Display method and apparatus for arranging order of listing points of interest for navigation system

• US 6,839,628 B1
• Filed: 06/13/2003
• Issued: 01/04/2005
• Est. Priority Date: 06/13/2003
• Status: Active Grant

• Current Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Original Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Inventors: Tu, Ihung S.
• Primary Examiner(s): Marc-Coleman, Marthe Y.
• Application Number:
  US10/460,960
• Publication Number:
  US 20040254723A1
• Time in Patent Office: 571 Days
• Field of Search: 701/209, 701/200, 701/201, 701/202, 701/203, 701/208, 701/210, 701/211, 701/214, 701/225, 340/988, 340/990, 340/995.1
• US Class Current: 701/209
• CPC Class Codes: G01C 21/3679 Retrieval, searching and output of POI information, e.g. hotels, restaurants, shops, filling stations, parking facilities G01C21/3611 takes precedence

Abstract

A display method and apparatus for navigation system enables a user easily see a list of points of interest (POIs) along a route to a destination. The POI names are arranged in the order that the user sees the POIs along the route. The method first determines a route to the destination, and specifies a search area by selecting a distance range on the route from a user position and by defining a radius of a region circle. The method further creates a plurality of region circles consecutively on the route, retrieves points of interest (POIs) within the search area, calculates a modified distance of each POI based on distances from two reference points to the POI and distances from the user position to the two reference points, and lists the POIs in the order of modified distance.

Claims

1. A display method for a navigation system for guiding a user to a destination, comprising the following steps of:

determining a route to the destination;

specifying a search area by selecting a distance range on the route from a user position and by defining a radius of a region circle;

creating a plurality of region circles consecutively on the route;

retrieving points of interest (POIs) within the search area;

calculating a modified distance of each POI based on distances from two (first and second) reference points on the route in two consecutive region circles to the POI and distances from the user position to the two centers; and

listing the POIs in the order of modified distance calculated by the above process.

2. A display method as defined in claim 1, further comprising a step of repeating the steps of retrieving POIs within the search area and calculating the modified distance of each POI to determine the order of listing the POIs.

3. A display method as defined in claim 1, wherein said step of calculating the modified distance of each POI is conducted by:

D1=[(Q_k-1+d₁₁)+(Q_k+d₁₂)]/2

where D1 is a modified distance of a particular POI, d₁₁, is a distance between the first reference point and the POI, d₁₂ is a distance between the second reference point and the POI, Q_k-1 is a distance between the user position and the first reference point, and Q_k is a distance between the user position and the second reference point.

4. A display method as defined in claim 3, wherein said first reference point is a center of one of the two consecutive region circles and the second reference point is a center of another region circle.

5. A display method as defined in claim 4, wherein said step of calculating the modified distance of each POI includes a step of prioritizing a POI whose distance d₁₁ from the first center is shorter than that of the other POIs for determining the order of listing the POIs when modified distances of two or more POIs in the consecutive two region circles are identical to one another.

6. A display method as defined in claim 1, wherein said radius of said region circle is smaller when said route to the destination is a local street than that when the route is a freeway.

7. A display method as defined in claim 6, wherein said radius of said region circle defines a width of said search area, thereby limiting a distance in a transversal direction of the route.

8. A display method as defined in claim 1, wherein said step of specifying the search area includes a step of selecting an initial search range out of a plurality of distance ranges.

9. A display method as defined in claim 4, wherein said step of creating the plurality of region circles includes a step of defining a center of a region circle at a position on the route at which a circumference of an immediately prior region circle intersects.

10. A display method as defined in claim 1, wherein said step of retrieving POIs includes a step of displaying a number of POIs in each distance range and a step of selecting a distance range to display detailed information on the POIs in the selected distance range.

11. A display method as defined in claim 10, wherein said step of retrieving POIs includes a step of stopping the retrieval of POIs when the user position is away from the route to the destination by more than a predetermined distance.

12. A display method as defined in claim 10, wherein said step of displaying the number of POIs in each distance range includes a step of displaying the distance range of the POIs with a minus sign when the user position has passed a point in the distance range along the route.

13. A display method as defined in claim 1, wherein said step of retrieving POIs includes a step of displaying a list of categories to select one of the categories of POIs to be retrieved within the search area.

14. A display apparatus for a navigation system for guiding a user to a destination, comprising:

means for determining a route to the destination;

means for specifying a search area by selecting a distance range on the route from a user position and by defining a radius of a region circle;

means for creating a plurality of region circles consecutively on the route;

means for retrieving points of interest (POIs) within the search area;

means for calculating a modified distance of each POI based on distances from two (first and second) reference points on the route in two consecutive region circles to the POI and distances from the user position to the two centers; and

means for listing the POIs in the order of modified distance calculated by the above process.

15. A display apparatus as defined in claim 14, further comprising means for repeating the processes of retrieving POIs within the search area and calculating the modified distance of each POI to determine the order of listing the POIs.

16. A display apparatus as defined in claim 14, wherein said means for calculating the modified distance of each POI conducts calculation by:

D1=[(Q_k-1+d₁₁)+(Q_k+d₁₂)]/2

where D1 is a modified distance of a particular POI, d₁₁, is a distance between the first reference point and the POI, d₁₂ is a distance between the second reference point and the POI, Q_k-1 is a distance between the user position and the first reference point, and Q_k is a distance between the user position and the second reference point.

17. A display apparatus as defined in claim 16, wherein said first reference point is a center of one of the two consecutive region circles and the second reference point is a center of another region circle.

18. A display apparatus as defined in claim 17, wherein said means for calculating the modified distance of each POI includes means for prioritizing a POI whose distance d₁₁, from the first center is shorter than that of the other POIs for determining the order of listing the POIs when modified distances of two or more POIs in the consecutive two region circles are identical to one another.

19. A display apparatus as defined in claim 14, wherein said radius of said region circle is smaller when said route to the destination is a local street than that when the route is a freeway.

20. A display apparatus as defined in claim 19, wherein said radius of said region circle defines a width of said search area, thereby limiting a distance in a transversal direction of the route.

21. A display apparatus as defined in claim 14, wherein said means for specifying the search area includes means for selecting an initial search range out of a plurality of distance ranges.

22. A display apparatus as defined in claim 16, wherein said means for creating the plurality of region circles includes means for defining a center of a region circle at a position on the route at which a circumference of an immediately prior region circle intersects.

23. A display apparatus as defined in claim 14, wherein said means for retrieving POIs includes means for displaying a number of POIs in each distance range and means for selecting a distance range to display detailed information on the POIs in the selected distance range.

24. A display apparatus as defined in claim 23, wherein said step of retrieving POIs includes a step of stopping the retrieval of POIs when the user position is away from the route to the destination by more than a predetermined distance.

25. A display apparatus as defined in claim 23, wherein said step of displaying the number of POIs in each distance range includes a step of displaying the distance range of the PoIs with a minus sign when the user position has passed a point in the distance range along the route.

26. A display apparatus as defined in claim 14, wherein said means for retrieving POIs includes means for displaying a list of categories to select one of the categories of POIs to be retrieved within the search area.