Wide Area Wireless Network Synchronization Using Locata

Abstract

Many critical modern systems such as 4G mobile phone networks, banking, and electricity grids demand highaccuracy time and frequency stability across specified areas. In fact, precise network synchronization is critical for nearly all digital networks, and more stringent network stability requirements are expected to emerge as the user base for these applications continues to grow. To date, the preferred method to achieve this performance is via synchronization from the Global Positioning System (GPS). However, the vulnerability of GPS signals remains a growing concern among industry experts, and many are actively seeking alternative means of providing precise time transfer and frequency stability across wide areas. Previous technical papers have reported that Locata Corporation’s radio-based Position, Navigation, and Time (PNT) technology—which uses a patented “TimeLoc” process—enables network synchronization at the nanosecond level. Furthermore, they also show that Locata’s network time can be aligned to external references, such as GPS [1] or an atomic clock [2], providing exceptional time transfer and frequency coherence across wide rural areas. These results suggest that Locata could also be used to provide comparable performance across large urban areas. This paper details experiments conducted by the United States Naval Observatory (USNO) in Washington, DC which investigate the frequency stability of Locata networks (LocataNets) under multiple network configurations in urban environments. Details include specific test parameters and equipment configuration used to determine frequency synchronization across tested LocataNets. The paper further discusses how the Locata transmission signal can be extended—by “cascading” TimeLoc from one Locata transceiver to another—to cover substantially larger areas as required for user applications extending over a wide region. These USNO demonstrations confirm earlier published results and provide additional independent insight into the frequency synchronization capability of Locata’s TimeLoc process. For local areas ranging from small campuses to city-wide user situations, TimeLoc technology offers a relatively easy means of supporting exceptionally high precision time and frequency distribution over broadcast areas.