| 摘要 |
An apparatus installed on a host vehicle derives travel locus/condition information relating each of a plurality of reception positions on the vehicle to a corresponding reception condition (e.g., received signal strength), and updates the information at each of successive positions along a travel locus of the vehicle. The currently obtained information is compared with reference travel locus/condition information previously obtained by travel along a reference travel locus, in the same travel direction, by the host vehicle or similar vehicle. Degrees of similarity between the currently obtained information and the reference information are evaluated, and the results used to detect changes in position of the host vehicle along a direction at right angles to its advancement direction. |
| 主权项 |
1. A terminal apparatus installed on a host vehicle, comprising
a radio communication condition acquisition unit configured for acquiring respective radio communication conditions of a plurality of radio communication positions on the host vehicle, a travel locus/condition information generating unit configured for generating a plurality of sets of travel locus/condition information respectively corresponding to the radio communication positions on the host vehicle, the travel locus/condition information for a radio communication position expressing the radio communication condition at each of respective positions on a travel locus of the host vehicle, the travel locus comprising positions successively attained by the host vehicle when moving along a specific travel direction, and a reception map acquisition unit configured for acquiring a plurality of reception maps respectively corresponding to the radio communication positions on the host vehicle, each of the reception maps comprising travel locus/condition information previously generated by the terminal apparatus of the host vehicle or of a vehicle of identical type to the host vehicle when moving along the specific travel direction; wherein the terminal apparatus is characterized in that the plurality of radio communication positions on the host vehicle are spaced apart with respect to a direction at right angles to an advancement direction of the host vehicle, and in comprising a relative position estimation unit configured for: determining a plurality of respectively different information combinations, each of the information combinations comprising one of the travel locus/condition information sets generated by the host vehicle and one of the reception maps, calculating respective magnitudes of agreement degree of the information combinations, comparing the respective magnitudes of agreement degree with one another, and estimating a position of the host vehicle relative to a reference travel locus, with respect to a direction at right angles to the reference travel locus, based on results of the comparison; the reference travel locus comprising a travel locus previously traversed along the travel direction by the host vehicle or vehicle of the same type as the host vehicle when obtaining the travel locus/condition information constituting the reception maps. |
