Patent ID: 8408553
Filing Date: 2013-04-02
Classification: A63B

Abstract:
1. A system comprising a movable object, radio wave emitter means arranged in the movable object, stationary exciter means arranged for exciting said radio wave emitter means, stationary receiver means for receiving radio waves from the radio wave emitter means and for providing an output accordingly, a plurality of substantially closed first antenna circuits arranged along a periphery of a flat target plane, each of the plurality of substantially closed first antenna circuit comprising two substantially parallel conductors extending substantially parallel to said periphery of the target plane, one of the two substantially parallel conductors being arranged on a first side of the flat target plane and the other of the two conductors being arranged on a second opposing side of the flat target plane, each of the two substantially parallel conductors being arranged a substantially similar distance in a direction perpendicularly to the flat target plane, wherein said plurality of first antenna circuits constitutes one of said stationary exciter means and said stationary receiver means, and data processing means to receive and process said output together with a predetermined set of conditions and providing a resulting output if the set of conditions are fulfilled so as to determine whether the movable object passes the flat target plane.