Modern systems use a variety of sensing techniques
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( time-domain reflectometry or accelerometers , for example ) and provide highly useful features like environmental compensation , precision ranging , cut immunity , and low-voltage power over sensor cables .
Fences may also be protected by other sensors , such as active IR or buried RF .
While very different technologies , both are used to generate invisible detection walls or fields , typically on the inside of the perimeter .
Active IR is low cost but only works in straight lines , while buried RF requires a clear area with good drainage .
Being installed on the protected side of the perimeter means that when an alarm does occur , the likelihood of the event being a legitimate security concern is very high .
Intelligent lighting with integrated intrusion detection capabilities is new in the security market
May 2018 Edition
.
Installed on the fence , LED-based luminaires provide uniform , wide-spectrum illumination targeted along the fence line while embedded accelerometers detect any
attempts to breach the fence .
In addition to having similar advantages to those of other fence-mounted sensors , intelligent lighting enhances the video quality of the cameras and acts as an immediate deterrent by illuminating the fence whenever an intrusion attempt is detected .
Intrusion attempts can also be detected via video analytics by using either virtual tripwires defined along the fence or area masks .
Entry-level analytics use simple motion detection while more advanced analytics use sophisticated algorithms that detect and classify the presence of people , vehicles , and objects .
Video footage of a person being tracked as they approach the fence . In this scenario , a PTZ camera can be directed towards the potential intruder before an actual intrusion attempt is made .
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