Hardware-based solution of precise time synchronization for Networked Control System

A hardware-based solution of precise time synchronization over Ethernet was proposed for Networked Control System (NCS). Using Field-programmable Gate Array (FPGA), hardware-based solution was designed for implementing time synchronization protocol defined in IEEE 1588. Timestamp capture, oscillator frequency compensation, time synchronization and etc., were all coded with Very High Speed Integrated Circuit Hardware Description Language (VHDL). Based on Kalman filter, time synchronization arithmetic was optimized to enhance the accuracy. The test results show that time accuracy reaches to sub-microsecond range, and the solution which makes system time synchronization easily is flexible and scalable for NCS and instruments.