ABSTRACT
This chapter presents fundamentals of radar, and outlines the historical background, the theory, the signal environment, the radar equation, and applications. Radar is about using electromagnetic waves to detect the presence of objects and to extract as much information as possible from the interaction of electromagnetic waves with objects. A radar target is the object of interest that is embedded in noise and clutter together with interfering signals. Noise is a floor signal which limits the smallest signal that can be measured in the receiver. Radar is a measuring device that measures target’s range, range rate, direction, and reflected power. Because of imperfections in any measuring instrument, some amount of error will always be introduced. The errors of a radar are characterized by two performance parameters: resolution and accuracy. At the radar receiver, target echoes are contaminated with other unwanted echoes; therefore, a threshold decision is required for target detection.
