Passive referring to the fact that the systems does not need external energy to function. These systems are triggered when a glass window or door is broken. In the following article I will take a look at the various types of outdoor security systems and explain the physics of concepts of how the security systems work. You may remember these as depicted in many spy or action movies. These systems admit ultra sonic sound that in undetectable by humans. I will specifically be looking at the following types of outdoor home security systems: Vibration Sensors, Magnetic Field Detection, E-Field, Microwave Barriers, Microphonic Systems, Taut Wire Fence Systems, Fibre Optic Cable, H-FieldPassive Infared Systems/DetectorsPIR or Passive Infrared Detectors are one of the most common types of detectors found in small business and house security systems. Take in mind that these types of systems are considered obsolete by many security companies and are not regularly used. Ultrasonic systems work on the Doppler shift and can detect movement by a change in the frequency.Microwave SystemsMicrowave alarm systems work by emitting microwaves from a transmitter and measures reflections and beam intensity using a receiver.
Microwave alarm systems are often combined with a PIR detector to reduce false alarms.. These systems detect the breaking glass through acoustic waves or shock frequencies.Ultrasonic DetectorsUltrasonic systems work on the physics of sound.Home dowellsonic Security systems can be broken down into two main categories indoor systems and outdoor security systems.
Passive Infared Detectors function by begin able to tell when there is a change in the temperature in a giving zone, it accomplishes this by first measuring the static temperature of a zone then monitors the space for a change in temperature.Glass Break DetectorsGlass break detector used for internal perimeter building protection.Photo-Electric BeamsPhoto-electric alarm systems transmit either visible or infrared beams across an area, setting a so called tripwire, and when the beams are obstructed it will trigger an alarm system