United States Patent [19J
`Behr et al.
`
`111111111111111111111111111111111111111111111111111111111111111111111111111
`US005543789A
`[11] Patent Number:
`[45] Date of Patent:
`
`5,543,789
`Aug. 6, 1996
`
`[54] COMPUTERIZED NAVIGATION SYSTEM
`
`[75]
`
`Inventors: David A. Behr, Roselle; Randall B.
`Jones, Downers Grove, both of Ill.
`
`[73] Assignee: Shields Enterprises, Inc., Chicago, Ill.
`
`[21] Appl. No.: 265,094
`
`[22] Filed:
`
`Jun. 24, 1994
`
`Int. Cl.6
`..................................................... GOSG 1/123
`[51]
`[52] U.S. Cl . .......................... 340/995; 340/990; 340/991;
`364/449
`[58] Field of Search ..................................... 340/988, 990,
`340/995, 991; 364/449
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`4,311,876
`4,466,125
`4,951,212
`4,954,958
`5,172,321
`5,243,528
`5,262,775
`5,283,575
`
`1/1982 Endo et al. ............................ 455/54.1
`8/1984 Kanayama .............................. 340/990
`8/1990 Kurihara et al. ........................ 340/995
`9/1990 Savage et al ........................... 364/444
`12/1992 Ghaem et al ........................... 364/444
`9/1993 Lefebvre ................................. 340/995
`11/1993 Tamai et al ............................. 340/995
`2/1994 Kao et al ................................ 340/990
`
`5,291,412
`5,291,413
`5,293,163
`5,293,484
`
`311994 Tamai et al ............................. 364/449
`311994 Tamai et al ............................. 364/449
`311994 Kakihara et al ........................ 340/988
`3/1994 Dabbs, III et al. ................ 340/825 .44
`
`OTHER PUBLICATIONS
`
`Smart cars, smart highways, collier, w. Clay and Weiland,
`Richard J., IEEE Spectrum, Apr., 1994, pp. 27-33.
`
`Primary Examiner-Brent A. Swarthout
`Attorney, Agent, or Firm-Alice 0. Martin
`
`[57]
`
`ABSTRACT
`
`The invention provides a method and system for providing
`route guidance information from a base unit to a remote unit
`in response to a request from the remote unit. The remote
`unit may be a mobile unit or a fixed unit. A query is
`formatted at the remote unit, the query including the request,
`and communicated from the remote unit to the base unit. The
`requested route guidance information is calculated at the
`base unit in response to the query, using a database located
`at the base unit. A response to the query is formatted at the
`base unit, the response including the route guidance infor(cid:173)
`mation. The response is communicated from the base unit to
`the remote unit for display.
`
`56 Claims, 3 Drawing Sheets
`
`1 - - -
`
`1
`
`MAP
`DATA BASE
`
`THIRD
`PARTY
`DATA
`INTEGRATER
`
`OnER
`INFORMATION
`PRCNIDERS
`
`80
`
`82
`
`DISTANCE
`ANO TIME
`TRAVEL
`ESTIMATOR
`
`SURROUt{)lNGS
`EXPLORER
`
`68
`
`70
`
`84
`
`86
`
`88
`
`54
`
`52
`
`50
`
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`
`74 L __
`
`QUERY
`RESOLVER
`
`62
`
`PC
`
`DISPLAY
`
`30
`
`16
`
`KBD
`28
`
`KBO
`
`46
`
`18
`
`44
`
`ZTE Exhibit 1009
`
`

`

`U.S. Patent
`
`Aug. 6, 1996
`
`Sheet 1of3
`
`5,543,789
`
`, - - - - - - - 72 - - - ,
`THIRD
`PARTY
`MAP
`DATA BASE - - - DATA
`INTEGRATER
`
`OTHER
`~~INFORMATION
`PRCNIOERS
`
`80
`
`82
`
`DISTANCE
`AND TIME
`TRAVEL
`ESTIMATOR
`
`SURROUl'l>INGS
`EXPLORER
`
`68
`
`70
`
`66
`
`QUERY
`RESOLVER
`
`64
`
`25~
`
`PC
`
`DISPLAY
`
`30
`
`16
`
`lo.E--......J CELLULAR
`SYSTEM
`38
`LAPTOP ,up MODEM
`PC
`MEM
`DISPLAY
`POS
`KBD
`44
`
`22
`
`26
`
`28
`
`46
`
`18
`
`10
`
`FIG. I
`
`54
`
`52
`
`50
`
`58
`
`20
`
`'--14
`
`ZTE Exhibit 1009 - 2
`
`

