STATE SCIENTIFIC CENTER OF THE RUSSIAN

FEDERATION

NATIONAL RESEARCH INSTITUTE FORPHYSICAL-TECHNICAL AND RADIO ENGINEERING MEASUREMENTS

GENERATION OF THE NATIONAL TIME SCALE UTC(SU), ITS TRANSFER TO GLONASS AND

HARMONIZATION WITH UTC

ICG-7WG-D

Igor Silvestrov4-9 november 2012, ICG-7, Beijing

Federal Law "On the calculation of time» № 107-FZ of 04.03.2011National scale of the Russian Federation - an ordered sequence of numbers of units of time, reproduced and stored by the State Service of Time, Frequency and Earth's Orientation Parameters on the basis of the State primary standard of time, frequency, and the national time scale.

Government Decree № 323 of 30.04.2008Federal Agency for Technical Regulation and Metrology carries out the support for GLONASS reference values of time and frequency, the national time scale and the Earth's Orientation Parameters data.

Interface control document GLONASS ICD 05.01, March 2008Reference time scale for the GLONASS system is the national time scale UTC(SU).

Main documents, that set the legal basis for generation and transferring of the national time scale UTC(SU) to GLONASS

Generation of the National time scale UTC(SU)

CSFO1 VNIIFTRICSFO1 VNIIFTRIaccuracy accuracy ≤≤ 5.0 E5.0 E--1616

8 8 HH--Maser clocksMaser clocksKvarzKvarz CHCH11--7575AAσσyy((ττ) ) ≤≤ 5 E5 E--16 per 16 per dayday

Physical Physical UTC(SU) UTC(SU) realizationrealizationaccuracy accuracy ≤≤ 0.5 ns0.5 ns

Physical Physical UTC(SU) RealizationUTC(SU) Realization

Switch

Primary SetPrimary Set

Backup SetBackup Set

PC

5MHz5MHz

1PPS1PPS

PR UTC(SU)AutomaticAutomatic switchingswitching inin casecase

ofof emergencyemergency situationssituations

UTC(SU) UTC(SU) –– PR UTC(SU) PR UTC(SU) ≤≤ 0.5 ns0.5 ns

HH--Maser 1Maser 1

HH--Maser 2Maser 2

Time Scale Sub Time Scale Sub System 1System 1

Time Scale Sub Time Scale Sub System 2System 2

5MHz5MHz

5MHz5MHz

1PPS1PPS

1PPS1PPS

5MHz5MHz

1PPS1PPS

AutomaticAutomatic controlcontrol

AutomaticAutomatic controlcontrol

UTC(SU) UTC(SU) –– HM(iHM(i))

Time Transfer System Time Transfer System from VNIIFTRI to GLONASS from VNIIFTRI to GLONASS GroundGround ControlControl SegmentSegment

TTSTTS--44receivers

GPS/GLONASS C/A and P3

GroundGround ControlControlSegmentSegment Equipment

VNIIFTRI VNIIFTRI Equipment

Uncertainty:

Uа ≈ 1 nsUв ≈ 2 ns

PTBPTBBIPM PTBUTC(SU)

GNSS

UTC(k)

UTC

TWSTFT

Harmonization of UTC(SU) and UTCHarmonization of UTC(SU) and UTC

Eu‐Asia link:PTB

NICTNIM

NMIJNTSC

KRISSTL

NPLI

Results of the UTC(USNO) и UTC(SU) matching using the GPS receivers

Uncertainty:- Uа ≈ 5,0 ns- Uв ≈ 5 ÷ 7 ns (with calibration)

SU01 TWSTFT Stationary station

•• Satellite: AM2 (80Satellite: AM2 (80°°E)E)•• Antenna: 1.8 metersAntenna: 1.8 meters•• TimeTechTimeTech SATRE 2 channel modemSATRE 2 channel modem•• Up and Down converter : Up and Down converter : ComtechComtech Company, 8 WCompany, 8 W•• TimeTechTimeTech SATSIMSATSIM•• Links with PTB and AsiaLinks with PTB and Asia

TWSTFT linkUTC(SU) - UTC(PTB)

Uncertainty:Uа ≈ 0.5 nsUв ≈ 2.0 ns(after calibration)

TWSTFT link UTC(SU) - UTC(PTB)

UTC(SU) - UTC(PTB)

-5

-4

-3

-2

-1

0

1

2

3

4

5

15.08.12 16.08.12 17.08.12 18.08.12 19.08.12 20.08.12 21.08.12 22.08.12 23.08.12

ns

Uncertainty:- Uа ≈ 0.3 ns- Uв ≈ 1 ÷ 2 ns

PTB - time scale matching center using TWSTFT

Links to European Sites:AOS PTF1+2INRIM ROAIPQ SPNPL TIMOCA TUGOP VSL

Links to US Institutes:NISTUSNO

Links to East-Europe and Asia:

NICTNIM

NMIJNTSC

KRISSTL

VNIIFTRINPLI

SU02 TWSTFT Transportable StationSU02 TWSTFT Transportable Station•• Satellite: AM2 (80Satellite: AM2 (80°°E)E)• Antenna: 1.2 metersAntenna: 1.2 meters•• TimeTechTimeTech SATRE 1 channel modemSATRE 1 channel modem•• Up and Down converter : Cross Tech, 16 WUp and Down converter : Cross Tech, 16 W•• TimeTechTimeTech SATSIMSATSIM•• Transportable HTransportable H--Maser clock Maser clock KvarzKvarz CH1CH1--76A, 76A, σσyy((ττ) ) ≤≤ 5E5E--1515

Calibration Uncertainty:Uа ≈ 0.5 nsUв ≈ 1.0 ns

VNIIFTRI SU01 VNIIFTRI SU01 –– SU02 Short base line experiment dataSU02 Short base line experiment data

Uncertainty:Uа ≈ 0.2 nsUв ≈ 0.5 ns

SU01 - SU02

-2,0

-1,5

-1,0

-0,5

0,0

0,5

1,0

1,5

2,0

56146 56147 56148 56149 5615028.07.2012 - 31.07.2012

ns

Potential coverage area for the new Luch-5B satellite Ku-range

Potential characteristics of the UTC(SU) and UTC(USNO) matching:

- continuous real-time mode- Uncertainty Uа ≈ 0,1 ÷ 0,3 ns- Uncertainty Uв ≈ 1 ÷ 2 ns

USNO

SU

Characteristics for the possible methods of UTC(SU) иUTC(USNO) matching

1. The same existing GNSS receivers set both in VNIIFTRI and USNOUncertainty Uа ≈ 5 nsUncertainty Uв ≈ 5 ÷ 7 ns delay - 1 day

2. Existing TWSTFT scheme: VNIIFTRI – РТВ – USNOUncertainty Uа ≈ 1 nsUncertainty Uв ≈ 3 ÷ 4 ns delay - 1 day

3. Perspective TWSTFT scheme using «Luch–5B»: VNIIFTRI – USNOUncertainty Uа ≈ 0,3 nsUncertainty Uв ≈ 1 ÷ 2 ns

continuous real-time mode

Proposals on the UTC(SU) and UTC harmonization accuracy increase

1. Set the GNSS time receivers (GLONASS/GPS) of the same type in VNIIFTRI and USNO as well as on the GPS Master Control Station and in the GLONASS Ground control segment

2. Organize the direct UTC(SU) and UTC(USNO) time scales matching using new satellite “Luch-5B”

Thank you for your attention!