Patent attributes
The invention relates to the methods and systems for remotely detecting metal items, for example, weapons, concealed in cloths or belongings and may be used in security complexes. The proposed system contains a phased antenna array 1 radiating a continuous frequency-modulated ultra high or super high frequency signal and scanning a controlled space, a receiver 2 of reflected signals, a processor 3, a display 4, and a video camera 5. The processor 3 detects a potentially threatening metal item during any scanning period other than the initial period if one of the two comparison conditions holds for some radiation direction: Ai>A0+Δ or Ai<A0−Δ where Ai is the code of the signal amplitude at the output of the receiver 2 of the reflected signal during any scanning period following the initial period for some radiation direction; A0 is the code of the signal amplitude at the same output for the same direction of radiation during the initial scanning period when no potentially threatening metal items are allowed in the scanning sector, and Δ>0 is the tolerance of the deviation of the code A0 taking into account permissible changes in the reflected signal. Advantages of the invention: extension of the range of permissible distances to detected metal items, increased noise immunity, simplified operator activities, and increased scanning rate and reliability.