`

`U.S. Patent
`
`Aug. 6, 1996
`
`Sheet 2 of 3
`
`5,543,789
`
`ESTABLISH
`COMMUNICATION
`
`100
`
`FORMAT A
`QUERY . . . - - - - - -
`102
`
`QUERY
`RESOLUTION
`
`104
`
`TRANSMIT
`ERROR
`MESSAGE
`
`HO
`
`YES
`
`IDENTIFY
`QUERY
`TYPE
`
`112
`
`ZTE Exhibit 1009 - 3
`
`

`

`124
`
`MSG LEN
`
`128
`
`130
`
`132
`
`138
`
`140
`
`142
`
`144
`
`152
`
`120
`
`122_.K
`
`FIG. 3
`
`165
`J -166
`
`164
`
`168
`
`170
`
`172
`
`174
`
`176
`
`178
`
`180
`
`MSG LEN I ICRC !TIME STAMP !SUBSCRIBER ID !MESSAGE ID
`
`160
`
`162/
`
`FIG. 4
`
`~ •
`1'J1
`•
`~
`~ ;-
`= f"'+-
`
`>
`~
`
`~a-,
`
`~
`\C
`\C a-,
`
`00. =(cid:173)~
`~
`~
`s,
`
`~
`
`Ul
`._.
`Ul
`~
`~ ._.
`.....J
`
`00 "'
`
`ZTE Exhibit 1009 - 4
`
`

