SYMMETRICOM TIME-SCALE SYSTEM |
|---|
| Timothy Erickson, Venkatesan Ramakrishnan, Samuel R. Stein |
- Abstract:
- Symmetricom has developed a Time Scale System that incorporates advanced measurement, sign al processing, and algorithmic techniques to provide an automated solution suitable for a national time scale. The total system includes two redundant time scale sub-systems with automatic output switching in case of a failure. Each time scale creates a real-time UTC(lab) output including such signals as 1 PPS, IRIG time codes, serial time code, 5 and 10 MHz, NTP, and PTP. The base system supports up to 6 local clocks, which may be either cesium standards or hydrogen masers and additional remote clocks. Input switching of the clocks is used so that failure of an individual clock does not cause a failure of the UTC (lab) output. The time scales use the KAS-2 algorithm to create a free time scale called TA (lab) [1], [2], [3]. A coordinated paper time scale is formed by steering relative to the free time scale using measurements from either the GNSS receiver or Circular-T. The UTC (lab) output is generated by steering a synthesizer to the coordinated time scale. The paper presents the overall system design as well as details of the time-scale algorithm, robustness algorithms, and steering algorithms. Performance data are presented.
- Keywords:
- time scale, frequency stability, UTC, Kalman filter
- Download:
- IMEKO-TC4-2011-010.pdf
- DOI:
- -
- Event details
- IMEKO TC:
- TC4
- Event name:
- TC4 Symposium 2011
- Title:
XVIIIth IMEKO TC4 International Symposium on Measurement of Electrical Quantities (part of Metrologia2011, together with IX International Congress on Electrical Metrology - IX SEMETRO)
- Place:
- Natal, BRAZIL
- Time:
- 27 September 2011 - 30 September 2011