Method and apparatus for detecting moving objects, particularly intrusions

摘要

A method and apparatus for detecting movement of an infrared-radiating object within a monitored space is provided. The method of includes exposing the monitored space to a passive infrared sensor having a first sensor element generating a first polarity signal when its field of view senses an infrared-radiating moving object, and a second sensor element generating a second polarity signal when its field of view senses an infrared-radiating moving object and determining the direction of movement of the detected object from the relative sequential order of the first and second polarity signals, for example for detecting intrusions in the monitored space to determine whether the movement direction is a hostile direction or a friendly direction.