WO2004112413A1

WO2004112413A1 - Method for supplying map data using a mobile communication device and system for enabling the method

Info

Publication number: WO2004112413A1
Application number: PCT/KR2003/002222
Authority: WO
Inventors: Jin Beom Kim; Hee Back Lee
Original assignee: Thinkware Systems Corporation
Priority date: 2003-06-18
Filing date: 2003-10-22
Publication date: 2004-12-23
Also published as: JP2006527838A; AU2003273091A1; KR100620238B1; KR20040110257A

Abstract

The present invention relates to a method and system for supplying map data using a mobile communication device, and more particularly, to a method and system for supplying map data having a subset of a full map to a mobile communication device. According to the present invention, there is provided a method for supplying map data using a mobile communication device, comprising the steps of receiving simple map data associated with a predetermined path from a predetermined map data supply server; receiving a current position of the mobile communication device using a GPS receiver; and displaying the current position on a display means of the mobile communication device by matching the current position to the simple map data, wherein the simple map data are map data including road data corresponding to the path among road data, and the road data include first road data associated with a first road and second road data associated with a second road, which connects nodes on the first road and the other nodes that are not located on the first road, and wherein the node is an intersection on a road or a blind alley on a road. According to the present invention, there are disclosed a method and system for supplying a map data wherein simple map data being map data including only road data associated with a predetermined path and POI(Point of Interest) data are transmitted to a mobile communication device, thus reducing the amount of data transmitted to the mobile communication device. Therefore, the time from when a user requests map data to when the user receives the requested data is shortened.

Description

Method For Supplying Map Data Using A Mobile Communication Device And

System For Enabling The Method

Technical Field The present invention relates to a method and system for supplying map data using a mobile communication device, and more particularly, to a method and system for supplying map data having a subset of a full map to a mobile communication device.

Background Art A navigation system is a system that provides traffic information to vehicles such as automobiles using an artificial satellite and is also referred to as an automatic navigation system. Such a navigation system receives predetermined data from Global Positioning System (GPS) satellites orbiting the earth using a GPS receiver and calculates its own position based on the received data. There are a number of GPS satellites orbiting the earth. A navigation system can receive GPS signals from three GPS satellites no matter where the vehicle is located on the earth and calculate its own position based on the GPS signals received from the three GPS satellites. The navigation system provides a variety of traffic information to vehicles such as automobiles based on the information on its own position calculated as such. Although this navigation system has been usually employed in the position determination for and the navigation of large carriers such as aircrafts or ships, it has recently been widely used even in automobiles and the like. The navigation system provides a user with a variety of information including current position information of a vehicle, routing information from a current position to a destination of a vehicle, map information related to the position and routing information, traffic information and the like.

Since using a map allows the user to easily understand the information on the current position and the like when the user receives the current position information and the like from the navigation system, the map information is generally provided to the user together with the current position information and the like.

According to the prior art, such map information has been provided to a user via a storage medium such as CD ROM or DVD ROM. Such a conventional navigation system reads, if necessary, the map information stored in the storage medium such as CD ROM and then displays the read information on a predetermined display means. However, when the map information is updated in the conventional navigation system, the storage medium itself such as CD ROM should be replaced, and thus, this is very troublesome whenever the map information is updated later on. In other words, financial and time loss occurs because the user should continue to purchase CD ROMs containing the updated map information from a CD ROM provider. Further, since it is impossible for the map information provider to provide a user with a CD ROM in which the updated map information has been reflected in real time, the updated map information (for example, when roads, buildings and the like are newly created or destroyed) cannot be provided to the user in real time. Likewise, if a path is searched based on existing map information and the searched path is provided to a user, there is a problem in that any change in map information is not reflected in the path information provided to the user. In addition, according to another prior art referred to as so-called "telematics", navigation services using mobile devices such as mobile phones have been provided. The telematics services can guide a user to destination using voice data. Further, when a traffic accident happens to the user's car, the telematics services automatically track the position of the accident car using GPS satellites and transmit the information on the position of the accident car to rescue services, hospitals or the like that are located nearest to the position of the accident, so that rescue activities can be promptly performed. In conventional navigation services using mobile phones, however, there is a problem in that the map information cannot be stored in the mobile phone due to its limited memory capacity. Therefore, since vehicle position information, traffic information and the like have been provided to the user in the form of voice or text without map information, it can cause inconvenience to the user when utilizing a conventional navigation system.

Accordingly, there is a need for a navigation system that can reflect updated map information related to roads, etc. in real time by supplying map information to a mobile device via a communication network. In other words, if traffic information is provided in real time through a mobile communication device, a user can receive the most recent traffic information while driving. If map information is provided to a mobile device via a wireless communication network, it is an important issue to reduce the time taken in providing a map in order to provide the mobile device with map information in real time.

However, the data transfer rate between a mobile communication device and a predetermined map data supply server is usually slow compared to a wired communication network. Further, the data transfer rate is not always constant, but varies depending on conditions. Therefore, there is the possibility that the user cannot receive map data when the data transfer rate is low.

