Experimental assessment of the time transfer capability of precise point positioning (PPP)

Orgiazzi, D.; Tavella, P.; Lahaye, F.

doi:10.1109/freq.2005.1573955

Cited by 44 publications

(35 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The coefficient ε ≥ 0 quantifies the fidelity F, and ε 0 ≥ 0 quantifies the fidelity F 0 . The coefficients can be considered as defining the response of a filter with transfer functions T( f ) and T 0 ( f ), respectively, where T( f ) = 1/(1 + (1/ε)(2π f ) 6 ) and T 0 ( f ) = 1/(1 + (1/ε 0 )(2π f ) 4 ). The dimensions of ε and ε 0 are time −6 and time −4 , respectively.…”

Section: Combination Of Ppp With Two-way Time Transfermentioning

confidence: 99%

“…This is possible thanks to the precise satellite orbits and clocks provided by the International GNSS Service (IGS) [2], where the reference time scale is IGS time [3]. In recent years, the time community has shown a growing interest in this technique and a number of time transfer experiments have been carried out (see, e.g., [4][5][6]). …”

Section: Introductionmentioning

confidence: 99%

“…Receivers able to measure phase and code are becoming commonplace in time laboratories. For this reason, the CCTF, at its 17th meeting in September 2006 [1] passed a recommendation "Concerning the use of Global Navigation Satellite System (GNSS) carrier phase techniques for time and frequency transfer in International Atomic Time (TAI)," in which it asked that "the International Bureau of Weights and Measures (BIPM), in a highly cooperative manner, generate its own solutions, make them freely available to others, and add them to its time transfer comparison database," and that "the BIPM begin preparing software and techniques for introduction of the data into the computation of Circular T" (excerpts from Recommendation CCTF 4,2006).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Precise Point Positioning for TAI Computation

Petit

Jiang

2008

International Journal of Navigation and Observation

View full text Add to dashboard Cite

We discuss the use of some new time transfer techniques for computing TAI time links. Precise point positioning (PPP) uses GPS dual frequency carrier phase and code measurements to compute the link between a local clock and a reference time scale with the precision of the carrier phase and the accuracy of the code. The time link between any two stations can then be computed by a simple difference. We show that this technique is well adapted and has better short-term stability than other techniques used in TAI. We present a method of combining PPP and two-way time transfer that takes advantage of the qualities of each technique, and shows that it would bring significant improvement to TAI links.

show abstract

Section: Combination Of Ppp With Two-way Time Transfermentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Precise Point Positioning for TAI Computation

Petit

Jiang

2008

International Journal of Navigation and Observation

View full text Add to dashboard Cite

show abstract

“…Measurements were performed over a two month period with data collected relative to the maser frequency. The maser is calibrated in its absolute offset from the SI second through international GPS satellite intercomparison using the Natural Resources Canada Precise Point Positioning (PPP) data-processing technique [27] and using the Bureau International des Poids et Mesures (BIPM) circular-T reports. Using such corrections together with NRC inhouse frequency standards, it was possible to obtain uncertainties of the measured ion center frequency to a resulting final value of 0.9 Hz.…”

Section: H Y S I C a L R E V I E W L E T T E R Smentioning

confidence: 99%

Optical Atomic Clocks Could Redefine Unit of Time

Riehle¹

2012

Physics

View full text Add to dashboard Cite

We describe experiments and measurements on a trapped and laser-cooled single ion of 88 Sr þ which, when probed on its reference 5s 2 S 1=2 ! 4d 2 D 5=2 transition at 445 THz, provides an optical frequency standard of evaluated accuracy outperforming the current realization of the SI second. Studies are presented showing that micromotion-associated shifts of the standard can be reduced to the 10 À18 level and uncertainties in the blackbody-induced shifts for the current system are at the low 10 À17 level due to the relatively well-known polarizability of the strontium ion system and careful choice of the trap structure. The current evaluated systematic shifts for the ion transition are at a fractional uncertainty of 2 Â 10 À17 . An absolute frequency measurement performed over a two-month period relative to a maser referenced to the SI second via Global Positioning System time transfer has determined the center frequency for the transition at SD ¼ 444 779 044 095 485:5 AE 0:9 Hz (1 ). DOI: 10.1103/PhysRevLett.109.203002 PACS numbers: 06.30.Ft, 32.70.Jz, 37.10.Ty, 42.50.Lc From precision tests of relativity to the increased understanding of atomic physics and fundamental constants, atomic time standards have helped shed light on subtle physical phenomena that underlie fundamental concepts of physics [1][2][3]. In addition, these references underpin the SI system which forms the basis of physical measurement. New experimental systems employing dipole forbidden optical transitions in trapped and laser-cooled ions and neutral atoms have been shown to be excellent nextgeneration realizations of ultra-accurate frequency references [3][4][5][6][7][8][9][10][11][12][13][14]. Such systems now have evaluated accuracies that exceed the current realizations of the definition of the SI second as realized by a microwave transition in Cs atoms [15]. Among the trapped ion systems studied, the 88 Sr þ 5s 2 S 1=2 ! 4d 2 D 5=2 electric dipole forbidden transition at 445 THz (674 nm) has a very high quality factor (Q ¼ 0 =Á ¼ 10 15 ) and possesses a relatively simple electronic energy level scheme that is favorable for use with widely available solid state laser technology [16]. This ion system was the first to be directly measured against the Cs realization of the second [17] and has been established as one of the secondary representations of the SI second. This system has been primarily studied at the Frequency and Time Group, National Research Council of Canada (NRC) and the National Physical Laboratory (NPL) in the United Kingdom [7,11] with additional groups recently providing results [18]. We describe new results and methods by which the systematic shifts for the system have been reduced to the low 10 À17 level via operation of the trap system under conditions which reduce and in some cases null out significant uncertainties which dominate many optical reference systems. The work also provides a new measurement of the transition center frequency relative to the SI second.A single atomic ion of 88 Sr þ is held in an electr...

show abstract

“…from multi-path or temperature dependences) may has a larger effect on clock jumps between arcs. Various methods for mitigating or compensating daily jumps such as phase-only method, sliding batch solution (SBS), clock handover and so on are already presented in (Orgiazzi et al 2005, Dach et al 2006, Defraigne et al 2008. However, fully compensation method is not yet presented.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of Daily Jump Compensation Methods for GPS Carrier Phase Data

Lee¹,

Yang²,

Lee³

et al. 2015

Journal of Positioning, Navigation, and Timing

View full text Add to dashboard Cite

In this paper, we described the timing-offset comparison results between various daily jump compensation methods for GPS carrier phase (CP) measurement data. For the performance comparison, we used about 70 days GPS measurement data obtained from two GPS geodetic receivers which share the reference 1 PPS and RF signals and closely located in each other within a few meters. From the experiment results, the followings were observed. First, daily jumps existed in CP measurements depend on not only the environment but also the receiver which will make a full compensation be very hard or impossible. Second, clock bias can be occurred in the case of using a simple compensation with accumulation of daily jumps but it could be used in a short-period frequency comparison campaign (less than about 7 days) despite of its drawback.

show abstract

Experimental assessment of the time transfer capability of precise point positioning (PPP)

Cited by 44 publications

References 9 publications

Precise Point Positioning for TAI Computation

Precise Point Positioning for TAI Computation

Optical Atomic Clocks Could Redefine Unit of Time

Evaluation of Daily Jump Compensation Methods for GPS Carrier Phase Data

Contact Info

Product

Resources

About