| 摘要 |
FIELD: physics. ^ SUBSTANCE: navigation device has a processor adapted to communicate with the memory unit and receive position information from the positioning device, and a memory unit adapted to contain a data base of speed traps which contains detection points and additional detection points of location of two-point speed traps. The additional detection point is associated with at least one of the stored detection points, wherein both are associated with the same two-point speed trap. Also, the navigation device is adapted to issue a warning when one of the detection points approaches, and issue a warning when the additional detection point approaches or has been passed. ^ EFFECT: warning when travelling through a monitored region, for example a two-point speed trap. ^ 19 cl, 5 dwg |
