Beam split is a critical challenge in wideband THz massive MIMO systems, arising from frequency-dependent beam misalignment that degrades communication performance, particularly in scenarios with narrow beamwidths and large arrays. This work proposes an angular-based hybrid beamforming framework that leverages angular spread to mitigate the beam split effect. Instead of relying on precise angular spread modeling, we utilize coarse angular information to guide the design of subcarrier-specific beams, effectively reducing misalignment across subcarriers. By broadening the effective beamwidth through angular spread, the proposed method enhances user coverage and alleviates beam split without requiring complex time-delay units or hardware-intensive solutions. Simulation results demonstrate that the proposed approach achieves significant improvements in spectral efficiency and beamforming accuracy while maintaining low computational and hardware complexity. This work provides a practical and efficient solution for addressing beam split in next-generation wideband THz communication systems.

翻译：波束分裂是宽带太赫兹大规模MIMO系统中的关键挑战，其源于频率相关的波束失准，导致通信性能下降，尤其在窄波束宽度和大规模阵列场景中更为显著。本文提出一种基于角度的混合波束成形框架，利用角度扩展来缓解波束分裂效应。该方法不依赖于精确的角度扩展建模，而是利用粗略的角度信息指导设计针对各子载波的波束，从而有效减少子载波间的失准。通过角度扩展拓宽有效波束宽度，所提方法增强了用户覆盖范围并缓解了波束分裂，且无需复杂的时延单元或硬件密集型解决方案。仿真结果表明，所提方法在保持低计算与硬件复杂度的同时，实现了频谱效率和波束成形精度的显著提升。本研究为应对下一代宽带太赫兹通信系统中的波束分裂问题提供了一种实用且高效的解决方案。