Patent ID: 8781772
Filing Date: 2014-07-15
Classification: G01R,G01V

Abstract:
1. A detection apparatus comprising: a transmitter configured to generate a detection signal; a coil assembly comprising a transmit coil coupled to said transmitter and configured to transmit the detection signal toward an object to be detected, with the object to be detected emitting a target signal in response to the transmitted detection signal, and a single receive coil adjacent said transmit coil and configured to receive the target signal emitted from the object along with an undesired coupling signal from said transmit coil; a matching network coupled to said transmitter and configured to generate an adjusted detection signal by adjusting a profile of the detection signal to match a profile of the undesired coupling signal; wherein the matching network comprises an amplitude stage coupled to a filter stage; and an output stage having a first input coupled to said single receive coil to receive the target signal and the undesired coupling signal, and a second input coupled to said matching network to receive the adjusted transmit signal, and configured to subtract the adjusted detection signal from the target signal and the undesired coupling signal so that the target signal remains.