HIDDEN OBJECT DETECTOR

摘要

A hidden object detector includes a transmission signal source generating a chirped signal whose instantaneous frequency changes linearly during a transmission period. A transmitter is driven by the signal source and transmits a radiating signal away from the detector toward an obstruction capable of hiding a hidden object. At least one receiver in close proximity to the transmitter receives a portion of radiation as reflected back toward the detector from the direction of the obstruction. A signal processing system estimates a signal strength and a time delay of the received signal, where the time delay is measured relative to an internal reference signal. The delay, or phase, information provides an estimation of the distance to the hidden object which is usable as a detection criteria. An indicator signal, usable to drive a user interface, is also generated that indicates the presence or absence of the hidden object.