Clock synchronization for IEEE 802.11 based wired-wireless hybrid networks using PTP

The current goal for real-time communication infrastructure in factory automation is to merge and balance the best of both worlds, i. e. the reliability of wired networks, and the flexibility of wireless technologies. Hybrid wired-wireless networks are proposed for establishing real-time communication infrastructures in factory automation. However, the provisioning of synchronized clocks is often taken for granted, and issues regarding the integration of wired and wireless synchronization are neglected. In this study, the requirements for providing clock synchronization for such networks are investigated for an IEEE 802.11 WLAN-based hybrid network with IEEE 1588 as the desired synchronization protocol. The paper also presents simulation and implementation results to assess the synchronization performance of WLAN-based hybrid networks.