`

`5,543,789
`
`1
`COMPUTERIZED NAVIGATION SYSTEM
`
`BACKGROUND OF THE INVENTION
`
`5
`
`10
`
`-
`
`2
`medium such as CD-ROM or floppy disk, to remotely
`located mobile users may be difficult. In addition, the media
`themselves are expensive since they may generally be used
`only a single time.
`Other aspects of such prior art autonomous route guidance
`systems add to their cost and inconvenience. Because the
`systems are autonomous, they must include all components,
`including the computer, the database and the position sensor.
`Using present technology, such a system is too heavy and
`too large to be readily transported by an individual. In
`addition, the complete system has power requirements
`which make battery operation impractical. As a result,
`autonomous route guidance systems have been limited to
`installation in automobiles or other vehicles which can
`accommodate the size and power requirements of such a
`system. The current best price for a complete autonomous
`route guidance system is at least $2,000. This includes only
`the cost for a single, dedicated autonomous route guidance
`system.
`Another type of route guidance system has been tested in
`Europe using beacons to provide a guidance signal to
`on-board equipment. The system directs the user to travel
`from beacon to beacon, creating a step-wise path between an
`origin and a destination. The navigational information thus
`25 provided forms a generally inefficient routing path from
`origin to destination. In addition, such a system does not
`provide the capability to query a database for information
`about nearby points of interest and other geographical
`information.
`Therefore, there is a need for a routing and information
`system that continually provides access to up-to-date, cor(cid:173)
`rect geographic information by a remote user. There is a
`further need for a routing and information system which can
`be implemented on lightweight, portable devices for easy,
`convenient transportation and use. There is a further need for
`a routing and information system which is independent of
`any particular hardware configuration and may be imple(cid:173)
`mented on any suitably equipped data processing apparatus,
`such as a desktop personal computer, a laptop computer, a
`personal digital assistant or even a pager. There is a further
`need for a routing and information system which provides
`communication between mobile units and a base unit over
`any available channel, including wireless and wireline chan-
`nels. There is a still further need for a data communication
`protocol for providing accurate, reliable communication in
`such a system, independent of hardware configuration.
`
`The invention generally relates to a system and method
`for providing route guidance and tracking information from
`a base unit to a mobile unit over wireless and wireline
`devices. The invention more particularly relates to an appa(cid:173)
`ratus and method for providing to a mobile unit route
`guidance and tracking information which has been calcu(cid:173)
`lated at a base unit in response to a query from the mobile
`unit.
`Systems have been developed which provide geographi-
`cal or position-dependent information to a mobile user. Such 15
`systems are generally installed in an automobile or other
`vehicle. These systems generally include an on-board geo(cid:173)
`graphic database which may be accessed to determine
`geographic information, such as locations of points of inter(cid:173)
`est, directions to points of interest, and directions between a 20
`specified origin and a destination. An on-board computer
`calculates route guidance information using data from the
`database in response to user inputs.
`Such systems are known as autonomous route guidance
`systems, since they are independent and self-contained. The
`systems generally include a geographic database, position(cid:173)
`ing sensors, and a computer including a keyboard and
`display. The geographic database is a representation of a
`region or metropolitan area and may include, for example,
`street names, navigation attributes, such as tum restrictions 30
`and one-way streets, street addresses, and points of interest,
`such as airports, restaurants and museums. The positioning
`sensors may determine geographic position from RF (Radio
`Frequency) triangulation or in response to signals from, for
`example, GPS (Global Positioning System), LORAN C or
`other similar positioning systems, and from motion and
`direction detectors. The computer calculates route guidance
`information in response to inputs from the other system
`components as well as operator input. The route guidance
`information is provided to the user in the form of naviga(cid:173)
`tional text or map graphics.
`Autonomous route guidance systems have many draw(cid:173)
`backs, however, which have prevented their widespread use.
`Because the system is autonomous and has an on-board
`database, the system must include large storage capabilities
`for storing all the data which form the database. Technolo(cid:173)
`gies such as CD-ROM have allowed storage of an entire
`database but require still a tradeoff between cost and fast,
`efficient data access.
`Another problem with the database provided with autono(cid:173)
`mous route guidance systems is maintenance or currency of
`the database. As new streets are built, or as old streets are
`reconfigured, as businesses and other points of interest open
`and close, the database on CD-ROM or other media 55
`becomes out of date. In addition, when a database is com(cid:173)
`piled, it may include errors which are then replicated in the
`many copies provided to users. These errors may require
`correction in the user copies by replacing those database
`copies. Moreover, incorrect or outdated information in the 60
`database can lead to errors when calculating routes. When an
`out-of-date database does not include the information that a
`particular roadway is closed, the system may be unable to
`calculate an alternate route.
`Autonomous route guidance systems may improve the 65
`accuracy of the system by providing occasional database
`updates to users. However, distribution of the database, in a
`
`35
`
`40
`
`45
`
`50
`
`SUMMARY OF THE INVENTION
`
`The invention therefore provides a method of providing
`route guidance information from a base unit to a mobile unit
`in response to a request from the mobile unit. The method
`comprises the steps of formatting a query at the mobile unit,
`the query including the request, communicating the query
`from the mobile unit to the base unit, and calculating the
`route guidance information at the base unit in response to the
`query. The method further comprises the steps of formatting
`a response to the query at the base unit, the response
`including the route guidance information, and communicat(cid:173)
`ing the response from the base unit to the mobile unit. The
`include navigation
`information may
`remote guidance
`instructions from an origin to a destination, information
`about one or more points of interest within the region of an
`origin or other geographically referenced information.
`The invention further provides a system for communicat(cid:173)
`ing routing information between a base unit and a mobile
`unit. The system comprises input means at the mobile unit
`
`ZTE Exhibit 1009 - 5
`
`

