Timing Recovery for IEEE 1588 Applications in Telecommunications

IEEE 1588 is being proposed as a solution to transport synchronization information within telecommunication networks, both for infrastructure use and for use in applications where time and frequency are required. The requirements of synchronization in these cases, however, are quite different from the traditional use of IEEE 1588 for synchronization in control and instrumentation applications. For successful deployment in communication applications, it is necessary to consider the unique aspects of telecom sync and the interrelation of these factors with timing recovery using IEEE 1588. This paper discusses the error considerations that must be applied toward timing recovery in packet-timing implementations, particularly those targeted toward telecom sync. A review of basic rate-recovery concepts is used to identify the various sources of error and their effects. Simulation and experimental results are used to illustrate the impact of different factors on the recovered timing.