Time References in GNSS - Revision history

Natalia.Castrillo at 09:43, 23 March 2026

2026-03-23T09:43:54Z

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	==Galileo System Time (GST)==		==Galileo System Time (GST)==
	Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch, GST(T0), is defined 13 seconds before 0:00:00 UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).<ref name="Galileo OS ICD">[https://www.gsc-europa.eu/sites/default/files/sites/all/files/Galileo_OS_SIS_ICD_v2.2.pdf Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], EUSPA, Issue 2.2, November 2025</ref>		Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch, GST(T0), is defined 13 seconds before 0:00:00 UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).<ref name="Galileo OS ICD">[https://www.gsc-europa.eu/sites/default/files/sites/all/files/Galileo_OS_SIS_ICD_v2.2.pdf Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD), EUSPA, Issue 2.2, November 2025]</ref>

	==BeiDou Time (BDT)==		==BeiDou Time (BDT)==
	BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006<ref name="BDS B2b ICD">http://en.beidou.gov.cn/SYSTEMS/ICD/202008/P020231201537880833625.pdf BeiDou Navigation Satellite System Signal In Space Interface Control Document Open Service Signal B2b, China Satellite Navigation Office, Version 1.0, July 2020</ref>. In order to be as consistent as possible with UTC, BDT may steer to an interposed frequency adjustment after a period of time (more than 30 days) according to the situation, but the quantity of adjustment is not to allowed more than 5x10E-15 <ref>[https://nap.nationalacademies.org/read/13292/chapter/10#87 National Academies of Sciences, Engineering, and Medicine. 2012. Global Navigation Satellite Systems: Report of a Joint Workshop of the National Academy of Engineering and the Chinese Academy of Engineering. Washington, DC: The National Academies Press]</ref>.		BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006<ref name="BDS B2b ICD">[http://en.beidou.gov.cn/SYSTEMS/ICD/202008/P020231201537880833625.pdf BeiDou Navigation Satellite System Signal In Space Interface Control Document Open Service Signal B2b, China Satellite Navigation Office, Version 1.0, July 2020]</ref>. In order to be as consistent as possible with UTC, BDT may steer to an interposed frequency adjustment after a period of time (more than 30 days) according to the situation, but the quantity of adjustment is not to allowed more than 5x10E-15 <ref>[https://nap.nationalacademies.org/read/13292/chapter/10#87 National Academies of Sciences, Engineering, and Medicine. 2012. Global Navigation Satellite Systems: Report of a Joint Workshop of the National Academy of Engineering and the Chinese Academy of Engineering. Washington, DC: The National Academies Press]</ref>.

	==Notes==		==Notes==

Natalia.Castrillo at 09:41, 23 March 2026

2026-03-23T09:41:06Z

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	==GPS Time (GPST)==		==GPS Time (GPST)==
	GPS Time (GPST) is a continuous time scale (no leap seconds) defined by the GPS Control segment on the basis of a set of atomic clocks at the Monitor Stations and onboard the satellites. It starts at 0<sup>h</sup> UTC (midnight) of January 5th to 6th 1980 (6.<sup>d</sup>0). At that epoch, the difference TAI−UTC was 19 seconds, thence GPS−UTC=n − 19<sup>s</sup>. GPS time is synchronised with the UTC(USNO) at 1 microsecond level (modulo one second), but actually is kept within 25 ns.<ref>[~~http~~://~~www~~.gps.gov/technical/icwg/IS-GPS-~~200G~~.pdf GPS ~~Interface Specification~~, Navstar GPS Space Segment/Navigation User Segment Interfaces ~~(IS-GPS-200G)~~]~~, GPS Directorate, Revision G, 21 September 2011~~</ref>		GPS Time (GPST) is a continuous time scale (no leap seconds) defined by the GPS Control segment on the basis of a set of atomic clocks at the Monitor Stations and onboard the satellites. It starts at 0<sup>h</sup> UTC (midnight) of January 5th to 6th 1980 (6.<sup>d</sup>0). At that epoch, the difference TAI−UTC was 19 seconds, thence GPS−UTC=n − 19<sup>s</sup>. GPS time is synchronised with the UTC(USNO) at 1 microsecond level (modulo one second), but actually is kept within 25 ns.<ref name="GPS ICD 200">[https://archive.gps.gov/technical/icwg/IS-GPS-200N.pdf GPS ICD-200 Revision N, "Navstar GPS Space Segment/Navigation User Segment Interfaces"]</ref>