`

`5,543,789
`
`IO
`
`30
`
`3
`for providing an origin and a destination. The system further
`comprises calculating means at the base unit for calculating
`a route between the origin and the destination. The system
`still further comprises communication means for communi(cid:173)
`cating the origin and the destination from the mobile unit to 5
`the base unit and for communicating the route from the base
`unit to the mobile unit. The routing information may include
`navigation instructions from an origin to a destination,
`information about one or more points of interest within the
`region of an origin or other geographically referenced infor-
`mation.
`The invention still further provides a method of providing
`routing information to a mobile unit. The method comprises
`the steps of providing an origin and a destination from the
`mobile unit to a base unit, the base unit located remotely
`from the mobile unit. The method further comprises the 15
`steps of calculating at the base unit a route between the
`origin and the destination, and providing the route to the
`mobile unit.
`The invention still further provides a system for providing 20
`route guidance information to a remote location from a
`central location. The system comprises a mobile unit includ(cid:173)
`ing input means for providing at least a route destination and
`output means for providing an indication of the route
`guidance information. The system further comprises first 25
`transmission means at the mobile unit for transmitting
`destination data and origin data from the mobile unit, the
`destination data being indicative of a route destination and
`the origin data being indicative of a route origin. The system
`still further comprises a base unit at the central location. The
`base unit includes first receiving means for receiving the
`destination data and the origin data from the first transmis(cid:173)
`sion means, calculating means coupled with the receiving
`means for calculating a route to the route destination from a
`route origin responsive to the destination data and the origin
`data, and second transmission means for transmitting rout-
`ing data, the routing data being indicative of the route. The
`system still further comprises second receiving means at the
`mobile unit for receiving the routing data from the second
`transmission means, the second receiving means being
`coupled with the output means for providing the route
`guidance information to the input means responsive to the
`routing data.
`The invention provides a system and method for provid(cid:173)
`ing geographically referenced information from a base unit 45
`or server to a mobile unit. The mobile unit may be a
`transportable device such as a laptop computer or personal
`digital assistant (PDA), or may be a desktop personal
`computer or any other device permitting data entry and
`display or printing of the provided information.
`The mobile unit communicates with the base unit using
`any available communication system, such as land line
`telephone link, cellular telephone or radio frequency trans(cid:173)
`mission. Queries are communicated from the mobile unit to
`the base unit. The query requests route guidance informa- 55
`tion, information about a point of interest or other geo(cid:173)
`graphical information. The query is formatted in a specified
`protocol. The base unit communicates responses to queries,
`the responses also formatted in a specified protocol. The
`responses may include, for example, textual navigational 60
`directions or maneuver maps showing graphical represen(cid:173)
`tations of street intersections and the calculated route
`through the intersection. Transmitting only a representation
`of the intersection, rather than all geographical features
`around the intersection, allows the response, including the 65
`maneuver map, to be transmitted over a low bandwidth
`channel. The invention operates independently of the com-
`
`4
`munication system and is adaptable to any system. The
`invention allows support for many different mobile unit
`platforms, taking advantage of each platform's capabilities
`while retaining as much system-level look and feel consis(cid:173)
`tency as possible.
`The base unit includes a geographical database, such as
`the Navigation Technologies Corp navigable map database.
`The geographical database stores a variety of geographical
`and position-oriented attributes, such as street addresses,
`tum restrictions and points of interest. The points of interest
`are preferably organized according to different parameters,
`including point of interest type, such as "restaurant" or
`"museum;" point of interest name; city; driving distance; or
`driving time. The base unit further includes a server for
`receiving queries from one or more mobile units, resolving
`ambiguities in the queries, determining a response to the
`query, accessing the geographical database as needed. The
`server formats a response to the query and communicates the
`response to the mobile unit.
`In a first mode of operation, an origin and a destination are
`entered at the mobile unit. The origin or the destination may
`be in the form of a street address, an intersection of two
`streets, or a point of interest previously identified in the
`geographical database. The origin and destination are com(cid:173)
`municated from the mobile unit to the base unit. The base
`unit calculates a route between the specified origin and
`destination. The routing information is communicated from
`the base unit to the mobile unit where it is displayed by the
`mobile unit. The display may be a graphical display, show(cid:173)
`ing map portions and providing travel directions along with
`a display of highway signs and other information. The
`display may be textual information, providing travel direc(cid:173)
`tions. The mobile unit may supply a digitally synthesized
`voice which audibly presents the travel directions to the user.
`In a second mode of operation, the mobile unit formulates
`a query requesting information about points of interest
`within a specified distance of an origin. The origin may be
`specified by street address, intersecting streets, by geo-
`graphic position or by reference to a point of interest. The
`query is communicated from the mobile unit to the base unit.
`The base unit uses the geographical database to formulate a
`response. The response is communicated from the base unit
`to the mobile unit for display to the user.
`In a third mode of operation, a mobile unit provides
`information specifying its location to the base unit. A control
`unit requests tracking information about the mobile unit
`from the base unit. The control unit may be, for example,
`another personal computer, coupled to the base unit through
`50 an external interface, either directly or through a commu(cid:173)
`nications network. The base unit provides to the control unit
`tracking information including the current location of the
`mobile unit with respect to the street network and the route
`covered by the mobile unit.
`The invention further provides a protocol for communi(cid:173)
`cating a query from the mobile unit to the base unit and for
`communicating a response from the base unit to the mobile
`unit. The protocol allows transmission of variable length
`messages, as required by the individual mobile unit or
`communication link. The protocol includes error checking,
`time stamping and subscriber information. The protocol
`further includes information specifying origin and destina(cid:173)
`tion, for a query, and message type and message contents,
`such as route information, for a response.
`It is therefore an advantage of the invention to provide a
`method and apparatus for providing geographically refer(cid:173)
`enced information from a base unit to a mobile unit, the
`
`35
`
`40
`
`ZTE Exhibit 1009 - 6
`
`

