sentences:  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.