The PicoTime™ is a low-cost, high-performance measurement test set. It features a cuttingedge 1ps resolution and an easy-to-use software application for performance analysis. Combined with the CNT-91 Frequency Counter/Analyzer, it enables very high resolution measurements of ADEV from 1ms and up, TIE, plus frequency
The system is designed to make a direct frequency measurement in comparison with an external 10 MHz frequency reference. Picotime is based on a heterodyne system using direct digital synthesizer (DDS) technology to allow measurements in the range of up to 30 MHz. The external 10 MHz reference divided by 2×107 is used to make time interval measurement each second.
Let us suppose that the aim of the setup is to measure the short time stability of a 10 MHz frequency clock with a resolution of few ps.
For this purpose, we can improve the resolution of the CNT-91, by adding the PicoTime as a RF front-end to the measurement system. Thereby, we get a signal of 1kHz with the behaviour of the original signal of 10 MHz. It is possible to say, that we have magnified the signal to measure, with a factor of 104, and therefore the error measured in the 1kHz signal is equivalent to 104 times the error on the original signal. In this way we have an ideal improvement of resolution of our measurement by this factor.