Beam Pattern Synthesis for an FDA Radar with Hamming Window-Based Nonuniform Frequency Offset

A frequency diverse array (FDA) with uniform inter-element frequency offset generates an “S-shaped” beam pattern with maxima at multiple range and angle values. This property allows a number of reflectors positioned at any of the maxima to interfere with the target-returns, thus weakening the signal-to-interference-plus-noise ratio. In this letter, a uniformly spaced symmetric FDA with Hamming window-based tapering interelement frequency offsets has been proposed. The proposed design produces a single maximum beam pattern toward the desired range and angle values. This approach is mathematically analyzed and verified by numerical results. Moreover, it outperforms the existing forms of FDA with uniform interelement offset, e.g., conventional FDA, as well as the FDA with nonuniform interelement offset, e.g., Log-FDA in terms of side-lobe suppression and transmit energy focusing.