An Optimization Approach for Carrier-to-interference Ratio Enhancement in Spaceborne Multibeam Antennas Via Multi-Point Generalized Eigenvalue Decomposition

This paper proposes a novel beamforming method based on generalized eigenvalue decomposition (GEVD) to address severe same-color interference in spaceborne multibeam antenna systems. By constructing distinct signal and interference subspaces through spatial smoothing, the approach optimizes weighting vectors to maximize edge-of-coverage gain while robustly suppressing side lobes. Simulations demonstrate that, compared to traditional analytical methods, this technique significantly improves edge gain by 2.26 dB, reduces interference area side-lobe levels by 5.58 dB, and enhances the carrier-to-interference (C/I) ratio by 7.92 dB, effectively boosting overall spectrum efficiency.