Map database apparatus

• US 6,233,521 B1
• Filed: 06/18/1999
• Issued: 05/15/2001
• Est. Priority Date: 12/18/1996
• Status: Expired due to Term

• Current Assignee: Clarion Co., Ltd. (Faurecia SA)
• Original Assignee: Xanavi Informatics Corporation (Hitachi, Ltd.)
• Inventors: Nomura, Takashi
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Donnelly, Arthur D.
• Application Number:
  US09/335,774
• Time in Patent Office: 697 Days
• Field of Search: 701/208, 701/209, 701/212, 701/211, 701/200, 340/998, 340/990, 340/995, 731/78.R
• US Class Current: 701/208
• CPC Class Codes: G01C 21/3878 Hierarchical structures, e.g. layering
• CPC Class Codes: G01C 21/3881 Tile-based structures
• CPC Class Codes: G09B 29/003 Maps
• CPC Class Codes: G09B 29/106 using electronic means

Abstract

A map database apparatus is provided in which: meshes that are achieved by dividing a map into a plurality of portions are used as management units; sets of data related to the meshes are stored in a specific order; a management table that manages the sets of data related to the meshes is provided; and the management table has a parameter that makes it possible to determine an access address of a set of data related to a mesh present in a surrounding area of a specific mesh through calculation based upon the specific mesh.

Claims

1. A map database apparatus in which

meshes that are achieved by dividing a map into a plurality of portions are used as management units, comprising:

sets of data related to said meshes that are stored in a specific order; and

a management table that manages said sets of data related to said meshes and has a parameter that makes it possible to determine an access address of a set of data related to a mesh present in a surrounding area of a specific mesh through calculation based upon said specific mesh.

2. A map database apparatus according to claim 1, wherein:

said parameter corresponds to data sizes of said sets of data related to said meshes.

3. A map database apparatus according to claim 1, wherein:

said map is divided longitudinally and laterally into a matrix;

said sets of data related to said meshes are stored in an order in which said sets of data related to said meshes are arranged in a row direction; and

said parameter comprises an address of a mesh positioned at a front end of a row and data sizes of sets of data related to meshes arranged in said row.

6. A map database apparatus according to claim 1, wherein:

said map is divided longitudinally and laterally into a matrix;

said management table is constructed so that said management table corresponds to said matrix of meshes divided longitudinally and laterally and a mesh present in a surrounding area of a specific mesh can be recognized based upon information related to said matrix in said management table.

4. A recording medium recording a map database in which:

meshes that are achieved by dividing a map into a plurality of portions are used as management units;

sets of data related to said meshes are stored in a specific order;

a management table that manages said sets of data related to said meshes is provided; and

said management table has a parameter that makes it possible to determine an access address of a set of data related to a mesh present in a surrounding area of a specific mesh through calculation based upon said specific mesh.

5. A navigation apparatus, comprising:

a map database device in which meshes that are achieved by dividing a map into a plurality of portions are used as management units, sets of data related to said meshes are stored in a specific order, a management table that manages said sets of data related to said meshes is provided, and said management table has a parameter that makes it possible to determine an access address of a set of data related to a mesh present in a surrounding area of a specific mesh through calculation based upon said specific mesh; and

a control device that performs route searching and controls a monitor to display a road map and a result of route searching by using database in said map database device.

7. A navigation apparatus according to claim 5, wherein:

said map is divided longitudinally and laterally into a matrix;

said management table is constructed so that said management table corresponds to said matrix of meshes divided longitudinally and laterally and a mesh present in a surrounding area of a specific mesh can be recognized based upon information related to said matrix in said management table; and

said control device recognizes the mesh present in a surrounding area of said specific mesh based upon said information related to said matrix in said management table, obtains a parameter of said recognized mesh from said management table, and determines an access address of a set of data related to said recognized through calculation.