Digital Beamforming Method Based on Space-based Distributed Array

Beamforming technology has been widely applied in radar systems and related fields. To overcome the limitations of traditional fixed arrays, such as restricted electrical aperture and high vulnerability to enemy detection, a digital beamforming method based on a space-based distributed array is proposed. A joint optimization cost function is established for the array element positions and the antenna array weight vectors, aiming to achieve a unit response in the target direction and null responses in the jamming directions while simultaneously minimizing the sidelobe level. The Lawson criterion is employed to transform the original minimax problem into a tractable weighted optimization form. Based on this formulation, an alternating iterative optimization strategy is adopted, in which the antenna array weight vector and the array element positions are updated sequentially and repeatedly until convergence. Simulation results demonstrate that the proposed method effectively reduces the peak sidelobe level (PSLL), suppresses strong jamming, and forms a high-performance beam pattern, indicating that the detection performance of space-based distributed arrays can be significantly enhanced.