Optimal Frequency Diverse Subarray Design With Cramér-Rao Lower Bound Minimization

This letter proposes an optimal subarray design strategy for frequency diverse array (FDA) radar target localization via Cramér-Rao lower bound (CRLB) minimization. To decouple the range and angle response of targets, we divide the FDA transmit array elements into multiple subarrays. For a given number of array elements and subarrays, the optimal array division and frequency increments design strategies are formulated as a constrained CRLB minimization problem. Then it is converted into an unconstrained optimization problem and further resolved by iteratively utilizing the Nelder-Mead algorithm. Numerical results show that, under the same condition, FDA radar localization performance is significantly improved by employing the CRLB minimization strategy.