Details
| Original language | English |
|---|---|
| Pages (from-to) | 229-238 |
| Number of pages | 10 |
| Journal | Advances in space research |
| Volume | 47 |
| Issue number | 2 |
| Publication status | Published - 25 Jun 2010 |
Abstract
Processing data from Global Navigation Satellite Systems (GNSS) always requires time synchronization between transmitter and receiver clocks. Due to the limited stability of the receiver's internal oscillator, the offset of the receiver clock with respect to the system time has to be estimated for every observation epoch or eliminated by processing differences between simultaneous observations. If, in contrast, the internal oscillator of the receiver is replaced by a stable atomic clock one can try to model the receiver clock offset, instead of estimating it on an epoch-by-epoch basis. In view of the progress made in the field of high-precision frequency standards we will investigate the technical requirements for GNSS receiver clock modeling at the carrier phase level and analyze its impact on the precision of the position estimates. If we want to take advantage of the frequency stability provided by a high-performance oscillator in combination with a GNSS receiver we have to ensure that the signal delays inside the receiver hardware remain constant. Therefore, we have analyzed the relative receiver clock offsets for a number of GNSS receivers that derive their frequency reference from a common oscillator. Based on experimental data of an exemplary pair of geodetic receivers we show that the noise from variations of the hardware delays in the receiver electronics does not exceed the receiver clock noise (5 ps RMS) when all environmental effects are carefully controlled. By analyzing the elements of the parameter covariance matrix for a simple case of point positioning, the impact of GNSS receiver clock modeling on kinematic and static solutions is studied. Furthermore, we demonstrate the suitability of a single quadratic polynomial to model a receiver clock that is locked to the frequency of an active hydrogen maser for periods up to 24 h. Based on simulated and real GNSS data it is shown that receiver clock modeling improves the RMS of the height component of a kinematic Precise Point Positioning (PPP) by up to 70%, whereas for the static case the gain is almost negligible.
Keywords
- Atomic clocks, Clock modeling, GNSS, Hardware delays, PPP
ASJC Scopus subject areas
- Engineering(all)
- Aerospace Engineering
- Physics and Astronomy(all)
- Astronomy and Astrophysics
- Earth and Planetary Sciences(all)
- Geophysics
- Earth and Planetary Sciences(all)
- Atmospheric Science
- Earth and Planetary Sciences(all)
- Space and Planetary Science
- Earth and Planetary Sciences(all)
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In: Advances in space research, Vol. 47, No. 2, 25.06.2010, p. 229-238.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - GNSS receiver clock modeling when using high-precision oscillators and its impact on PPP
AU - Weinbach, U.
AU - Schön, S.
N1 - Funding information: This work is funded by the Deutsche Forschungsgemeinschaft (DFG) in collaboration with the centre for QUantum Engineering and Space Time research (QUEST), Hannover.
PY - 2010/6/25
Y1 - 2010/6/25
N2 - Processing data from Global Navigation Satellite Systems (GNSS) always requires time synchronization between transmitter and receiver clocks. Due to the limited stability of the receiver's internal oscillator, the offset of the receiver clock with respect to the system time has to be estimated for every observation epoch or eliminated by processing differences between simultaneous observations. If, in contrast, the internal oscillator of the receiver is replaced by a stable atomic clock one can try to model the receiver clock offset, instead of estimating it on an epoch-by-epoch basis. In view of the progress made in the field of high-precision frequency standards we will investigate the technical requirements for GNSS receiver clock modeling at the carrier phase level and analyze its impact on the precision of the position estimates. If we want to take advantage of the frequency stability provided by a high-performance oscillator in combination with a GNSS receiver we have to ensure that the signal delays inside the receiver hardware remain constant. Therefore, we have analyzed the relative receiver clock offsets for a number of GNSS receivers that derive their frequency reference from a common oscillator. Based on experimental data of an exemplary pair of geodetic receivers we show that the noise from variations of the hardware delays in the receiver electronics does not exceed the receiver clock noise (5 ps RMS) when all environmental effects are carefully controlled. By analyzing the elements of the parameter covariance matrix for a simple case of point positioning, the impact of GNSS receiver clock modeling on kinematic and static solutions is studied. Furthermore, we demonstrate the suitability of a single quadratic polynomial to model a receiver clock that is locked to the frequency of an active hydrogen maser for periods up to 24 h. Based on simulated and real GNSS data it is shown that receiver clock modeling improves the RMS of the height component of a kinematic Precise Point Positioning (PPP) by up to 70%, whereas for the static case the gain is almost negligible.
AB - Processing data from Global Navigation Satellite Systems (GNSS) always requires time synchronization between transmitter and receiver clocks. Due to the limited stability of the receiver's internal oscillator, the offset of the receiver clock with respect to the system time has to be estimated for every observation epoch or eliminated by processing differences between simultaneous observations. If, in contrast, the internal oscillator of the receiver is replaced by a stable atomic clock one can try to model the receiver clock offset, instead of estimating it on an epoch-by-epoch basis. In view of the progress made in the field of high-precision frequency standards we will investigate the technical requirements for GNSS receiver clock modeling at the carrier phase level and analyze its impact on the precision of the position estimates. If we want to take advantage of the frequency stability provided by a high-performance oscillator in combination with a GNSS receiver we have to ensure that the signal delays inside the receiver hardware remain constant. Therefore, we have analyzed the relative receiver clock offsets for a number of GNSS receivers that derive their frequency reference from a common oscillator. Based on experimental data of an exemplary pair of geodetic receivers we show that the noise from variations of the hardware delays in the receiver electronics does not exceed the receiver clock noise (5 ps RMS) when all environmental effects are carefully controlled. By analyzing the elements of the parameter covariance matrix for a simple case of point positioning, the impact of GNSS receiver clock modeling on kinematic and static solutions is studied. Furthermore, we demonstrate the suitability of a single quadratic polynomial to model a receiver clock that is locked to the frequency of an active hydrogen maser for periods up to 24 h. Based on simulated and real GNSS data it is shown that receiver clock modeling improves the RMS of the height component of a kinematic Precise Point Positioning (PPP) by up to 70%, whereas for the static case the gain is almost negligible.
KW - Atomic clocks
KW - Clock modeling
KW - GNSS
KW - Hardware delays
KW - PPP
UR - http://www.scopus.com/inward/record.url?scp=78650707090&partnerID=8YFLogxK
U2 - 10.1016/j.asr.2010.06.031
DO - 10.1016/j.asr.2010.06.031
M3 - Article
AN - SCOPUS:78650707090
VL - 47
SP - 229
EP - 238
JO - Advances in space research
JF - Advances in space research
SN - 0273-1177
IS - 2
ER -