Delay-Phase Optimization for Hybrid Precoding in WideBand Massive MIMO System*

The ultra-wideband nature of terahertz (THz) communication introduces unique challenges, such as beam splitting and frequency-dependent steering vector mismatches, which can significantly degrade the performance of massive MIMO systems. This paper proposes a timedelay hybrid precoding architecture to mitigate the effects of beam squint and angular spread in THz wideband systems. By modeling the THz channel using both path-based and cluster-based approaches,the proposed architecture introduces frequency-dependent phase shiftsto align with the clustered channel characteristics. Extensive simulations validate the superiority of the proposed method, demonstrating a 12 percentage improvement in achievable data rates compared to conventional hybrid precoding methods under clustered channel conditions. Additionally, the proposed approach maintains over 90percantage of the theoretical maximum achievable rate, even in scenarios with high angular spread. The results highlight the efficiency of the proposed architecture in optimizing spectral efficiency and mitigating array gain loss, making it a promising solution for future 6G wireless networks.