BDS/GPS Tens of Picoseconds Time Synchronization Method With Application to Communication Network
Wei Song, Dayu Yan, Chuang Shi, Fu Zheng, Caicong Wu, Guifei Jing, Yuzhuo Wang, Xiaolin Meng · IEEE Internet of Things Journal · 2025
Time synchronization is a critical requirement in sixth-generation (6G) communication systems and Internet of Things (IoT) applications. However, the standard timing services provided by global navigation satellite systems (GNSS) are increasingly unable to meet the growing demands for precision and stability in modern networks. The proposed system leverages a single-difference time transfer (SDPT) method to achieve tens of picoseconds precision, enabling effective clock disciplining for oven-controlled crystal oscillators (OCXO). A clock disciplining within a phase-locked loop (PLL) structure further optimizes the output of time and frequency signals, enhancing OCXO stability. Additionally, a differential precise time synchronization system (DPTSS) by the BeiDou navigation satellite system (BDS)/global positioning system (GPS) is developed to deliver high-precision time reference signals for communication networks. Experimental results demonstrate that the real-time 1 pulse-per-second (1PPS) interval achieved by the BDS/GPS time link is better than 0.1 ns, with long-term frequency stability reaching the$10{^{-}16 }$level. Furthermore, the proposed system achieves an 1PPS signal synchronization precision of 0.73 ns in communication networks, significantly outperforming the other state-of-the-art methods.