Abstract:
Sensors positioned in power transmission systems with tubular enclosures have radio interrogation capabilities. The radio antenna assigned to a sensor is a planar antenna with a radiating element and a conductive baseplate, with the radiating element being designed as a reed that is provided in a self-supporting manner in a recess in the baseplate and is short-circuited to the baseplate at one end. This forms a quarter-wave antenna which can be tuned by using a metal resonating member with a U-shaped cross-section and can be combined with a surface-wave sensor.