Perimeter surveillance radar
Perimeter surveillance radar (PSR) is a class of radar sensors that monitor activity surrounding or on critical infrastructure areas such as airports, seaports, military installations, national borders, refineries and other critical industry and the like. Such radars are characterized by their ability to detect movement at ground level of targets such as an individual walking or crawling towards a facility. Such radars typically have ranges of several hundred metres to over 10 kilometres. Alternate technologies include laser-based systems. These have the potential for very high target position accuracy, however they are less effective in the presence  of fog and other obscurants. Characteristics. PSR's usually have the following required characteristics: Characteristics of some perimeter surveillance radar systems: Challenges to PSR. Perimeter surveillance radars may operate in areas with high clutter levels. In the range of frequencies used almost all objects return some reflection from the radar, as does the ground itself. Foliage presents a particular problem as it is both a barrier to the radar energy, as well as an area in which it is difficult to detect a moving target due to the foliage being blown by the wind appearing as multiple moving targets. To  a degree, Doppler based radar can detect movement in such areas, as long as the component of movement velocity towards or away from the radar is significant enough to generate a signal that overcomes the foliage return signal. Radar does not have enough resolution to identify one person from another, so cannot be used as a substitute for CCTV. Many PSRs directly interface to control daylight or thermal cameras using a "slew to cue" system to overcome this problem. Total automation may be achieved if the camera uses analytics. PSR manufacturers. Perimeter surveillance radar makers include: Perimeter surveillance radar