	==GLONASS Time (GLONASST)==		==GLONASS Time (GLONASST)==
	GLONASS Time (GLONASST) is generated by the GLONASS Central Synchroniser and the difference between the UTC(SU) and GLONASST should not exceed 1 millisecond plus three hours<ref group="footnotes">The difference between Moscow Time and Greenwich Mean Time (GMT).</ref> (i.e.,<math>GLONASST=UTC(SU)+3^h-\tau</math>, where <math>\|\tau\|< 1		GLONASS Time (GLONASST) is generated by the GLONASS Central Synchroniser and the difference between the UTC(SU) and GLONASST should not exceed 1 millisecond plus three hours<ref group="footnotes">The difference between Moscow Time and Greenwich Mean Time (GMT).</ref> (i.e.,<math>GLONASST=UTC(SU)+3^h-\tau</math>, where <math>\|\tau\|< 1
	milisec.</math>), but <math>\tau</math> is typically better than 1 microsecond. Note: Unlike GPS, Galileo or BeiDou, GLONASS time scale implements leap seconds, like UTC.<ref>~~[http://www.spacecorp.ru/upload/iblock/1c4/cgs-aaixymyt%205.1%20ENG%20v%202014.02.18w.pdf~~ GLONASS Interface Control Document~~, Navigation radiosignal In bands L1, L2 (ICD L1, L2 GLONASS)]~~, Russian Institute of Space Device Engineering, Edition 5.1, 2008</ref>		milisec.</math>), but <math>\tau</math> is typically better than 1 microsecond. Note: Unlike GPS, Galileo or BeiDou, GLONASS time scale implements leap seconds, like UTC.<ref name="GLONASS ICD">GLONASS Interface Control Document, Russian Institute of Space Device Engineering, Edition 5.1, 2008</ref>

	==Galileo System Time (GST)==		==Galileo System Time (GST)==
	Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch, GST(T0), is defined 13 seconds before 0:00:00 UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).<ref>[~~http~~://ec.europa.eu/~~DocsRoom~~/~~documents~~/~~11870~~/~~attachments~~/1/~~translations~~/~~en/renditions/native~~ Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], ~~GSA~~, Issue 1.1, ~~September 2010~~</ref>		Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch, GST(T0), is defined 13 seconds before 0:00:00 UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).<ref name="Galileo OS ICD">[https://www.gsc-europa.eu/sites/default/files/sites/all/files/Galileo_OS_SIS_ICD_v2.2.pdf Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], EUSPA, Issue 2.2, November 2025</ref>

	==BeiDou Time (BDT)==		==BeiDou Time (BDT)==
	BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006<ref> BeiDou Signal In Space Interface Control Document, Open Service Signal ~~(BDS-SIS-ICD-2.0)~~, China Satellite Navigation Office, Version 2.0, ~~December 2013~~</ref>. In order to be as consistent as possible with UTC, BDT may steer to an interposed frequency adjustment after a period of time (more than 30 days) according to the situation, but the quantity of adjustment is not to allowed more than 5x10E-15 <ref>[https://nap.nationalacademies.org/read/13292/chapter/10#87 National Academies of Sciences, Engineering, and Medicine. 2012. Global Navigation Satellite Systems: Report of a Joint Workshop of the National Academy of Engineering and the Chinese Academy of Engineering. Washington, DC: The National Academies Press]</ref>.		BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006<ref name="BDS B2b ICD">http://en.beidou.gov.cn/SYSTEMS/ICD/202008/P020231201537880833625.pdf BeiDou Navigation Satellite System Signal In Space Interface Control Document Open Service Signal B2b, China Satellite Navigation Office, Version 1.0, July 2020</ref>. In order to be as consistent as possible with UTC, BDT may steer to an interposed frequency adjustment after a period of time (more than 30 days) according to the situation, but the quantity of adjustment is not to allowed more than 5x10E-15 <ref>[https://nap.nationalacademies.org/read/13292/chapter/10#87 National Academies of Sciences, Engineering, and Medicine. 2012. Global Navigation Satellite Systems: Report of a Joint Workshop of the National Academy of Engineering and the Chinese Academy of Engineering. Washington, DC: The National Academies Press]</ref>.

