Abstract: Conventional radar with phased-array antenna can only generate angle-dependent beam patterns. While recent proposed frequency diverse array (FDA) can generate beam patterns associated with angle, range and time. Based on the technology of FDA, we propose an optimal precoder and frequency offsets for FDA to lower the interference of FDA radar to other radio systems by maximizing the received signal-noise-ratio. The design of FDA precoder makes its beam pattern as an isolated point in angle-range domain, while the proposed optimization algorithm based on a reconstructed gradient descent method, wherein the step size is obtained by backtracking line search method. Numerical simulation shows that the proposed method can generate a point beam pattern at the target and the algorithm can converge within 10 iterations. Therefore, the proposed method can effectively reduce the interference in angle-range domain.