Deceptive jamming discrimination based on range-angle localization of a frequency diverse array

We propose a method to suppress deceptive jamming by frequency diverse array (FDA) in radar electronic countermeasure environments. FDA offers a new range-angle-dependent beam pattern through a small frequency increment across elements. Due to the coupling between the angle and range, a mismatch between the test angle and physical angle occurs when the slant range on which the beam focuses is not equal to the slant range of the real target. In addition, the range of the target can be extracted by sum-difference beam except for time-delay testing, because the beam provides a range resolution in the FDA that cannot be deceived by traditional deceptive jamming. A strategy of using FDA to transmit two pulses with zero and nonzero frequency increments, respectively, is proposed to ensure that the angle of a target can be obtained by FDA. Moreover, the localization performance is examined by analyzing the Cramer-Rao lower bound and detection probability. Effectiveness of the proposed method is confirmed by simulation results.