All our sensors use some type of ‘bucking’ to prevent the high power transmitter field from overwhelming the sensitive receiver input(s). It can be performed by using multiple transmit or receive coils.
In a GEM-3 configuration, the transmitter coil also has a separate ‘bucking’ section. The bucking section wraps around the receive coil to create a field which is equal but opposite to the main transmit field. The fields combine at the receiver coil to cancel out the transmit signal.
Directional GEM-5 and GEM-5 Array
In a GEM-5 configuration, receiver coils are used in pairs, above and below the plane of the transmitter coil. The signal from the upper receiver coil is subtracted from the lower receiver coil to achieve transmitter bucking. Because of the response of the sensor is directional, it is useful in eliminating ambient noise, as well as reducing the influence of targets to the side. In an array configuration, it combines the finer resolution of the smaller receive coils with the higher power and greater coverage of a large transmit area.