Wide-Area Portal Metal Detector

Reference#: P02273

There exists a need for metal detection systems for screening people for metal weapons such as guns and knives. Conventional metal detectors require people to walk through a small portal that has an electromagnetic induction (EMI) metal detector. Typically, only one person can walk through a metal detector at a time. This creates a "choke" point and a line typically forms. For large sporting events, subways and anywhere that large crowds gather and must be screened, the use of portable type metal detectors create problems.

Researchers at the Johns Hopkins Applied Physics Laboratory have developed and are in the process of patenting a large magnetic field transmitter that is composed of a series of loops enclosing a passage way where people walk through; an array of magnetic field receivers located in the floor; a second optional magnetic field receiver array is located in the ceiling, and; a first and second camera located such that the area enclosed by the transmitter can be seen by the cameras. The transmitter, magnetic field receivers and cameras are connected to a data collection and control system (DCCS). The magnetic field receivers could be other magnetic field sensors such as magnetoresistors or flux gate sensors. The loop nature of the transmitter encloses the passageway. Multiple detectors can be grouped together to cover large areas and track people determined to have a high metal content.

Dr. G. R. Jacobovitz
Phone: (443) 778-9899