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Clocks, Time Error, and Noise

By Shahid Ajmeri, Dennis Hagarty, Anshul Tanwar.
Sample Chapter is provided courtesy of Cisco Press.
Date: Jan 8, 2022.

Chapter Information

Chapter Description

In the world of electronics, the term clock refers to a microchip that generates a clock signal, which is used to regulate the timing and speed of the components on a circuit board. This sample chapter from Synchronizing 5G Mobile Networks explains the different metrics used to quantify time error and how to measure them.

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References in This Chapter

Open Circuit. “16Mhz Crystal Oscillator HC-49s.” Open Circuit. Picture. https://opencircuit.shop/Product/16MHz-Crystal-Oscillator-HC-49S

The International Telecommunication Union Telecommunication Standardization Sector (ITU-T).

“G.781: Synchronization layer functions for frequency synchronization based on the physical layer.” ITU-T Recommendation, 2020. http://handle.itu.int/11.1002/1000/14240
“G.810: Definitions and terminology for synchronization networks.” ITU-T Recommendation, 1996. http://handle.itu.int/11.1002/1000/3713
“G.811: Timing characteristics of primary reference clocks.” ITU-T Recommendation, 1997. http://handle.itu.int/11.1002/1000/4197
“G.812: Timing requirements of slave clocks suitable for use as node clocks in synchronization networks.” ITU-T Recommendation, 2004. http://handle.itu.int/11.1002/1000/7335
“G.813: Timing characteristics of SDH equipment slave clocks (SEC).” ITU-T Recommendation, 2003. http://handle.itu.int/11.1002/1000/6268
“G.8261: Timing and synchronization aspects in packet networks.” ITU-T Recommendation, Amendment 1, 2020. http://handle.itu.int/11.1002/1000/14207
“G.8262: Timing characteristics of a synchronous equipment slave clock.” ITU-T Recommendation, Amendment 1, 2020. http://handle.itu.int/11.1002/1000/14208
“G.8262.1: Timing characteristics of an enhanced synchronous equipment slave clock.” ITU-T Recommendation, Amendment 1, 2019. http://handle.itu.int/11.1002/1000/14011

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