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Precise T and F intercomparison via VLF phase measurementsContinuous phase recording of the 16kHz transmission from GBR (UK) are being made and published midday phase data of GBR are received regularly from laboratories in the US, FGR, and UK. The local time scale (UTC, India), at the National Physical Laboratory in New Delhi, and those at the foreign laboratories are intercompared using the VLF phase data. A major factor which limits the accuracy of long term comparison is the seasonal variation in the VLF over delay over long paths. By taking into account the seasonal delay variations in a semiempirical way, the accuracy of time and frequency comparisons can be improved. Over a one year period, accuracy of a few parts in 10 to the 14th power in frequency and 1 to 2 micron sec in time were obtained. The relative frequency offset difference between UTC, (India) and UTC (PTB, Germany) of (7.0 + or - 0.1) x 10 to the -13 power agrees well with that obtained in a satellite experiment.
Document ID
19810018969
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Gupta, A. S. (National Physical Lab. New Delhi, India)
Goel, G. K. (National Physical Lab. New Delhi, India)
Mathur, B. S. (National Physical Lab. New Delhi, India)
Date Acquired
August 11, 2013
Publication Date
March 1, 1981
Publication Information
Publication: NASA. Goddard Space Flight Center Proc. of the 12th Ann. Precise Time and Time Interval Appl. and Planning Meeting
Subject Category
Instrumentation And Photography
Accession Number
81N27507
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle19810018929Collected WorksProceedings of the 12th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting
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