Patent ID: 9665749
Date: 2017-05-30
CPC Classifications: G06K,G07C,H02J

Claim:
1. A system comprising: a first resonant circuit including a first coil and a first resonant capacitor interconnected by a first node; a second resonant circuit including a second coil and a second resonant capacitor interconnected by a second node; a third resonant circuit including a third coil and a third resonant capacitor interconnected by a third node; a passive transponder coupled to the first, second and third resonant circuits, the passive transponder including: a first attenuator coupled to the first resonant circuit, the first attenuator operable to adjust a first bandwidth of the first resonant circuit; a second attenuator coupled to the second resonant circuit, the second attenuator operable to adjust a second bandwidth of the second resonant circuit; a third attenuator coupled to the third resonant circuit, the third attenuator operable to adjust a third bandwidth of the third resonant circuit; and a control circuit operable to control the first, second and third attenuators.