Multisatellite Cooperative Antijamming Beamforming for LEO Systems Against Broadband Jamming

Abstract

Low Earth orbit (LEO) satellite communication systems suffer severe disruptions from broadband noise jamming. To tackle this challenge, this article proposes a lightweight multisatellite cooperative antijamming framework customized for the stringent hardware and computational limits of LEO platforms. The framework adopts Root-multiple signal classification (MUSIC) to achieve efficient local direction-of-arrival (DOA) estimation and reduce onboard computational burden, while fusing local DOA estimates via intersatellite links. Furthermore, a weighted least squares -based collaborative jammer localization method is developed using the fused DOA results, and the multiconstrained linearly constrained minimum variance beamforming is deployed with dynamically updated DOA estimates for real-time antijamming during LEO satellite motion. Simulations show that the proposed scheme, implemented with a per-satellite $2 \times 2$ antenna subarray and only 32 snapshots, achieves 30.71–60.82 dB broadband jamming suppression under low jamming-to-noise ratio conditions (0–10 dB), and outperforms the single-satellite Root-MUSIC and ST-DOAMatrix methods. Results validate that the cooperative strategy effectively balances local processing efficiency and information fusion accuracy, fully exploiting spatial diversity to enhance antijamming performance in dynamic LEO orbital scenarios.