Metal detector system having multiple, adjustable transmitter and receiver antennas
AssigneeFederal Labs Systems LP
InventorsGranville T. Conway, Karl E. Geisel, Dennis M. Cunningham
Life of this patent
Estimating the term…
Abstract
A metal detector system includes two transmitter-receiver antenna pairs supported by respective side panels of a portal. The relative positions of an adjacent transmitter antenna and receiver antenna within an antenna pair may be adjusted to calibrate the antennas, such as by crossing adjacent antennas or by increasing the distance between adjacent antennas.
Claims24
A metal detector system comprising:
- a first planar surface;
- a second planar surface opposite said first planar surface to define a passage therebetween;
- a first transmitter antenna adjustably supported on said first planar surface for transmitting a first signal for detecting a metal object in said passage;
- a first receiver antenna adjustably supported on said second planar surface in a position opposite to a position of said first transmitter antenna for receiving said first signal from said first transmitter antenna and outputting a third signal in response to said first signal and a fourth signal in response to detection of a metal object in said passage;
- a second transmitter antenna adjustably supported on said second planar surface for transmitting a second signal for detecting a metal object in said passage;
- a second receiver antenna adjustably supported on said first planar surface in a position opposite to a position of said second transmitter antenna for receiving said second signal from said second transmitter antenna and outputting a fifth signal in response to said second signal and a sixth signal in response to detection of a metal object in said passage;
- said position of said first receiver antenna relative to said position of said second transmitter antenna on said second planar surface being adjustable to prevent said output signals of said first receiver antenna from being based on said second signal from said second transmitter antenna, and said position of said second receiver antenna relative to said position of said first transmitter antenna on said first planar surface being adjustable to prevent said output signal of said second receiver antenna from being based on said first signal from said first transmitter antenna.
A metal detector system comprising:
- a first planar surface;
- a second planar surface opposite said first planar surface to define a passage therebetween;
- a first transmitter antenna adjustably supported on said first planar surface for transmitting a first signal for detecting a metal object in said passage;
- a first receiver antenna adjustably supported on said second planar surface in a position opposite to a position of said first transmitter antenna for receiving said first signal from said first transmitter antenna and outputting a third signal in response to said first signal and a fourth signal in response to detection of a metal object in said passage;
- a second transmitter antenna adjustably supported on said second planar surface for transmitting a second signal for detecting a metal object in said passage;
- a second receiver antenna adjustably supported on said first planar surface in a position opposite to a position of said second transmitter antenna for receiving said second signal from said second transmitter antenna and outputting a fifth signal in response to said second signal and a sixth signal in response to detection of a metal object in said passage;
- and
- a metal shield adjustably positioned to cover said antennas and to prevent said output signals of said first receiver antenna from being based on said second signal from said second transmitter antenna and to prevent said output signals of said second receiver antenna from being based on said first signal from said first transmitter antenna.
A method of calibrating a metal detector having a first transmitter antenna on a first side of a portal for transmitting a first signal, a second transmitter antenna on a second side of the portal opposite the first side for transmitting a second signal, a first receiver antenna on the second side of the portal opposite the first transmitter antenna for receiving the first signal from the first transmitter antenna, and a second receiver antenna on the first side of the portal opposite the second transmitter antenna for receiving the second signal from the second transmitter antenna, comprising the steps of:
- adjusting the position of the first receiver antenna relative to the position of the second transmitter antenna for preventing an output signal of the first receiver antenna from being based on the second signal from the second transmitter antenna;
- and
- correspondingly adjusting the position of the second receiver antenna relative to the position of the first transmitter antenna for preventing an output signal of the second receiver antenna from being based on the first signal from the first transmitter antenna.
A method of calibrating a metal detector having a first plurality of first transmitter antennas on a first side of a portal for transmitting a first plurality of first signals, a second plurality of second transmitter antennas on a second side of the portal opposite the first side for transmitting a second plurality of second signals, a first plurality of first receiver antennas on the second side of the portal opposite the first transmitter antennas for receiving the first signals from the first transmitter antennas, and a second plurality of second receiver antennas on the first side of the portal opposite the second transmitter antennas for receiving the second signals from the second transmitter antennas, comprising the steps of:
- adjusting the position of each of the first receiver antennas relative to the position of each of the second transmitter antennas for preventing output signals of the first receiver antennas from being based on the second signals from the second transmitter antennas;
- and
- correspondingly adjusting the position of each of the second receiver antennas relative to the position of each of the first transmitter antennas for preventing output signals of the second receiver antennas from being based on the first signals from the first transmitter antennas.
A metal detector system comprising:
- a first planar surface;
- a second planar surface opposite said first planar surface to define a passage therebetween;
- a first transmitter antenna adjustably supported on said first planar surface for transmitting a first signal for detecting a metal object in said passage;
- a first receiver antenna adjustably supported on said second planar surface in a position opposite to a position of said first transmitter antenna for receiving said first signal from said first transmitter antenna and outputting a third signal in response to said first signal and a fourth signal in response to detection of a metal object in said passage;
- a second transmitter antenna adjustably supported on said second planar surface for transmitting a second signal for detecting a metal object in said passage;
- a second receiver antenna adjustably supported on said first planar surface in a position opposite to a position of said second transmitter antenna for receiving said second signal from said second transmitter antenna and outputting a fifth signal in response to said second signal and a sixth signal in response to detection of a metal object in said passage;
- said position of said first receiver antenna relative to said position of said second transmitter antenna on said second planar surface being adjustable to prevent said output signals of said first receiver antenna from being based on said second signal from said second transmitter antenna, and said position of said second receiver antenna relative to said position of said first transmitter antenna on said first planar surface being adjustable to prevent said output signal of said second receiver antenna from being based on said first signal from said first transmitter antenna;
- wherein said first receiver antenna and said second transmitter antenna are of elongated rectangular shape and are crossed at a predetermined angle, and said second receiver antenna and said first transmitter antenna are of elongated rectangular shape and are crossed at said predetermined angle.
Dependencies are inferred from the claim text.