ELECTROMAGNETIC WAVE MARKER AND ELECTROMAGNETIC WAVE MARKER SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an electromagnetic wave marker which can be set in various structural roads including an iron bridge by establishing both improvement of corrosion resistance and reduction of thickness. SOLUTION: This electromagnetic marker is provided with an almost bar- shaped receiving antenna 8 for receiving an electromagnetic wave, a frequency converting circuit 9 connected to the receiving antenna for multiplying the frequency of the electromagnetic wave, an almost disc-shaped transmitting antenna 10 for transmitting the electromagnetic wave with the frequency multiplied by the frequency converting circuit, a non-magnetic body case 11 for arranging and housing the receiving antenna and the transmitting antenna so that the electromagnetic wave to be received and the electromagnetic wave to be transmitted can be made orthogonal, and an electromagnetic wave reflector 12 arranged at the lower part of the non-magnetic body case for reflecting the electromagnetic wave to the transmitting direction. The transmitting antenna transmits the electromagnetic wave with the multiplied frequency to a marker detecting device, and the electromagnetic wave reflector reflects the electromagnetic wave from the transmitting antenna in the transmitting direction.