Patent · US Expired

Signal processing for object detection system

US6243036A · kind A · utility

37Cited by
49References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 2, 1999
Grant dateJun 5, 2001
Priority date
Expiry dateJul 2, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S7/2883
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Methods and apparatus for detecting objects are disclosed. In one embodiment of the invention, a person entering a secured or "Safe Zone.TM." is illuminated with low-power polarized radio waves. Differently polarized waves which are reflected back from the person are collected and measured. In a preferred embodiment of the invention, concealed weapons are detected by calculating the difference of a pair of differences between levels of different polarized reflected energy in the time domain, and by using signal processing methods and apparatus to improve the reliability of the detection process. Alternative embodiments of the invention may be used to detect a wide variety of objects other than concealed firearms. The invention may be used for inventory control or to thwart shoplifting.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.