Radars are electronic systems that can detect and track objects. They can provide a highly accurate measurement of the distance, velocity and direction of the detected objects. In principle, every radar system (a) transmits electromagnetic energy to search for objects in a specific volume in space (b) detects the energy reflected from objects in that volume (c) measures the time between the two events, and (d) ultimately provides estimates of range, amplitude and velocity of the objects based on the detected energy and measured time. Several other conventional systems, including infrared and video sensors, have typically been used to perform the above functions, but radars have a significant advantage of being highly immune to environmental and weather conditions . With technological advances leading to inexpensive radars, they are well-poised to replace existing low-functionality systems.