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Two way time transfer results at NRL and USNOThe Naval Research Laboratory (NRL) has developed a two way time transfer modem system for the United States Naval Observatory (USNO). Two modems in conjunction with a pair of Very Small Aperture Terminal (VSAT) and a communication satellite can achieve sub nanosecond time transfer. This performance is demonstrated by the results of testing at and between NRL and USNO. The modems use Code Division Multiple Access (CDMA) methods to separate their signals through a single path in the satellite. Each modem transmitted a different Pseudo Random Noise (PRN) code and received the others PRN code. High precision time transfer is possible with two way methods because of reciprocity of many of the terms of the path and hardware delay between the two modems. The hardware description was given in a previous paper.
Document ID
Document Type
Conference Paper
Galysh, Ivan J.
(Naval Research Lab. Washington, DC, United States)
Landis, G. Paul
(Naval Research Lab. Washington, DC, United States)
Date Acquired
August 16, 2013
Publication Date
June 1, 1993
Publication Information
Publication: NASA. Goddard Space Flight Center, The 24th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting
Subject Category
Physics (General)
Accession Number
Distribution Limits
Work of the US Gov. Public Use Permitted.
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