ABSTRACT
Continuous wave (CW) radar employs a transmitter which is on all or most of the time. Unmodulated CW radar is very simple and is able to detect the Doppler-frequency shift in the return signal from a target, which has a component of motion toward or away from the transmitter. While such a radar cannot measure range, it is used widely in applications such as police radars, motion detectors, burglar alarms, proximity fuzes for projectiles or missiles, illuminators for semi-active missile guidance systems (such as the Hawk surface-to-air missile), and scatterometers (used to measure the scattering properties of targets or clutter such as terrain surfaces) (Komarov et al., 2003; Nathanson, 1991; Pace, 2003; Saunders, 1990; Ulaby and Elachi, 1990).