In a prior art, however, existing map data as used in a wired communication network are transmitted to a mobile communication device without special preparation. Thus, the prior art cannot solve the mentioned problem.

Disclosure of Invention

The present invention is conceived to solve the aforementioned problems in the prior art. An object of the present invention is to provide a method and system for supplying map data, wherein simple map data of map data including only road data associated with a predetermined path and POI(Point of Interest) data are transmitted to a mobile communication device, thus reducing the amount of data transmitted to the mobile communication device. Another object of the present invention is to provide a map data supply system, wherein only map data associated with a predetermined turning point is displayed in a mobile communication device, whereby the data transfer amount between the mobile communication device and a map data supply server that supplies the map data and the amount of work done is reduced in the mobile communication device and the data supply server.

A further object of the present invention is to provide a method and system for supplying map data, wherein map data whose error is corrected are provided to a user, by matching the current position of a mobile communication device is input using a GPS receiver to an appropriate position on simple map data. According to the present invention for achieving the objects and solving the problems in the prior art, there is provided a method for supplying map data using a mobile communication device, comprising the steps of receiving simple map data associated with a predetermined path from a predetermined map data supply server; receiving a current position of the mobile communication device using a GPS receiver; and displaying the current position on a display means of the mobile communication device by matching the current position to the simple map data, wherein the simple map data are map data including road data corresponding to the path among road data, and the road data include first road data associated with a first road and second road data associated with a second road, which connects nodes on the first road and the other nodes that are not located on the first road, and wherein the node is an intersection on a road or a blind alley on a road.. According to an aspect of the present invention, there is provided a method for supplying map data, wherein the step of displaying the current position on a display means of the mobile communication device by matching the current position to the simple map data comprises the steps of determining a position in which the current position is mapped to the simple map data, as a reference position; performing orthogonal projection onto a road located within a predetermined distance from the reference position to determine first candidate positions; calculating distances from the reference position to the first candidate positions; determining second candidate positions satisfying a predetermined criterion among the first candidate positions; selecting a candidate position, of which the distance is minimum, among the second candidate positions; and determining the selected second candidate position as a position matched to the simple map data.

In addition, according to the present invention, there is provided a method for supplying map data using a mobile communication device, comprising the steps of maintaining full map data and one or more simple map data in a map database; receiving a request for map data associated with a predetermined path from the mobile communication device of a user; selecting either the full map data or the simple map data according to a predetermined criterion; and transmitting the selected map data to the mobile communication device, wherein the full map data include a map data for displaying a map and the simple map data, and the map data includes linear data, text data and polygon data, and wherein the simple map data include path data, and the path data include linear data associated with a road corresponding to the path.

According to an aspect of the present invention, the step of maintaining full map data and one or more simple map data in a map database may comprise the steps of receiving input of selection for map data from the user and selecting either the full map data or the simple map data based on the input.

According to another aspect of the present invention, the step of maintaining full map data and one or more simple map data in a map database may comprise the steps of measuring a data transfer rate with the mobile communication device and selecting either the full map data or the simple map data based on the measured data transfer rate.

In addition, according to the present invention, there is provided a computer-readable recording medium containing program for implementing a method for supplying map data.

In addition, according to the present invention, there is provided a system for supplying map data using a mobile communication device, comprising a map database for maintaining full map data and one or more simple map data therein; a receiving unit for receiving a request for map data associated with a predetermined path from a mobile communication device of a user; a map data selection unit for selecting either the full map data or the simple map data according to a predetermined criterion; and a transmission unit for transmitting the selected map data to the mobile communication device, wherein the full map data include a map data for displaying a map and the simple map data, and the map data includes linear data, text data and polygon data, and wherein the simple map data include path data, and the path data include linear data associated with a road corresponding to the path.

In addition, according to the present invention, there is provided a system for supplying map data using a mobile communication device, comprising a positional data receiving unit for receiving a current position and direction of movement of the mobile communication device using a GPS receiver; a position decision unit for determining whether the mobile communication device is located within a predetermined distance from a predetermined turning point located along the direction of movement based on the current position; a map data receiving unit for receiving a map data associated with the turning point from a predetermined map data supply server; and a display means for displaying the map data when it is determined that the mobile communication device is located within the predetermined distance. Brief Description of Drawings

FIG. 1 shows a network configuration of a mobile communication device in which a map data supply system that performs a map data supply method according to an embodiment of the present invention is included. FIG. 2 is a flowchart illustrating the steps for embodying a map data supply method according to an embodiment of the present invention.

FIG. 3 is a view illustrating an example of road data in the map data supply method according to an embodiment of the present invention.

FIG. 4 is a view illustrating the necessity for map matching in an embodiment of the present invention.

FIG. 5 shows a map displayed based on first road data corresponding to a first road and second road data corresponding to a second road in an embodiment of the present invention.

