Digital Frequency Detecting Device for Mobile Methane Frequency Standard

Abstract

. Utilization of methane optical frequency standard is promising for precision frequency measurements, in particular, it is a possible future mobile (and on-board) frequency standard with stability of 5 · 10 − 15 –5 · 10 − 16 , which will be used in frequency-time segment of GNS GLONASS. This paper deals with development of a digital frequency detector, designed to increase the methane standard short-term frequency stability. Accuracy of digital frequency counting algorithms is calculated. A numerical simulation of programmable logic device operation is conducted, which confirms the operability of a single channel synchronous-frequency detector with Allan variance of 1,4 · 10 − 13 per 1 s, and also provides a technology to increase the accuracy of the counting, allowing one to measure the Allan variance at 5,6 · 10 − 16 per 1 s.