Abstract: An antenna device in a reading device has a main radiation direction and receives a signal transmitted by a transponder. An electronic assembly calculates a direction from the reading device to the transponder using the received signal. An orientation detector in the reading device, for example an electronic compass, detects an absolute orientation of the reading device with respect to an exterior region. While the main radiation direction of the antenna is pivoted in the region and the signal strength is measured, the orientation in the region is simultaneously detected. A correlation of the orientation that is detected at a point in time to the signal strength that is measured at the same point in time allows determination of the direction to the transponder because it can be assumed that the signal has a maximum when the main radiation direction points in the direction of the transponder.