Compact Surveillance Radar

Compact Surveillance Radar emits microwaves from a transmitter and detects any reflected microwaves. They are similar to microwave detectors but can detect the precise location of intruders in areas extending over hundreds of acres. With the capability of measuring range, angle, velocity, direction and size of the target, a CSR is able to pinpoint a precise GPS coordinate of an intruder. This target information is typically displayed on a map, user interface or situational awareness software that defines geographical alert zones or geofences with different types of actions initiated depending on time of day and other factors. CSR is commonly used to protect outside the fenceline of critical facilities such as electrical substations, power plants, dams and bridges.

Driveway Alarms

Driveway alarm systems can be tied into most security and automation systems. They are designed to alert home owners to unexpected visitors, intruders or deliveries arriving at the property. They come in magnetic and infra red motion sensing options. Driveway alarms can also be purchased in hard wired and wireless systems. They are common in rural security systems as well as for commercial applications.

E-field

This proximity system can be installed on building perimeters, fences, and walls. It also has the ability to be installed free standing on dedicated poles. The system uses an electromagnetic field generator powering one wire, with another sensing wire running parallel to it. Both wires run along the perimeter and are usually installed about 800 millimetres apart. The sensing wire is connected to a signal processor that analyses:

  • amplitude change (mass of intruder),
  • rate change (movement of intruder),
  • preset disturbance time (time the intruder is in the pattern).

These items define the characteristics of an intruder and when all three are detected simultaneously, an alarm signal is generated.

The barrier can provide protection from the ground to about 4 metres of altitude. It is usually configured in zones of about 200 metre lengths depending on the number of sensor wires installed.

  • advantage: concealed as a buried form.
  • disadvantage: expensive, short zones which mean more electronics (more money), high rate of false alarms as it cannot distinguish a cat from a human. In reality it does not work that well, as extreme weather causes false alarms.

Glass break detection The glass break detector may be used for internal perimeter building protection. Glass break acoustic detectors are mounted in close proximity to the glass panes and listen for sound frequencies associated with glass breaking.

Seismic glass break detectors, generally referred to as "shock sensors" are different in that they are installed on the glass pane. When glass breaks it produces specific shock frequencies which travel through the glass and often through the window frame and the surrounding walls and ceiling. Typically, the most intense frequencies generated are between 3 and 5 kHz, depending on the type of glass and the presence of a plastic interlayer. Seismic glass break detectors “feel” these shock frequencies and in turn generate an alarm condition.

Window foil is a less sophisticated, mostly outdated, detection method that involves gluing a thin strip of conducting foil on the inside of the glass and putting low-power electric current through it. Breaking the glass is practically guaranteed to tear the foil and break the circuit.