`

`5,543,789
`
`5
`mobile unit including only data entry and display devices
`and a communications link. It is a further advantage of the
`invention to provide this capability in a mobile unit which
`does not require on board database storage or position
`finding equipment at the mobile unit. It is a still further 5
`advantage of the invention to provide a mobile unit with
`access to a larger, more comprehensive database. For
`example, prior art CD-ROM-based databases are limited to
`600 MB of storage which may be sufficient to store map
`information for only a single metropolitan region. In con- 10
`trast, the invention allows the mobile unit to access map
`information for many metropolitan regions or an entire
`nation, as well as other information, such as on-line yellow
`page information or traffic advisory information, which may
`be provided by third party information providers. It is a still 15
`further advantage of the invention to permit automatic, real
`time database updates by maintaining the database only at
`the base unit, avoiding the need to distribute database
`updates to the mobile unit.
`It is a still further advantage of the invention to provide a
`system for communicating requests for routing information
`and responses including routing information in which the
`system is independent of the devices on which the system is
`implemented. It is a further advantage of the invention to
`provide such a system which may be implemented using any
`commonly available hardware devices, including laptop
`computers, personal digital assistants and other transport(cid:173)
`able units communicating via wireless or wireline systems.
`It is a still further advantage of the invention to efficiently
`convey complex information, including graphical informa(cid:173)
`tion, over communication channels having limited band(cid:173)
`width using data compression and a novel protocol. This
`allows a system in accordance with the invention to dynami(cid:173)
`cally transmit selected map portions for display on a capable
`mobile unit. The geographical information may be saved at 35
`the mobile unit for later retrieval and display, without having
`to again access the base unit.
`
`6
`12 and a plurality 14 of remote units arranged to commu(cid:173)
`nicate with the base unit 12. The plurality 14 of remote units
`may include, for example, a desktop personal computer 16,
`a laptop personal computer 18, or a pager 20. The plurality
`14 of remote units may include any number of mobile units.
`The base unit 12 is preferably located at a single, central
`location. One remote unit may be permanently located at a
`single site, such as desktop personal computer 16. Another
`remote unit may also be mobile or transportable, such as
`laptop personal computer 18 or pager 20. As used herein, the
`term "mobile unit" includes both remote units which may be
`permanently located at a single site or remote units which
`are mobile or transportable.
`The desktop personal computer 16 is an example of one
`type of mobile unit which may be included in the system 10.
`The desktop personal computer 16 preferably includes a
`modem 22, a memory 26, a keyboard 28, a display 30 and
`a microprocessor 32. The modem 22 is adapted to be
`coupled to a telephone line 24. The telephone line 24 is in
`turn coupled to the commercial telephone system 25. The
`20 modem 22 may be, for example, a serial (dial up line)
`modem such as a modem compatible with the AT command
`set which is built in to the desktop personal computer 16, a
`stand alone modem, or a PCMCIA modem. Alternatively,
`the modem may be for use with a specialty wireless trans-
`25 mission network such as ARDIS, CDPD (cellular digital