	==Notes==		==Notes==

Gema.Cueto at 06:41, 11 September 2023

2023-09-11T06:41:31Z

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	==BeiDou Time (BDT)==		==BeiDou Time (BDT)==
	BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006<ref> BeiDou Signal In Space Interface Control Document, Open Service Signal (BDS-SIS-ICD-2.0), China Satellite Navigation Office, Version 2.0, December 2013</ref>. In order to be as consistent as possible with UTC, BDT may steer to an interposed frequency adjustment after a period of time (more than 30 days) according to the situation, but the quantity of adjustment is not to allowed more than 5x10E-15 <ref>[National Academies of Sciences, Engineering, and Medicine. 2012. Global Navigation Satellite Systems: Report of a Joint Workshop of the National Academy of Engineering and the Chinese Academy of Engineering. Washington, DC: The National Academies Press ~~https://nap.nationalacademies.org~~/~~read/13292/chapter/10#87]~~.		BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006<ref> BeiDou Signal In Space Interface Control Document, Open Service Signal (BDS-SIS-ICD-2.0), China Satellite Navigation Office, Version 2.0, December 2013</ref>. In order to be as consistent as possible with UTC, BDT may steer to an interposed frequency adjustment after a period of time (more than 30 days) according to the situation, but the quantity of adjustment is not to allowed more than 5x10E-15 <ref>[https://nap.nationalacademies.org/read/13292/chapter/10#87 National Academies of Sciences, Engineering, and Medicine. 2012. Global Navigation Satellite Systems: Report of a Joint Workshop of the National Academy of Engineering and the Chinese Academy of Engineering. Washington, DC: The National Academies Press]</ref>.

	==Notes==		==Notes==

Gema.Cueto: /* BeiDou Time (BDT) */

2023-09-11T06:40:11Z

BeiDou Time (BDT)

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	==BeiDou Time (BDT)==		==BeiDou Time (BDT)==
	BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006 ~~and is synchronised with UTC within 100 ns< (modulo one second).~~<ref> BeiDou Signal In Space Interface Control Document, Open Service Signal (BDS-SIS-ICD-2.0), China Satellite Navigation Office, Version 2.0, December 2013</ref>		BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006<ref> BeiDou Signal In Space Interface Control Document, Open Service Signal (BDS-SIS-ICD-2.0), China Satellite Navigation Office, Version 2.0, December 2013</ref>. In order to be as consistent as possible with UTC, BDT may steer to an interposed frequency adjustment after a period of time (more than 30 days) according to the situation, but the quantity of adjustment is not to allowed more than 5x10E-15 <ref>[National Academies of Sciences, Engineering, and Medicine. 2012. Global Navigation Satellite Systems: Report of a Joint Workshop of the National Academy of Engineering and the Chinese Academy of Engineering. Washington, DC: The National Academies Press https://nap.nationalacademies.org/read/13292/chapter/10#87].

