An Enhanced IEEE 1588 Time Synchronization Algorithm for Asymmetric Communication Link using Block Burst Transmission

IEEE 1588 is a standard to synchronize independent clocks running on separate nodes of a distributed measurement and control system. In IP based cellular network, it is considered as a key technology to synchronize base stations. Especially, interests for the low-cost and very-small home cellular base station called the Femtocell is increasing, and it is connected to the cellular core network using an asymmetric communication link such as xDSL. However, the conventional IEEE 1588 synchronization algorithm assumes symmetrical links, and makes errors for asymmetric links for the calculation of the time difference between the master clock (a clock source) and the slave clock (a clock consumer). We propose an enhanced synchronization algorithm to calculate the asymmetric ratio of the communication link, and the proposed algorithm enhances an accuracy of the time synchronization.