Distributing Time and Frequency Information
Judah Levine · 2020
This chapter describes a number of methods that can be used to distribute time and frequency information with the goal of calibrating or synchronizing a local clock. The primary focus is on methods that use the signals from global navigation satellites – primarily the signals from the US GPS satellites. The accuracy claim should be supported by traceability documentation, which is also described in this chapter. There are a number of methods that are used to evaluate the channel delay or to remove its effect, and they are discussed. The time delay through the antenna and receiver is attenuated in the two-way method, and the delays at the two end stations will cancel exactly if they are equal. The chapter discusses the considerations that define each synchronization strategies, and then provides a number of examples based on real data. The basis for all synchronization strategies is the free-running stability of the local clock oscillator.