Beyond Array-Specific Hybrid Beamforming: a Universal Shifted Codebook Set Framework

The increasing demand for high-capacity and energy-efficient wireless communications has made extreme massive Multiple Input Multiple Output (MIMO) a critical technology for 6G networks. Hybrid beamforming is essential to trade-off spectral efficiency and power consumption, yet existing solutions are typically array-specific. Additionally, most work focuses on single-polarized antenna systems, whereas dual-polarized arrays are widely used in practical deployments. This paper proposes a universal shifted codebook set-based hybrid beamforming framework for dual-polarized massive MIMO. The key lies in decoupling the array architecture impact from the hybrid beamforming optimization, transferring it into a designed shifted codebook set. This enables seamless adaptation across different hybrid array architectures without modifying core algorithm modules. Based on this framework, we develop two efficient algorithms: shifted-codebook orthogonal matching pursuit and shifted-codebook greedy grid-of-beam for joint and two-stage hybrid beamforming, respectively. Simulations using 3GPP dual-polarized channels show that our algorithms outperform the state-of-the-art solution, offering higher spectral efficiency and improved energy efficiency while maintaining flexibility for product evolution and MIMO hardware upgrades.