FIG. 6 is a flowchart illustrating the steps for embodying a map data supply method according to another embodiment of the present invention.

FIG. 7 shows is a view illustrating an example of data stored in a map database in the map data supply method according to another embodiment of the present invention.

FIG. 8 is a block diagram illustrating a map data supply system according to an embodiment of the present invention.

FIG. 9 is a block diagram illustrating a map data supply system according to another embodiment of the present invention.

FIG. 10 is a block diagram illustrating a map data supply system according to a further embodiment of the present invention. FIG. 11 is a diagram for explaining a map data supply system according to a still further embodiment of the present invention.

FIG. 12 is an inner block diagram showing a typical computer system in accordance with still further embodiment of the present invention.

Best Mode for CarryinR Out the Invention

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. A map data supply method according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. The map data supply method according to this embodiment is performed in a predetermined map data supply system on the part of a mobile communication device. FIG. 1 shows a network configuration of a mobile communication device having built the map data supply system therein. Reference numeral 110 indicates a map data supply server, and reference numeral 130 indicates a mobile communication device connected to the map data supply server 110 via a communication network 120. The map data supply server 110 provides a predetermined map data to the mobile communication device 130. The map data supply system embedded in the mobile communication device 130 is not shown in the drawing.

FIG. 2 is a flowchart illustrating the steps for embodying a map data supply method according to an embodiment of the present invention. The map data supply system receives simple map data associated with a predetermined path from a predetermined map data supply server 110 (S201). The simple map data are map data including road data corresponding to the path among road data. The road data includes first road data associated with a first road, and second road data associated with a second road that connects nodes on the first road and the remaining nodes that are not located on the first road. The node is an intersection on a road or a blind alley on a road.

The map data supply method according to this embodiment enables display on the mobile communication device 130 as well as a path search and map matching, by using only the simple map data without using additional map data.

The map data supply server 110 maintains therein simple map data as digital map data for which a path search can be made and transmits simple map data corresponding to a predetermined path to the mobile communication device 130.

The road data are data for specifying a road on a map and may be defined in various ways. FIG. 3 is a diagram for explaining exemplary road data. In FIG. 3, the road data include nodes, links and interpolation points. Dark points indicated by Nl designate nodes, and lines that connect the nodes indicated by Ll, L2 and L3 designate links. The node is information for indicating an intersecting point where roads cross or a blind alley on a road. The link is information for indicating a road between nodes. Furthermore, the interpolation point is information for indicating a place through which the road passes on a curved road. Generally, as curvature of a road increases, a greater number of interpolation points are required in order to display the road.

As such, road data corresponding to a road can be defined. In addition, the road data may be defined in a variety of ways. Each road may be specified using the road data. Map data usually include most road data such as express highways, national roads, provincial roads, residential street roads and so on.

On the contrary, the present invention differs from the prior art in that simple map data include only road data corresponding to a predetermined path among the road data.

The map data supply system receives the current position of the mobile communication device 130 using a GPS receiver (S202) and matches the current position to the simple map data (S203 to S208). Before the "current position" received using the GPS receiver is displayed on a predetermined map, a map matching process is usually performed in order to correct error such as errors in a current position received using a GPS receiver, and errors in a map data itself. Taking FIG. 4 as an example, if the current position received using the GPS receiver is directly matched to the map data, there is a problem in that a user is displayed on the position of Youngpoong Bldg. even though the user is driving a vehicle. Thus, it is necessary to modify the current position such that it is displayed on a road along which the user is driving. This process is called map matching. In the map data supply method according to the embodiment, the current position is matched to the simple map data.

Steps S203 to S208 will be described in detail with reference to FIG. 5. FIG. 5 shows a map displayed based on the first road data corresponding to the first road and the second road data corresponding to the second road in an embodiment of the present invention. In FIG. 5, the thick road indicates the first road corresponding to the path and the remaining roads indicate the second road. Further, white circles indicated by reference numeral 501 designate the aforementioned nodes, reference numeral 502 indicates a reference position as described later, and gray circles indicated by reference numerals 503a to 503c indicate first candidate positions.

The map data supply system determines a position in which the received current position is mapped to the simple map data as a reference position 502 (S203) and also determines first candidate positions 503a, 503b and 503c by performing orthogonal projection onto a road located within a predetermined distance (15) from the reference position 502 (S204). Regarding map matching, error in a GPS receiver is in range of 200 m (although the error has a radius of about 100 m before 1999, the error has a radius of about several tens of meters from which selective availability (SA) being a kind of noise that is intentionally sent with it carried on radio waves received using the GPS receiver). Even in case of a differential GPS (DGPS) used to correct the error, the error is in range of 5 m. The map matching is for correcting error on road data corresponding to a predeteπnined road (in particular, the error may be high in a curved road). Since it is rarely considered that the reference position and distance on road data corresponding to a road along which the user's vehicle is driving on the simple map data are spaced apart by over a predetermined distance, the map data supply system performs the orthogonal projection onto roads only located within the predetermined distance (15). The map data supply system calculates a distance dl from the reference position

502 to the first candidate position 503a, a distance d2 from the reference position 502 to the first candidate position 503b and a distance d3 from the reference position 502 to the first candidate position 503c (S205). The map data supply system then determines a second candidate position, which satisfies a predetermined reference, among the first candidate positions 503a to 503c (S206).

