| 摘要 |
PURPOSE:To enable quick selection of a map data indicating the current location by collating a reception frequency of a broadcasting station near a moving object with a broadcasting station data. CONSTITUTION:A memory section 1 stores a broadcasting station data S containing a position data of a broadcasting station beforehand, a receiving section 2 within a moving object detects a reception frequency (f) of a broadcasting station existing in vicinity and a collating means 3 collates the frequency (f) with the data Sb. When the receiving section 2 detect multiple frequencies (f), a station-to-station distance computing means 4 computes all of distances between broadcasting stations corresponding to the respective frequencies (f) to output a distance data Sd and furthermore, based on a combination of broadcasting stations having the distance data Sd smaller than a maximum radio wave arrival distance data Sm, an unknown broadcasting station receiving currently is identified to indicate a virtual current location of the moving object in terms of zones which can receive all of these broadcasting. Even when the frequency (f) is allotted to a plurality of broadcasting stations, any broadcasting station receiving current can be identified by the means 4 and a distance comparing means 5. |
