Properties of ambiguity function of frequency diverse array radar

Frequency Diverse Array (FDA) radar has recently gained substantial interest among the researchers due to its unique range-angle-dependent beampattern in contrast to angle-dependent beampattern of phased-array radar. In the simplest form of FDA radar, a uniform inter-element frequency offset is applied across the aperture of uniform linear array of sensors. This offset may be small as compared to the carrier frequency or large, giving rise to different advantages. To investigate the range and Doppler resolution of a radar system, ambiguity function has been a traditional and effective tool. In this letter, the ambiguity function of FDA radar with small frequency offset has been formulated, and some important properties of the ambiguity function have been derived. These properties can help compare its performance with the other forms of radar.