Microsecond-Level Synchronization Solution for Grid-Edge Devices Utilizing Cellular Networks in GNSS-Challenged Areas

Abstract

This article presents a novel synchronization technique that utilizes cellular networks to deliver microsecond-level timing signals to grid-edge devices, offering a reliable timing solution in areas where Global Navigation Satellite System is challenged, such as indoors or urban canyons. First, the primary synchronization signal (PSS) from the cellular network is periodically sampled. The frequency of the timing signal is then precisely adjusted using a proportional–integral controller, based on the position of PSS within the sampling window. This adjustment process is continued until the position of PSS aligns consistently with its designated position in the radio frame, ensuring that the timing signal is synchronized with the cellular network. A test bench is developed using the B210 model of the Universal Software Radio Peripheral platform, and extensive tests are conducted in various environments. Experimental results demonstrate that the proposed method delivers stable timing signals with a timing error below $\pm 5$ $\mu$s to grid situational awareness devices in indoor scenarios.