According to another embodiment of the present invention, the step (S206) comprises the steps of receiving a progress direction or speed of the mobile communication device 130 using the GPS receiver, and determining a position selected based on the progress direction or speed as the second candidate position, among the first candidate positions 503a to 503c.

For example, in FIG. 5, if a progress direction of the mobile communication device 130 received using a GPS receiver is "north", the first candidate position 503a among the first candidate positions 503a to 503c may be determined as a second candidate position. If the progress direction is "north-northeast", the first candidate position 503b may be determined as a second candidate position.

Furthermore, assuming that the input speed is 80 km/h and a road including the first candidate position 503c is a one-lane road and is a residential street, it is sensibly difficult for a vehicle to run 80 km/h on a residential street road. Accordingly, one of the first candidate positions 503a and 503b except for the first candidate position 503c is decided as a second candidate position.

In the map data supply system, however, there is a case where the second candidate position cannot be decided based on the progress direction and speed. For example, although the input progress direction is "west" in FIG. 5, there is a case where none of the first candidate positions 503a to 503c corresponds to the progress direction. This may happen due to a case where data input in an initial state where a GPS receiver is powered are incorrect. According to another embodiment of the present invention, if the second candidate position among the first candidate positions cannot be decided based on the progress direction and speed, the map data supply system further receives a current position of the mobile communication device 130 using the GPS receiver and then selects new first candidate positions based on the current position. Furthermore, the map data supply system further receives a progress direction or speed of the mobile communication device 130 in a current state using the GPS receiver and then determines a second candidate position among the new first candidate positions based on the newly inputted progress direction or speed.

In other words, if the second candidate position cannot be decided based on the progress direction or speed, the map data supply system does not use data relating to the progress direction or speed, but uses a progress direction or speed that is input next time, so that an exact matching can be made.

The map data supply system selects a candidate position having minimum distances dl, d2 and d3 from the determined second candidate positions (S207). For example, if dl = 5 m, d2 = 5.5 m and d3 = 6 m, and second candidate positions selected based on the progress direction and speed are the first candidate position 503a and the first candidate position 503b, the map data supply system selects the first candidate position 503a having the distance of 5 m, which is a minimum.

The selected second candidate position is determined as a position matched to the simple map data (S208). The map data supply system displays the simple map data whose matched position is determined on the display means of the mobile communication device 130 (S209). As described above, in the map data supply method according to this embodiment, full map data including all the linear data, text data and polygon data are not used, but simple map data including linear data (in particular, road data for the first road and the second road) associated with a road corresponding to the path are provided to the mobile communication device 130 as map data. It is therefore possible to reduce the data transfer rate between the map data supply server 110 and the mobile communication device 130. Accordingly, data transfer time is reduced, and the delay time from when a request for transmission of map data is made to when the current position of the mobile communication device 130 is matched to the map data and is then displayed on the display means, is reduced.

Furthermore, according to another embodiment of the present invention, the map data supply system clips only road data located within a predetermined distance from the first road data among road data included in the simple map data and then displays the clipped data on the display means (S209). This is for the purpose of preventing data of less necessity from being processed and displayed since roads far from the first road data by over a predetermined distance (for example, 500m) are rarely used by users.

Meanwhile, regarding the clipping, simple map data clipped in the map data supply server 110 may be transmitted, or simple map data clipped in a map information supply system that received the simple map data may be displayed on the display means.

In addition, according to another embodiment of the present invention, the simple map data may include N^th road data other than the first road data and the second road data. The N^th road data may be defined similarly as the second road data and are road data associated with an N^th road, which connects nodes on a (N-l)^th road and the remaining nodes that are not located on the (N-l)^th road. The simple map data are consecutively expanded from the second road data.

The map data supply system provides more detailed road data for a predetermined section of the path than for other sections of the path. The predetermined section corresponds to a section of a path such as a place where a road is complicated, for which more detailed road data needs to be provided to a user of the mobile communication device 130. In the above, the map data supply system may provide road data of a high degree with respect to the predetermined section and road data of a low degree with respect to the other sections. For example, only first and second road data are displayed on the display means for a predetermined section (a), whereas first, second, third and fourth road data are displayed on the display means for a predetermined section (b). With this configuration, the map data supply system can provide detailed information on sections for which more detailed information need to be provided to a user, while reducing the size of data to be processed.

It has been described in this embodiment that the simple map data include the first road data and the second road data. In a map data supply method according to another embodiment of the present invention, however, the simple map data are map data including only road data associated with a road corresponding to the path. In other words, a map is displayed with only a road network and main POI(Point of Interest) data on a searched path. In this embodiment, the data transfer amount and the delay time can be further reduced since the mobile communication device receives only road data corresponding to the first road data.