	==Notes==		==Notes==

Gema.Cueto: /* Galileo System Time (GST) */

2020-11-04T13:38:01Z

Galileo System Time (GST)

← Older revision		Revision as of 13:38, 4 November 2020
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	==Galileo System Time (GST)==		==Galileo System Time (GST)==
	Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch, GST(T0), is defined 13 seconds before 0:00:00 UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August)..<ref>[http://ec.europa.eu/DocsRoom/documents/11870/attachments/1/translations/en/renditions/native Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], GSA, Issue 1.1, September 2010</ref>		Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch, GST(T0), is defined 13 seconds before 0:00:00 UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).<ref>[http://ec.europa.eu/DocsRoom/documents/11870/attachments/1/translations/en/renditions/native Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], GSA, Issue 1.1, September 2010</ref>

	==BeiDou Time (BDT)==		==BeiDou Time (BDT)==

Gema.Cueto: /* Galileo System Time (GST) */

2020-11-04T13:37:45Z

Galileo System Time (GST)

← Older revision		Revision as of 13:37, 4 November 2020
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	==Galileo System Time (GST)==		==Galileo System Time (GST)==
	Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch is 0~~<sup>h</sup>~~ UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).<ref>[http://ec.europa.eu/DocsRoom/documents/11870/attachments/1/translations/en/renditions/native Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], GSA, Issue 1.1, September 2010</ref>		Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch, GST(T0), is defined 13 seconds before 0:00:00 UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August)..<ref>[http://ec.europa.eu/DocsRoom/documents/11870/attachments/1/translations/en/renditions/native Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], GSA, Issue 1.1, September 2010</ref>

	==BeiDou Time (BDT)==		==BeiDou Time (BDT)==

Claudia.Prajanu at 11:50, 27 July 2018

2018-07-27T11:50:22Z

← Older revision		Revision as of 11:50, 27 July 2018
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	==Galileo System Time (GST)==		==Galileo System Time (GST)==
	Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch is 0<sup>h</sup> UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).<ref>[http://ec.europa.eu/~~enterprise~~/~~policies~~/~~satnav~~/~~galileo~~/~~files~~/~~galileo-os-sis-icd-issue1-revision1_en.pdf~~ Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], GSA, Issue 1.1, September 2010</ref>		Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch is 0<sup>h</sup> UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).<ref>[http://ec.europa.eu/DocsRoom/documents/11870/attachments/1/translations/en/renditions/native Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], GSA, Issue 1.1, September 2010</ref>

	==BeiDou Time (BDT)==		==BeiDou Time (BDT)==
	BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006 and is synchronised with UTC within 100 ns< (modulo one second).<ref>~~[http://interact.beidou.gov.cn/interact/download.service?attachment=2013/12/26/20131226b8a6182fa73a4ab3a5f107f762283712.pdf~~ BeiDou Signal In Space Interface Control Document, Open Service Signal (BDS-SIS-ICD-2.0)], China Satellite Navigation Office, Version 2.0, December 2013</ref>		BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006 and is synchronised with UTC within 100 ns< (modulo one second).<ref> BeiDou Signal In Space Interface Control Document, Open Service Signal (BDS-SIS-ICD-2.0), China Satellite Navigation Office, Version 2.0, December 2013</ref>

	==Notes==		==Notes==

Filipe.Pelica: /* GLONASS Time (GLONASST) */

2014-05-26T17:39:47Z

GLONASS Time (GLONASST)

