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The National Technical Information Service acquires, indexes, abstracts, and archives the largest collection of U.S. government-sponsored technical reports in existence. The NTRL offers online, free and open access to these authenticated government technical reports. Technical reports and documents in its repository may be available online for free either from the issuing federal agency, the U.S. Government Publishing Office’s Federal Digital System website, or through search engines.

Details

Off-Air Observatory Time Service.

ADA519496

Publication Date	1987
Personal Author	Seabrook, A. R.
Page Count	21
Abstract	When the decision was taken to severely reduce the funding for the Greenwich Time Service, an alternative precision time service had to be found, so that the Satellite Laser Ranger could continue to operate. There were certain constraints on the alternative such as, high precision, highly reliable, not labour intensive, physically small and inexpensive. This paper shows how this was achieved. It is considered to be a unique solution not achieved before and provides an elegant solution to an inherently complex problem. Great reliance is put upon external agencies to provide the infrastructure to maintain their equipment. Use is made of the LORAN-C chain of stations for the frequency references and the Global Positioning System satellite for the Time of Day and traceability. This is a one rack complete observatory time service and the results compare very favourably with the remaining standards on site.
Keywords	Artificial satellites Time United kingdom Global positioning system Precision Satellite constellations Cost effectiveness Observatories Infrastructure Lasers Range finding Off-air observatory time service Precision time Foreign reports Satellite laser ranger Loran-c stations Ca stds(Caesium standards)
Source Agency	Non Paid ADAS
Corporate Authors	Royal Greenwich Observatory, Herstmonceux (England).
Supplemental Notes	Presented at the Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting (19th) held in Redondo Beach, CA on 1- 3 December 1987. Published in the Proceedings of the Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting (19th), p49-68, December 1987.
Document Type	Technical Report
Title Note	Conference paper.
NTIS Issue Number	201018

Off-Air Observatory Time Service.

Off-Air Observatory Time Service.
ADA519496

Publication Date	1987
Personal Author	Seabrook, A. R.
Page Count	21
Abstract	When the decision was taken to severely reduce the funding for the Greenwich Time Service, an alternative precision time service had to be found, so that the Satellite Laser Ranger could continue to operate. There were certain constraints on the alternative such as, high precision, highly reliable, not labour intensive, physically small and inexpensive. This paper shows how this was achieved. It is considered to be a unique solution not achieved before and provides an elegant solution to an inherently complex problem. Great reliance is put upon external agencies to provide the infrastructure to maintain their equipment. Use is made of the LORAN-C chain of stations for the frequency references and the Global Positioning System satellite for the Time of Day and traceability. This is a one rack complete observatory time service and the results compare very favourably with the remaining standards on site.
Keywords	Artificial satellites Time United kingdom Global positioning system Precision Satellite constellations Cost effectiveness Observatories Infrastructure Lasers Range finding Off-air observatory time service Precision time Foreign reports Satellite laser ranger Loran-c stations Ca stds(Caesium standards)
Source Agency	Non Paid ADAS
Corporate Authors	Royal Greenwich Observatory, Herstmonceux (England).
Supplemental Notes	Presented at the Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting (19th) held in Redondo Beach, CA on 1- 3 December 1987. Published in the Proceedings of the Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting (19th), p49-68, December 1987.
Document Type	Technical Report
Title Note	Conference paper.
NTIS Issue Number	201018