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arXiv · 2210.05764

A Sub-Picosecond Digital Clock Monitoring System

Rohith Saradhy·Erich Frahm·Eduardo B. S. Mendes·Roger Rusack
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Abstract

We describe a low-cost system designed to monitor wander in digital clocks with a precision of $\le$ 1 ps. With this system we have shown that it is possible to track phase variations at the sub-picosecond level by adding noise to a reference clock. As in many cases where a clock is part of a complex distribution network small changes in temperature and other effects can lead to small changes in the a clock's phase. As a further demonstration of the system, we have used it to measure the phase changes induced in optical signals in fibers.

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Rohith Saradhy, Erich Frahm, Eduardo B. S. Mendes, Roger Rusack. 2022-10-11. A Sub-Picosecond Digital Clock Monitoring System. https://doi.org/10.1088/1748-0221/18/01/t01003

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