← Older revision		Revision as of 17:39, 26 May 2014
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	==GLONASS Time (GLONASST)==		==GLONASS Time (GLONASST)==
	GLONASS Time (GLONASST) is generated by the GLONASS Central Synchroniser and the difference between the UTC(SU) and GLONASST should not exceed 1 millisecond plus three hours<ref group="footnotes">The difference between Moscow Time and Greenwich Mean Time (GMT).</ref> (i.e.,<math>GLONASST=UTC(SU)+3^h-\tau</math>, where <math>\|\tau\|< 1		GLONASS Time (GLONASST) is generated by the GLONASS Central Synchroniser and the difference between the UTC(SU) and GLONASST should not exceed 1 millisecond plus three hours<ref group="footnotes">The difference between Moscow Time and Greenwich Mean Time (GMT).</ref> (i.e.,<math>GLONASST=UTC(SU)+3^h-\tau</math>, where <math>\|\tau\|< 1
	milisec.</math>), but <math>\tau</math> is typically better than 1 microsecond. Note: Unlike GPS, Galileo or ~~Compass~~, GLONASS time scale implements leap seconds, like UTC.<ref>[http://www.spacecorp.ru/upload/iblock/1c4/cgs-aaixymyt%205.1%20ENG%20v%202014.02.18w.pdf GLONASS Interface Control Document, Navigation radiosignal In bands L1, L2 (ICD L1, L2 GLONASS)], Russian Institute of Space Device Engineering, Edition 5.1, 2008</ref>		milisec.</math>), but <math>\tau</math> is typically better than 1 microsecond. Note: Unlike GPS, Galileo or BeiDou, GLONASS time scale implements leap seconds, like UTC.<ref>[http://www.spacecorp.ru/upload/iblock/1c4/cgs-aaixymyt%205.1%20ENG%20v%202014.02.18w.pdf GLONASS Interface Control Document, Navigation radiosignal In bands L1, L2 (ICD L1, L2 GLONASS)], Russian Institute of Space Device Engineering, Edition 5.1, 2008</ref>

	==Galileo System Time (GST)==		==Galileo System Time (GST)==

Filipe.Pelica: rewritten first paragraph.

2014-05-19T12:42:03Z

rewritten first paragraph.

← Older revision		Revision as of 12:42, 19 May 2014
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	\|Title={{PAGENAME}}		\|Title={{PAGENAME}}
	}}		}}
	~~Regarding the GNSS, the GPS Time (GPST), GLONASS Time (GLONASST), Galileo System Time (GST) and BeiDou Time (BDT) are the reference times used in GPS, GLONASS and Galileo applications, respectively.~~

			GNSS Systems strongly rely on measuring the time of arrival of radio signals propagation. Thus, each GNSS System has its own time reference from which all elements of the Space, Control and User segments are time synchronized, as well most of the [[GNSS Applications\|GNSS-based applications]].
			The most relevant GNSS time references are briefly described below.

	GPS Time (GPST) is a continuous time scale (no leap seconds) defined by the GPS Control segment on the basis of a set of atomic clocks at the Monitor Stations and onboard the satellites. It starts at 0<sup>h</sup> UTC (midnight) of January 5th to 6th 1980 (6.<sup>d</sup>0). At that epoch, the difference TAI−UTC was 19 seconds, thence GPS−UTC=n − 19<sup>s</sup>. GPS time is synchronised with the UTC(USNO) at 1 microsecond level (modulo one second), but actually is kept within 25 ns.		==GPS Time (GPST)==
			GPS Time (GPST) is a continuous time scale (no leap seconds) defined by the GPS Control segment on the basis of a set of atomic clocks at the Monitor Stations and onboard the satellites. It starts at 0<sup>h</sup> UTC (midnight) of January 5th to 6th 1980 (6.<sup>d</sup>0). At that epoch, the difference TAI−UTC was 19 seconds, thence GPS−UTC=n − 19<sup>s</sup>. GPS time is synchronised with the UTC(USNO) at 1 microsecond level (modulo one second), but actually is kept within 25 ns.<ref>[http://www.gps.gov/technical/icwg/IS-GPS-200G.pdf GPS Interface Specification, Navstar GPS Space Segment/Navigation User Segment Interfaces (IS-GPS-200G)], GPS Directorate, Revision G, 21 September 2011</ref>

