Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
217 words
A vehicle location detecting system comprising: a heading sensor (3) for detecting changes in the heading of a vehicle as it moves over streets; a distance sensor (4) for detecting distances traveled by said vehicle; a road map memory (5) for storing a map data base; location detecting means (7) for detecting a first estimated location (P G ) of said vehicle; and correction arithmetic means (8) for calculating a second estimated location of said vehicle from said distances detected by said distance sensor (4) and said changes in said heading detected by said heading sensor (3), for detecting an optimum vehicle location (P M ) of said vehicle by calculating a degree of similarity (S) between said second estimated location and said map data base obtained from road map memory (5), for calculating a first probability area (σ G ) of said first estimated location (P G ) including an actual location of said vehicle and a second probability area (σ M ) of said optimum vehicle location (P M ) including an actual location of said vehicle, and for correcting said second estimated location with the aid of said first estimated location (P G ) in accordance with said degree of similarity, first probability area (σ G ) and second probability area (σ M ).
Claim 2
Dependent Claim
217 words
A vehicle location detecting system comprising: a heading sensor (3) for detecting changes in the heading of a vehicle as it moves over streets; a distance sensor (4) for detecting distances traveled by said vehicle; a road map memory (5) for storing a map data base; location detecting means (7) for detecting a first estimated location (P G ) of said vehicle; and correction arithmetic means (8) for calculating a second estimated location of said vehicle from said distances detected by said distance sensor (4) and said changes in said heading detected by said heading sensor (3), for detecting an optimum vehicle location (P M ) of said vehicle by calculating a degree of similarity (S) between said second estimated location and said map data base obtained from road map memory (5), for calculating a first probability area (σ G ) of said first estimated location (P G ) including an actual location of said vehicle and a second probability area (σ M ) of said optimum vehicle location (P M ) including an actual location of said vehicle, and for correcting said second estimated location with the aid of said first estimated location (P G ) in accordance with said degree of similarity, first probability area (σ G ) and second probability area (σ M ).
Claim 3
Dependent Claim
51 words
A vehicle location detecting system as set forth in claim 1, wherein said correction arithmetic means (8) corrects said second estimated location with the aid of said first estimated location (P G ), when said optimum vehicle location (P M ) has not been obtained by calculating said degree of similarity.
Claim 4
Dependent Claim
75 words
A vehicle location detecting system as set forth in claim 1, wherein, even when said optimum vehicle location (P M ) has been obtained by calculating said degree of similarity, said correction arithmetic means (8) corrects said second estimated location with the aid of said first estimated location (P G ), if a distance difference (δd) between said optimum vehicle location and said first estimated location (P G ) is above a reference value (d1).
Claim 5
Dependent Claim
39 words
A vehicle location detecting system as set forth in claim 3, wherein said reference value (d) is determined in accordance with a size of said first probability area (σ G ) of said first estimated location (P G ).
Claim 6
Dependent Claim
63 words
A vehicle location detecting system as set forth in claim 1, wherein, when said first probability area (σ G ) of said first estimated location (P G ) and said second probability area (σ M ) of said optimum vehicle location (P M ) are overlapped, said correction arithmetic means (8) corrects said optimum vehicle location (P M ) to the overlapped part.
Claim 7
Dependent Claim
37 words
A vehicle location detecting system as set forth in claim 1, wherein said radio navigation system comprises a global positioning system wherein the location of a vehicle is detected using a plurality of satellites (7a, 7b, 7c).