subsequent processing of the position data received at location-relevant service server  106 . 
     Unlike prior art systems, however, system  100  allows a second mobile device  110  (e.g., a cellular telephone, a personal digital assistant, or a laptop computer) to access information or service provided by location-relevant service server based on the position of mobile unit  101 . As shown in  FIG. 1 , location-relevant service server  106  provides location-relevant information to mobile device  110  by making such information available at an information depository  107  (e.g., a web server) accessible by mobile device  110  through wireless gateway  109  and internet gateway  108  via wireless link  119  and conventional data communication links  117  and  118 . In one embodiment, a user can access information depository  107  using a browser adapted for a wireless communication protocol (e.g., WAP). (Although shown here as separate units, information depository  107  and location-relevant service server  106  can be implemented by the same server unit). 
     To access location-relevant service based on the position of mobile unit  101 , the user of mobile device  110  provides authentication information (e.g., user identification and password) to location-relevant service server  106 . After establishing that the user of mobile device  110  has the requisite rights, location-relevant server  106  provides location-relevant service to the user of mobile device  110 . 
     System  100  can operate under at least two modes of operations: “query-based” and “push-based” operations.  FIG. 2  illustrates a query-based operation of one embodiment of the present invention. As shown in  FIG. 2 , under a query-based operation, location-relevant service is provided only when the user of mobile device  110  sends out a request for location-relevant service (step  201 ). At step  202 , where location-relevant service server  106  receives the services request, it determines (step  203 ) if it requires an update of the position of mobile device  101 . If an updated position is required, a request is sent to mobile device  101  to obtain mobile device  101 &#39;s current position. Otherwise, at step  205 , the most recently acquired position information stored at location-relevant service server  106  is used. Regardless of whether an update is obtained, the position data is used to render location-relevant service (step  206 ). Results or returned information is then provided to the user at mobile device  110  (step  207 ). 
       FIG. 3  illustrates a “push-based” operation of one embodiment of the present invention. Under the push-based operation of  FIG. 3 , at steps  301  and  302 , mobile device  110  receives a command for a selected location-relevant service and enables the corresponding service at location-relevant service server  106 . The selected service can be activated according to some conditions, such as a specified position reported by mobile unit  101 . At the same time, at regular time intervals, mobile unit  101  provides its current position to location-relevant service server  106 . Location-relevant service server  106  waits on the specified conditions for triggering the selected location-relevant service (steps  303  and  304 ). When the conditions for the selected service are met, the selected service is performed in accordance with the position of mobile unit  101  (step  305 ). Depending on whether the selected service is to remain active (e.g., prior to the expiration of a specified time period), location-relevant service server  106  returns to wait for the triggering conditions (step  306 ), or proceed with other location-relevant services (step  307 ), as required. 
     Examples of other location-relevant information that can be provided includes: traffic, operating or maintenance conditions regarding the vehicle, entertainment (e.g., movies or shows played at nearby cinemas or theaters) or travel-related information (e.g., locations of nearby hotels, points of interests, gas stations, restaurants, driving directions etc.) In system  100 , for example, prior to a trip, a user can specified from his desktop personal computer a list of location-related service requests. The user seeking to buy real estate, for example, may set requests for locations of open-house events, which will then be downloaded to mobile device  110  in the form of a paging message or an email, when mobile device  101 —which is installed in the user&#39;s car—arrives at the specified geographical vicinity. 
     The information at location-relevant service server  106  can be shared among users for many purposes. For example, the present invention provides a method for authentication for on-line transactions. For example, a user completing an on-line transaction with mobile device  110  can sign the transaction using the position data displayed on the display panel of mobile unit  101 . The elapsed time since the position data was obtained can also be displayed on the display panel and used to achieve further robustness. The other party to the transaction can authenticate the user through location-relevant service server  106 , which independently query mobile unit  101  to obtain its position. 
     In system  100 , mobile unit  101  and mobile device  110  communicate via separate wireless links  113  and  119 . However, the operations described above and the attendant benefits can be achieved similarly using systems  400  and  500  of  FIGS. 4 and 5 , respectively, in alternative embodiments of the present invention. To simplify the following discussion and to avoid repetition, like elements in  FIGS. 1 ,  4 , and  5  are provided like reference numerals. In each of systems  400  and  500 , rather than mobile unit [device]  101  sending positional data to location-relevant service server  106  via an independent communication link, the position information data of mobile unit [device]  101  and communication between mobile device  110  and location-relevant service server  106  share a common wireless link and an internet gateway. In system  400 , mobile unit  101  and mobile device  100  communicate with each other over wireless link  402 , and communicate with location-relevant service server  106  through mobile device [unit]  110 . Alternatively, as shown in  FIG. 5 , mobile unit  101  and mobile device  110  communicate over a wired link  501 , and communicate with location-relevant service server  106  through mobile unit  101 &#39;s wireless link  113 . Wired link  501  can be implemented, for example, by a docking station through a standard interface. For example, if mobile unit  101  is a lap top or a personal digital assistant, such an interface can be provided by a  1394  serial bus interface. As in  FIG. 1 , in systems  400  and  500 , location-relevant service server  107  can be accessed from non-mobile or desktop client  112 . 
     The above detailed description is provided to illustrate specific embodiments of the present invention and is not intended to be limiting. Numerous modifications and variations within the scope of the present invention are possible. The present invention is set forth in the following claims.