Meanwhile, if a simple map containing the first and second road data is employed, deviation of a path can be more easily determined compared to a simple map containing only the first road data. In other words, since the current position of the mobile communication device 130 can be matched to the second road data as well as the first road data as shown in FIG. 5, it may be determined that the mobile communication device 130 (i.e., a vehicle that a user drives) deviates from the path if the current position of the mobile communication device 130 is matched to the second road data not the first road data associated with the first road corresponding to the path. Therefore, the map data supply system determines that the mobile communication device 130 deviates from a path if a current position of the mobile communication device 130 is matched to the second road data, and then takes predetermined measures such as supply of such fact to the user.

If the simple map contains only the first road data, the map data supply system can determine the mapped current position, which is far from the first road data by a predetermined distance, as deviation of a path. As such, the map data supply system can determine that the mobile communication device 130 has deviated from a path only after it runs along the path beyond this distance.

Hereinafter, a map data supply method according to another embodiment of the present invention will be described. The map data supply method according to this embodiment is performed in a predetermined map data supply system (not shown) on the part of the map data supply server in FIG. 1.

FIG. 6 is a flowchart illustrating the steps for embodying the map data supply method according to this embodiment. The map data supply system has full map data and one or more simple map data maintained in a predetermined map database (S601). The full map data includes map data for displaying a map, and the simple map data. The map data includes linear data, text data and polygon data. The simple map data include path data, and the path data include linear data associated with a road corresponding to the path.

The simple map data may be first simple map data including only first road data associated with a first road corresponding to a predetermined path to be described later, as in the aforementioned embodiment. The simple map data may be second simple map data including even second road data corresponding to a second road, which connects nodes on the first road and the remaining nodes that are not located on the first road, as well as the first road data. In the same manner, the simple map data may be expanded to third simple map data, which further contain third road data corresponding to a third road that connects nodes on the second road and the remaining nodes that are not located on the second road. As such, N^th simple map data including N^th road data can be defined. The map database maintains therein one or more simple map data among the first to N^th simple map data. Although the present context has been described in view of road data, the simple map data may further contain POI(Point of Interest) data as well as road data.

The map data supply system receives a request for a map data associated with the predetermined path from the mobile communication device 130 (S602). In response to the request, the map data supply system transmits map data selected from the map database to the mobile communication device 130. In other words, the map data supply system has simple map data, which are digital map data for which a path search is possible, maintained in the map database. The map data supply system clips some of the simple map data, which are associated with the predetermined path, and then transmits the clipped simple map data to the mobile communication device 130, so that the simple data can be map-matched and displayed on the mobile communication device 130.

According to another embodiment of the present invention, the map data supply system measures the data transfer rate with the mobile communication device 130 in response to the request (S603). The map data supply system selects either full map data or simple map data based on the data transfer rate obtained as a result of the measurement (S604) and transmits the selected map data to the mobile communication device 130 (S605). In the map data supply method according to this embodiment, the map database stores a data transfer rate corresponding to map data therein, as shown in FIG. 7, and selects map data corresponding to the measured data transfer rate.

As described above, the size of the simple map data is smaller than that of the full map data since it is a subset of the full map data. Further, the size of a (N-I)' simple map data is relatively smaller than that of the N¹ simple map data. Therefore, by transmitting map data of an appropriate size that is selected from full map data or one or more simple map data maintained in the map database based on the data transfer rate, it is possible to reduce the delay time from when a user requests map data to when the user receives the requested map data.

According to another embodiment of the present invention, the map data supply system may further receive a request for map data and selected map data (S602), and transmit map data selected by a user to the mobile communication device 130 (S605).

The mobile communication device 130 receives the map data sent by the map data supply system (S606) and receives the current position of the mobile communication device 130 using a GPS receiver (S607). The mobile communication device 130 matches the current position to the map data and then displays the matched current position on the display means of the mobile communication device 130 (S 608).

According to another embodiment of the present invention, the method for matching the current position to the map data comprises the steps of determining a position in which the current position is matched to the received map data as a reference position, determining a first candidate position by performing orthogonal projection onto a road located within a predetermined distance from the reference position, calculating the distance from the reference position to the first candidate position, determining a second candidate position that satisfies a predetermined reference among the first candidate positions, selecting a candidate position having a minimum distance among the second candidate position, and determining the selected candidate position as a position which is matched to the received map data.

Furthermore, according to another embodiment of the present invention, the step of determining the second candidate position that satisfies the predetermined reference from the first candidate position comprises the steps of receiving a progress direction or speed of the mobile communication device from the mobile communication device using the GPS receiver, and determining the first candidate position, which is selected from the first candidate positions based on the progress direction or speed, as the second candidate position.

