Timing Offset and Timing Stability for Dual-Clock Systems

Published

May 4, 2021

Author(s)

Joshua Kast, Jeanne Quimby, Jake Rezac, Stefania Romisch

Abstract

In this work, we describe a mathematical framework for evaluating timing offset and timing noise in channel sounders, based on a second-order deterministic model, and a stochastic metric based on the Allan Deviation. Using this framework, we analyze the timing offset and timing noise for a 1-6 GHz correlation-based channel sounder which uses rubidium clocks to synchronize the transmitter and receiver. We study timing behavior in three clock-distribution configurations. In the "untethered" configuration, the transmitter and receiver each have a rubidium clock, and no physical timing cable is connected between the clocks. In the "tethered" configuration, a coaxial cable synchronizes timing between the two separate clocks. Finally, a benchmark "single-clock" configuration is used where a single rubidium clock drives the transmitter and receiver. We analyze the experimental channel-sounder data for timing offset using a second-order clock model. Next, we perform a qualitative analysis of the timing noise processes using Time Deviation, a modified form of the Allan Deviation. From these analyses, we gain insight into the sources of timing offset and timing noise in our correlation-based channel sounder.

Citation

IEEE Antennas and Propagation Magazine

Pub Type

Journals

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Keywords

5G technology, channel sounder, millimeter-wave wireless communication, propagation channel, system timing, Time Allan Deviation, timing errors, timing noise, timing offset, wireless system

Citation

Kast, J. , Quimby, J. , Rezac, J. and Romisch, S. (2021), Timing Offset and Timing Stability for Dual-Clock Systems, IEEE Antennas and Propagation Magazine, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=929258 (Accessed October 8, 2025)