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A Proposed Time Transfer Experiment between the USA and the South PacificThis paper describes the concept, architecture and preliminary details of an experiment directctowards providing continuous Ultra High Precision (UHP) time transfer between Washington, DC;
Salisbury, SA Australia; Orroral Valley, ACT Australia; arid Lower Hutt, New Zealand. It further
describes a proposed method of distributing UTC(USNO) at a high level of precision to passive
users over a broad area of the South Pacific.

The concept is based on active two-way satellite time transfer from the United States Naval
Observatory (USNO) to the proposed USNO Master Clock West (MCW) in Wahiwa, HI USA at
the 1 nanosecond level using active satellite two-way time transfer augmented by Precise Positioning Service (PPS) of the Global Positioning System (GPS). MCW would act as an intermediate transfer/reference station, again linked to Salisbury at the 1 nanosecond level using active satellite two-way time transfer augmented by PPS GPS. From this point, time would bc distributed within the region by two methods. The first is an existing TV line sync system using an Australian communications satellite (AUSSAT K1) which is useful to the 20 nanosecond level. The second approach is RF ranging and multilateration between Salisbury, Orroral Observatory, Lower Hutt and the AUSSAT B1 and B2 to be launched in 1992. Orroral Observatory will provide precise laser ranging to the AUSSAT B1/B2 retro reflectors which will reduce ephemeris related time transfer errors to below 1 nanosecond. The corrected position will be transmitted by both the time transfer modem and the existing TV line sync dissemination process. Multilateration has the advantage of being an all weather approach and when used with the laser ranging technique will provide a precise measurement of the propagation path delays. This will result in time transfer performance levels on the order of 10 nanoseconds to passive users in both Australia and New Zealand.
Document ID
19920024138
Document Type
Conference Paper
Authors
John Luck
(Geoscience Australia Canberra, Australian Capital Territory, Australia)
John Dunkley
(Defence Science and Technology Group Canberra, Australian Capital Territory, Australia)
Tim Armstrong
(Crown Research Institutes Wellington, New Zealand)
Al Gifford
(Department of Defense Washington, DC., United States)
Paul Landis
(United States Department of Defense Washington D.C., District of Columbia, United States)
Scott Rasmussen
(United States Department of Defense Washington D.C., District of Columbia, United States)
Paul Wheeler
(United States Department of Defense Washington D.C., District of Columbia, United States)
Tom Bartholomew
(Analytic Sciences Corporation (TASC) Boulder, CO., United States)
Sam Stein
(Timing Solutions Corporation)
Date Acquired
September 6, 2013
Publication Date
December 3, 1991
Publication Information
Publication: 23rd Annual Time and Time Precise Interval (PTTI) Applications and Planning Meeting
Publisher: National Aeronautics and Space Administration
Volume: 3159
Issue Publication Date: January 1, 1992
Subject Category
Physics (General)
Meeting Information
Meeting: 23rd Annual Time and Time Precise Interval (PTTI) Applications and Planning Meeting
Location: Pasadena, CA
Country: US
Start Date: December 3, 1991
End Date: December 5, 1991
Sponsors: United States Naval Observatory, Goddard Space Flight Center, Jet Propulsion Lab
Accession Number
92N33382
Distribution Limits
Public
Copyright
Portions of document may include copyright protected material.
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