To provide a highly sensitive device for surveying a resonance body maker capable of using a small and inexpensive resonance body marker having an LC resonance circuit formed.
This device for surveying the resonance body marker comprises a transmitting part 2 for intermittently transmitting a transmitting signal at a specified frequency to the resonance body marker 20 through a variation of magnetic field with time, and also comprises a receiving part 3 for receiving a responding signal, sent by the resonance body marker 20 with responding to the transmitting signal, through the variation of the magnetic field with time so as to survey the resonance body marker 20 based on the receiving signal. The transmitting part 2 comprises a transmitting side local oscillator 6 for sweeping the frequency of the transmitting signal stepwise within a specified frequency range including resonance frequency of the resonance body marker 20 while repeating a series of the sweeping at a specified repeating period. The receiving part 3 comprises a band-pass filter 13 with a pass band including a repeating frequency obtained as an inverse of the repeating period of the transmitting side local oscillator 6.
MORIZAKI HIROYASU
KUBOTA KENJI
FUJI TECOM INC
MIYAKE KK