でんし じょうほう つうしん がっかい ろんぶんし. B, つうしん (ISSN: 1344-4697)

Description

B - Abstracts of IEICE TRANSACTIONS on Communications (Japanese Edition) Vol.J93-B No.1 pp.43-52
Publication Date: 2010/01/01
Online ISSN: 1881-0209
Print ISSN: 1344-4697
Type of Manuscript: PAPER
Category:
Keyword:
frequency transfer, the Internet, FTTH, short term statistics, atomic clock,

Summary:
Many of Wireless communication systems and distributed measurement and control applications need accurate frequency. Even an atomic clock, often used as a standard frequency oscillator, needs frequency calibration. Because it has frequency drift, called as aging. We present a new frequency dissemination method via the Internet which can be used inside an building where GPS signal does not reach. Frequency difference shows clock speed. We measure one-way delay to compare two atomic clocks. The Internet traffic is not stable and the statistics of the one-way delay is not also stable. The presented method use short-time statistics of pseudo-delay which is addition of one-way delay and clock difference. A microscopic Typical pseudo-delay (uTP) is extracted from short-time periods with small dispersion. To evaluate proposed method, FTTH (Fiber to the home) is used as access line. We can get order of minus 11 accuracy for twe weeks average.