			==GLONASS Time (GLONASST)==
	GLONASS Time (GLONASST) is generated by the GLONASS Central Synchroniser and the difference between the UTC(SU) and GLONASST should not exceed 1 millisecond plus three hours<ref group="footnotes">The difference between Moscow Time and Greenwich Mean Time (GMT).</ref> (i.e.,<math>GLONASST=UTC(SU)+3^h-\tau</math>, where <math>\|\tau\|< 1		GLONASS Time (GLONASST) is generated by the GLONASS Central Synchroniser and the difference between the UTC(SU) and GLONASST should not exceed 1 millisecond plus three hours<ref group="footnotes">The difference between Moscow Time and Greenwich Mean Time (GMT).</ref> (i.e.,<math>GLONASST=UTC(SU)+3^h-\tau</math>, where <math>\|\tau\|< 1
	milisec.</math>), but <math>\tau</math> is typically better than 1 microsecond. Note: Unlike GPS, Galileo or Compass, GLONASS time scale implements leap seconds, like UTC.		milisec.</math>), but <math>\tau</math> is typically better than 1 microsecond. Note: Unlike GPS, Galileo or Compass, GLONASS time scale implements leap seconds, like UTC.<ref>[http://www.spacecorp.ru/upload/iblock/1c4/cgs-aaixymyt%205.1%20ENG%20v%202014.02.18w.pdf GLONASS Interface Control Document, Navigation radiosignal In bands L1, L2 (ICD L1, L2 GLONASS)], Russian Institute of Space Device Engineering, Edition 5.1, 2008</ref>

			==Galileo System Time (GST)==
			Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch is 0<sup>h</sup> UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).<ref>[http://ec.europa.eu/enterprise/policies/satnav/galileo/files/galileo-os-sis-icd-issue1-revision1_en.pdf Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD)], GSA, Issue 1.1, September 2010</ref>

	~~Galileo System~~ Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. The GST start epoch is 0<sup>h</sup> UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).		==BeiDou Time (BDT)==
			BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006 and is synchronised with UTC within 100 ns< (modulo one second).<ref>[http://interact.beidou.gov.cn/interact/download.service?attachment=2013/12/26/20131226b8a6182fa73a4ab3a5f107f762283712.pdf BeiDou Signal In Space Interface Control Document, Open Service Signal (BDS-SIS-ICD-2.0)], China Satellite Navigation Office, Version 2.0, December 2013</ref>

	BeiDou Time (BDT) is a continuous time scale starting at 0<sup>h</sup> UTC on January 1st, 2006 and is synchronised with UTC within 100 ns< (modulo one second), [BeiDou-SIS-ICD-~~Test~~, ~~2011]~~.


	==Notes==		==Notes==
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	==References==		==References==
	* BeiDou-SIS-ICD-Test, 2011. Technical report. BeiDou Navigation Satellite System Signal In Space. Interface Control Document (Test version), December 2011.		<references/>


	[[Category:Fundamentals]]		[[Category:Fundamentals]]
	[[Category:GNSS Time Reference, Coordinate Frames and Orbits]]		[[Category:GNSS Time Reference, Coordinate Frames and Orbits]]

Filipe.Pelica: footnotes harmonizing

2014-01-10T16:29:34Z

footnotes harmonizing

← Older revision		Revision as of 16:29, 10 January 2014
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	GLONASS Time (GLONASST) is generated by the GLONASS Central Synchroniser and the difference between the UTC(SU) and GLONASST should not exceed 1 millisecond plus three hours<ref group="~~footnote~~">The difference between Moscow Time and Greenwich Mean Time (GMT).</ref> (i.e.,<math>GLONASST=UTC(SU)+3^h-\tau</math>, where <math>\|\tau\|< 1		GLONASS Time (GLONASST) is generated by the GLONASS Central Synchroniser and the difference between the UTC(SU) and GLONASST should not exceed 1 millisecond plus three hours<ref group="footnotes">The difference between Moscow Time and Greenwich Mean Time (GMT).</ref> (i.e.,<math>GLONASST=UTC(SU)+3^h-\tau</math>, where <math>\|\tau\|< 1
	milisec.</math>), but <math>\tau</math> is typically better than 1 microsecond. Note: Unlike GPS, Galileo or Compass, GLONASS time scale implements leap seconds, like UTC.		milisec.</math>), but <math>\tau</math> is typically better than 1 microsecond. Note: Unlike GPS, Galileo or Compass, GLONASS time scale implements leap seconds, like UTC.

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	==Notes==		==Notes==
	<references group="~~footnote~~"/>		<references group="footnotes"/>

	==References==		==References==