`packet data) or RAM. Still further, the modem may be of a
`type custom designed for the desktop personal computer 16.
`The modem 22 thus forms transmission means at the mobile
`unit for transmitting the origin and the destination and a
`30 receiving means at the mobile unit for receiving the
`responses, including the route, from the base unit 12.
`The microprocessor 32 responds to program instructions
`and data stored in the memory 26. To activate the system 10,
`a user manipulates the keyboard 28 to formulate a request.
`The request may, for example, seek the route between an
`origin and a destination. The keyboard 28 thus provides an
`input means at the mobile unit for providing an origin and
`a destination. The desktop PC 16, under control of a program
`40 of instructions stored in the memory 26, conveys the request
`over the telephone line 24 to the base unit 12. The base unit
`12 formulates a response to the request and conveys the
`response over the telephone line 24 to the desktop PC 16.
`The response to the request is displayed on the display 30.
`45 The display 30 thus forms an output means at the mobile unit
`for providing an indication of the route provided in the
`response. In addition, the response may be stored in the
`memory 26 for later retrieval and display. The memory 26
`thus provides storage means at the mobile unit for storing the
`50 route communicated from the base unit.
`The laptop personal computer 18 is another example of a
`mobile unit which may be used in the system 10. The laptop
`PC 18 includes a modem 34, a memory 40, a position locator
`42, a keyboard 44, a display 46 and a microprocessor 48.
`55 The modem 34 is coupled to an antenna 36 for sending and
`receiving cellular telephone calls in conjunction with the
`cellular telephone system 38, which is a portion of the
`commercial telephone system 25. The modem 34 may be,
`for example, any of the modem types described in conjunc-
`tion with the modem 22 of the desktop personal computer
`16.
`The microprocessor 48 operates in response to program
`instructions and data stored in the memory 40. The position
`locator 42 provides the geographical position of the laptop
`65 PC 18. For example, the position indicator 42 may perform
`RF (radio frequency) triangulation or may be responsive to
`GPS (Global Positioning System), LORAN C signals or
`
`60
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`The features of the invention which are believed to be
`novel are set forth with particularity in the appended claims.
`The invention, together with further objects and advantages
`thereof, may best be understood by making reference to the
`following description taken in conjunction with the accom(cid:173)
`panying drawings, in the several figures of which like
`reference numerals identify identical elements, and wherein:
`FIG. 1 is a functional block diagram illustrating the
`system of the invention;
`FIG. 2 is a flow diagram illustrating the method of the
`invention;
`FIG. 3 is a diagram illustrating a data communication
`protocol for communicating data from a mobile unit to a
`base unit in accordance with the invention and which may be
`used in conjunction with the system of FIG. 1 and the
`method of FIG. 2; and
`FIG. 4 is a diagram illustrating a data communication
`protocol for communicating data from a base unit to a
`mobile unit in accordance with the invention and which may
`be used in conjunction with the system of FIG. 1 and the
`method of FIG. 2.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENT
`
`FIG. 1 is a functional block diagram of a system 10
`embodying the invention. The system 10 includes a base unit
`
`ZTE Exhibit 1009 - 7
`
`