Such a matching process is in principle same as the process of matching to simple map data (corresponding to steps S203 to S208) in the aforementioned embodiment. Therefore, detailed explanation on it will be omitted for simplicity.

In addition, there is provided a computer-readable recording medium containing program for implementing a method for supplying map data according to the embodiments of the present invention. The computer-readable recording medium may contain program instructions, data files, data structures, or a combination thereof. The program instructions may be ones that are specially designed or written for the present invention or may be ones that are well known to those skilled in the field of computer software. For example, the computer-readable recording medium includes a magnetic medium such as a hard disk, a floppy disk and a magnetic tape, an optical medium such as CD-ROM and DVD, a magneto-optical medium such as a floptical disk, and hardware devices such as read only memory (ROM), random access memory (RAM) and flash memory that are specially configured to store and execute the program instructions. The medium may be a transfer medium such as an optical or metal line and waveguide, including a carrier wave that transmits signals for specifying the program instructions, data structures and the like. Examples of the program instructions may include high-level language codes executable by a computer using an interpreter as well as machine language codes such as those written by a compiler.

Hereinafter, a map data supply system according to an embodiment of the present invention will be described. FIG. 8 is a block diagram illustrating a map data supply system according to this embodiment. The map data supply system 810 includes a map database 811, a receiving unit 812, a map data selection unit 813 and a user transmission unit 814. The map data supply system 810 provides predetermined map data to a mobile communication device 830 from a communication network 820.

The map database 811 maintains foil map data and one or more simple map data therein. The foil map data and the simple map data have been described in the aforementioned embodiment. Thus, detailed description on them will be omitted for simplicity. The receiving unit 812 receives a request for map data associated with a predetermined path from the mobile communication device 830 via the communication network 820. In response to the request, the map data selection unit 813 selects either the foil map data or the simple map data, which are maintained in the map database 811, according to a predetermined reference. According to another embodiment of the present invention, the map data supply system 810 includes a data transfer rate measurement unit (not shown) for measuring the data transfer rate with the mobile communication device 830. The map data selection unit 813 selects either the foil map data or the simple map data on the basis of the measured data transfer rate. Accordingly, by selecting simple map data when the data transfer rate is slow, it is possible to reduce the transfer time of map data in the user transmission unit 814, as will be described later.

Further, according to another embodiment of the present invention, the receiving unit 812 further receives selection data for selecting the map data as well as the request for the map data. The map data selection unit 813 selects either the foil map data or the simple map data based on the select data. Accordingly, a user of the mobile communication device 830 can select either to receive more rapid map data (when the simple map data option is selected) or more detailed map information (when the foil map data option is selected).

The user transmission unit 814 transmits the selected map data to the mobile communication device 830.

Through the above-mentioned construction, the mobile communication device 830 can be provided with map data. In particular, simple map data having a data size smaller than that of full map data are maintained in a map database as well as the full map data, and map data selected according to a predetermined reference are provided.

Consequently, map data can be transmitted to mobile communication devices in real time. A map data supply system according to another embodiment of the present invention will now be described. FIG. 9 is a block diagram illustrating a map data supply system according to this embodiment. A map data supply system 910 comprises a map data receiving unit 931, a position receiving unit 932, a map-matching unit 933 and a display means 934. The map data receiving unit 931 receives simple map data associated with a predetermined path from a predetermined map data supply server 910. In order to receive simple map data, a user may transmit an input for specifying the path to the map data supply server 910.

The position receiving unit 932 receives the current position of a user's mobile communication device using a GPS receiver, and the map-matching unit 933 matches the current position to the simple map data. The matched simple map data are displayed on the display means 934.

The simple map data and the matching process have been described in the aforementioned embodiment. Therefore, detailed description on them will be omitted for simplicity.

Through the above construction, the user can more rapidly receive simple map data having a small data size than in case of full map data. By matching the current position to the simple map data, a current position of the mobile communication device can be represented at an appropriate location on map data. A map data supply system according to still another embodiment of the present invention will now be described with reference to FIG. 10 and FIG. 11. FIG. 10 is a block diagram illustrating a map data supply system 1030 according to this embodiment.

The map data supply system 1030 comprises a positional data receiving unit 1031, a position decision unit 1032, a map data receiving unit 1033, a display means 1034, and a user transmission unit 1035.

The positional data receiving unit 1031 receives the current position and direction of a user's mobile communication device using a GPS receiver. As shown in FIG. 11, the position decision unit 1032 determines whether the mobile communication device is located within a predetermined distance dl 1 from a predetermined turning point located on the progress direction (north) based on the current position. In FIG. 11, reference numeral 1101 indicates the current position of the mobile communication device on map data, reference numeral 1102 designates POI(Point of Interest) data and reference numeral dl l indicates the predetermined distance.

