A TWO-DIMENSIONAL LOW-SIDELOBE TRANSMIT BEAMPATTERN SYNTHESIS FOR LINEAR FREQUENCY DIVERSE ARRAY

Although phased-array beamforming has received much attention, it cannot effectively suppress the interferences that have the same direction angle but different ranges of the targets. More seriously, the targets may be submerged in the strong interferences and can not be identified. In this letter, we propose a range-dependent interference suppression via frequency diverse array (FDA) transmit beamforming based on convex optimization algorithm. The FDA uses a small frequency increment based on phased-array to provide a range-dependent beampattern, which thus offers a beamforming-based solution to suppress range-dependent interferences. The interference suppression performance as compared to phased-array is analyzed by examining the output signal-to-interference ratio (SIR) and signal-to-clutter ratio (SCR). Simulation results show that significant SIR and SCR performance improvements have been achieved by employing the proposed method.