`

`5,543,789
`
`10
`
`15
`
`7
`other satellite positioning systems for providing latitude and
`longitude positioning information. The position locator 42
`thus provides a position determining means for determining
`the geographical position of the mobile unit. The laptop PC
`18, in response to the program instructions stored in the 5
`memory 40, provides a request over the commercial tele(cid:173)
`phone system to the base unit 12. The request may be, for
`example, for the route between an origin and a destination.
`The origin may be specified either by manipulating the
`keyboard 44 or by providing the latitude and longitude
`information produced by the position locator 42. The base
`unit 12 provides a response to the request to the laptop PC
`18. The response is displayed on the display 46.
`The pager 20 provides another example of a remote unit
`which may be used with the system 10. The pager 20
`includes a radio frequency (RF) interface 50 coupled to an
`antenna 52 for receiving RF signals from an antenna 54
`coupled to the base unit 12. The pager 20 further includes a
`microprocessor 56 responsive to program instructions and
`data stored in a memory 58. In response to information
`transmitted from the base unit 12 and received at the antenna
`52, the microprocessor 56 displays information, such as
`geographical directions, on a display 60.
`In another mode of operation, one mobile unit, such as the
`desktop personal computer 16, may track another mobile
`unit, such as the laptop personal computer 18, using the
`system 10. A user of the desktop personal computer 16 may
`manipulate the keyboard 28 to request route guidance infor(cid:173)
`mation such as tracking information. The request is trans(cid:173)
`mitted over the telephone line 24 to the base unit 12. The
`base unit 12 formulates a response based on the geographic
`position information provided by the position locator 42 of
`the laptop PC 18. The response is transmitted over the
`telephone line 24 to the desktop personal computer 16 for
`display on the display 30.
`Thus, the system 10 provides geo-referenced information
`over wireless and wireline devices to mobile and remote
`users. It is to be understood that the communications tech(cid:173)
`nologies and the mobile units illustrated in FIG. 1 may be
`combined in ways other than those illustrated in FIG. 1. For
`example, the desktop personal computer 16 may include an
`RF interface such as the RF interface 50 of the pager 20.
`Similarly, the modem 34 of the laptop PC 18 may be adapted
`for coupling directly to a telephone line such as telephone
`line 24. In addition, other types of mobile units, such as
`personal digital assistants (PDAs) may be included in the
`system 10. Moreover, mobile units may access the base unit
`indirectly by communicating directly with a third-party
`information provider, such as ProdigyTM, which in tum
`conveys queries to and responses from the base unit 12. In
`accordance with the invention, the system 10 operates
`independently of particular hardware configurations of the
`plurality 14 of remote units and of the communications
`system.
`The base unit 12 includes an I/O interface 62, a query
`resolver 64, a route calculator 66, a distance and time travel
`estimator 68, a surroundings explorer 70, a map data base 72
`and a third party data integrator 80. The I/O interface 62
`includes a telephone interface 74 for coupling the base unit
`12 to the commercial telephone system 25 including the
`telephone line 24. The I/O interface 62 further includes an
`RF interface 76 for coupling the base unit 12 with RF
`communication devices such as an antenna 54. The I/O
`interface 62 and the modem 22 thus provide communication
`means for communicating an origin and a destination from
`the desktop personal computer 16 to the base unit 12 and for
`communicating a route from the base unit 12 to the desktop
`
`8
`personal computer 16. The I/O interface 62, the modem 34
`and the antenna 36 provide a communication means for
`communicating the origin and the destination from the
`laptop personal computer 18 to the base unit 12 and for
`communicating the route from the base unit 12 to the laptop
`personal computer 18.
`The I/O interface 62 may further include a network
`interface 75 for coupling the base unit 12 to one or more
`wireless or wireline communication networks such as CDPD
`(cellular digital packet data), TCP/IP (transmission control
`protocol/Internet protocol), ARDIS or RAM. The I/O inter(cid:173)
`face 62 may further include an external interface 77 for
`coupling the base unit 12 to a control unit 84. The control
`unit 84 provides an external link to the base unit 12 and may
`be, for example, a personal computer coupled over a wire-
`less or wireline network or a directly-connected terminal.
`The control unit 84 may include, for example, a keyboard 86
`and a display 88. The control unit 84 may request tracking
`information about the location of one or more mobile units.
`For example, a mobile unit may be located in an armored
`20 vehicle transporting valuables along a specified route. The
`control unit may receive tracking information from the base
`unit and, if the mobile unit in the armored vehicle varies
`from the specified route by a predetermined amount, sounds
`an alarm or triggers some other action.
`The I/O interface 62, including the telephone interface 74
`and the RF interface 76, provide a means for coupling the
`base unit 12 with communications media such as the com(cid:173)
`mercial telephone system and other wireline and wireless
`devices. The I/O interface 62 thus receives queries from the
`plurality 14 of remote units and transmits the responses from
`the base unit 12 to the plurality 14 of remote units. The I/O
`interface 62 therefore provides a receiving means at the base
`unit for receiving the origin and destination and a transmit-
`ting means at the base unit for transmitting the route to a
`mobile unit.
`The query resolver 64 receives the request from the I/O
`interface 62. When a request is entered at one of the plurality
`14 of remote units, a mistake may be made. For example, in
`40 manipulating the keyboard 44 of t