The turning point indicates portions (intersections, left turn or right turn road, etc.) where a user can turn among the roads. The map data receiving unit 1033 receives map data associated with the turning point from the predetermined map data supply server 1010. The display means 1034 displays the map data associated with the turning point if the mobile communication device is located within the predetermined distance dl l from the turning point as a result of the determination. In other words, as shown in FIG. 11, if the turning point is a crossroads, the display means 1034 displays road data corresponding to the crossroads and POI(P oint of Interest) data around the crossroads, among the map data.

Since a user of a mobile communication device usually runs on a straight road until the user reaches a predetermined turning point, there is little possibility that the user may refer to map data associated with the straight road, prior to reaching the designated turning point. At the turning point, however, there is a high possibility that the user may refer to map data associated with the turning point.

Therefore, map data associated with turning points are displayed on the mobile communication device only around the turning points along the progress direction. It is thus possible to reduce the amount of work done by the mobile communication device.

Furthermore, the map data receiving unit 1033 can receive only map data associated with the turning point without the need to receive map data associated with the remaining points. In the map data supply system 1030 according to this embodiment, the amount of data transferred with the map data supply server 1010 is reduced, whereby the amount of work done in a mobile communication device as well as the map data supply server 1010 can be reduced.

In the map data supply system 1030 according to still another embodiment of the present invention, the map data receiving unit 1033 receives the map data if the mobile communication device is located with the predetermined distance dl 1 as a result of the determination. In other words, according to this embodiment, the map data receiving unit 1031 does not receive map data for the turning point at one time, but receives relevant map data in real time based on the input current position.

Furthermore, according to still another embodiment of the present invention, the map data supply system 1030 further comprises a user transmission unit 1035 for transmitting a request for map data corresponding to a predetermined path to the map data supply server 1010. The map data receiving unit 1033 receives map data associated with a turning point existing in the path. According to this embodiment, the map data receiving unit 1033 receives map data associated with a turning point existing in the path even when the mobile communication device is not located within the predetermined distance dl 1 from the turning point. Accordingly, the number that data are transmitted and received to and from the map data supply server 1010 can be reduced.

Meanwhile, FIG. 12 shows an inner block diagram of a typical computer system in accordance with an embodiment of the present invention. The computer system 1200 includes any number of processors 1201 (also referred to as central processing units, or CPUs) that are coupled to storage devices including primary storage 1202 (typically a random access memory, or "RAM"), primary storage 1203 (typically a read only memory, or "ROM"). As is well known in the art, primary storage 1203 acts to transfer data and instructions uni-directionally to the CPU and primary storage 1202 is used typically to transfer data and instructions in a bi-directional manner. Both of these primary storage devices may include any suitable type of the computer-readable media described above. A mass storage device 1204 is also coupled bi-directionally to CPU 1201 and provides additional data storage capacity and may include any of the computer-readable media described above. The mass storage device 1204 may be used to store programs, data and the like and is typically a secondary storage medium such as a hard disk that is slower than primary storage. A specific mass storage device such as a CD-ROM 1206 may also pass data uni-directionally to the CPU. Processor 1201 is also coupled to an interface 1205 that includes one or more input/output devices such as such as video monitors, track balls, mice, keyboards, microphones, touch-sensitive displays, transducer card readers, magnetic or paper tape readers, tablets, styluses, voice or handwriting recognizers, or other well-known input devices such as, of course, other computers. Finally, processor 1201 optionally may be coupled to a computer or telecommunications network using a network connection as shown generally at 1207. With such a network connection, it is contemplated that the CPU might receive information from the network, or might output information to the network in the course of performing the above-described method steps. The above-described devices and materials will be familiar to those of skill in the computer hardware and software arts.

The hardware elements described above may be configured (usually temporarily) to act as one or more software modules for performing the operations of this invention.

Industrial Applicability

According to the present invention, there are disclosed a method and system for supplying a map data wherein simple map data being map data including only road data associated with a predetermined path and POI(Point of Interest) data are transmitted to a mobile communication device, thus reducing the amount of data transmitted to the mobile communication device. Therefore, the time from when a user requests map data to when the user receives the requested data is shortened. Furthermore, according to a map data supply system, only map data associated with predetermined turning points are displayed on a mobile communication device. A data transfer amount between a mobile communication device and a map data supply server that provides map data is reduced. The amount of work done in the mobile communication device and the data supply server can also be reduced. Furthermore, according to a method and system for supplying map data, the current position of a mobile communication device inputted using a GPS receiver is matched to an appropriate position on simple map data. Therefore, the map data whose error on GPS receiver or map data is corrected are provided to a user.

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents.

Claims

1. A method for supplying map data using a mobile communication device, comprising the steps of: (a) receiving simple map data associated with a predetermined path from a predetermined map data supply server;

(b) receiving a current position of the mobile communication device using a GPS receiver; and

(c) displaying the current position on a display means of the mobile communication device by matching the current position to the simple map data, wherein the simple map data are map data including only road data associated with a road corresponding to the path among road data.

