Impact of Different Backgrounds on Thermal Infrared IDS Performance

The performance of a passive thermal infrared IDS (intrusion detection system) employed in an exterior security application can be significantly impacted by the synergistic effects of the local background and weather. As reported by Peck1, these effects can lead to nuisance alarms resulting from radiance fluctuations in the background. They can also lead to missed intrusion detections due to inadequate thermal contrasts between the intruder and background. It is important to identify and to quantify the environmental scenarios which pose such risks to an infrared IDS. This paper describes, through the use of a model presented at last year's INMM annual meeting and a recently developed intruder thermal model, how several different background types affect the ability of a specific passive infrared IDS to detect intruders. The issues discussed and problems identified apply to passive infrared IDSs in general, and not just to the specific system examined.