2. A method for supplying map data using a mobile communication device, comprising the steps of:

(a) receiving simple map data associated with a predetermined path from a predetermined map data supply server;

(b) receiving a current position of the mobile communication device using a GPS receiver; and (c) displaying the current position on a display means of the mobile communication device by matching the current position to the simple map data, wherein the simple map data are map data including road data corresponding to the path among road data, and the road data include first road data associated with a first road and second road data associated with a second road, which connects nodes on the first road and the other nodes that are not located on the first road, and wherein the node is an intersection on a road or a blind alley on a road.

3. The method as claimed in claim 2, wherein the step (c) comprises the step of displaying only the road data located within a predetermined distance from the first road data.

4. The method as claimed in claim 1 or 2, wherein the step (c) comprises the steps of: determining a position in which the current position is mapped to the simple map data, as a reference position; determining first candidate positions by performing orthogonal projection onto a road located within a predetermined distance from the reference position; calculating distances from the reference position to the first candidate positions; determining second candidate positions satisfying a predetermined criterion among the first candidate positions; selecting a candidate position, of which the distance is minimum, among the second candidate positions; and determining the selected second candidate position as a position matched to the simple map data.

5. A method for supplying map data using a mobile communication device, comprising the steps of:

(a) maintaining full map data and one or more simple map data in a map database;

(b) receiving a request for map data associated with a predetermined path from the mobile communication device of a user; (c) selecting either the full map data or the simple map data according to a predetermined criterion; and

(d) transmitting the selected map data to the mobile communication device, wherein the full map data include a map data for displaying a map and the simple map data, and the map data includes linear data, text data, and polygon data, and wherein the simple map data include path data, and the path data include linear data associated with a road corresponding to the path.

6. The method as claimed in claim 5, wherein the step (c) comprises the steps of: receiving input of selection for map data from the user; and selecting either the full map data or the simple map data based on the input.

7. The method as claimed in claim 5, wherein step (c) comprises the steps of: measuring a data transfer rate with the mobile communication device; and selecting either the full map data or the simple map data based on the measured data transfer rate.

8. The method as claimed in claim 5, further comprising the steps of: receiving the selected map data; receiving a current position of the mobile communication device using a GPS receiver; and displaying the current position on a display means of the mobile communication device by matching the current position to the received map data, wherein these steps are performed in the mobile communication device.

9. The method as claimed in claim 8, wherein the step of displaying the current position on a display means of the mobile communication device by matching the current position to the received map data comprise the steps of: determining a position in which the current position is mapped to the received map data, as a reference position; determining first candidate positions by performing orthogonal projection onto a road located within a predetermined distance from the reference position; calculating distances from the reference position to the first candidate positions; determining second candidate positions satisfying a predetermined criterion among the first candidate positions; selecting a candidate position, of which distance is minimum, among the second candidate positions; and determining the selected candidate position as a position matched to the received map data.

10. The method as claimed in any one of claims 1, 2, and 9, wherein the step of determining the second candidate positions satisfying the predetermined criterion among the first candidate positions comprises the steps of: receiving a direction of movement or speed of the mobile communication device from the mobile communication device using the GPS receiver; and determining one of the first candidate positions, which is selected based on the direction of movement or speed, as a second candidate position.

11. A computer-readable recording medium in which a program for implementing a method according to any one of claims 1, 2, and 5 to 9 is recorded.

12. A system for supplying map data using a mobile communication device, comprising: a map database for maintaining full map data and one or more simple map data therein; a receiving unit for receiving a request for map data associated with a predetermined path from a mobile communication device of a user; a map data selection unit for selecting either the full map data or the simple map data according to a predetermined criterion; and a transmission unit for transmitting the selected map data to the mobile communication device, wherein the full map data include a map data for displaying a map and the simple map data, and the map data includes linear data, text data and polygon data, and wherein the simple map data include path data, and the path data include linear data associated with a road corresponding to the path.

13. A system for supplying map data using a mobile communication device, comprising: a map data receiving unit for receiving simple map data associated with a predetermined path from a predetermined map data supply server; a position receiving unit for receiving an input of a current position of the mobile communication device using a GPS receiver; a map matching unit for matching the current position to the simple map data; and a display means for displaying the matched simple map data, wherein the simple map data are map data including road data associated with a road corresponding to the path among road data.

14. A system for supplying map data using a mobile communication device, comprising: a positional data receiving unit for receiving a current position and direction of movement of the mobile communication device using a GPS receiver; a position decision unit for determining whether the mobile communication device is located within a predetermined distance from a predetermined turning point located along the direction of movement based on the current position; a map data receiving unit for receiving a map data associated with the turning point from a predetermined map data supply server; and a display means for displaying the map data when it is determined that the mobile communication device is located within the predetermined distance.

15. The system as claimed in claim 14, wherein the map data receiving unit receives the map data when it is determined that the mobile communication device is located within the predetermined distance.

16. The system as claimed in claim 14, further comprising a user transmission unit for transmitting a request for map data corresponding to a predetermined path to the map data supply server, wherein the map data receiving unit receives map data associated with the turning point located along the path.