3:30 PM - 5:00 PM
[SGD01-P10] Differences in receiving antenna phase characteristics of GPS and GLONASS and their effects (2)
Keywords:GNSS, phase characteristics, GEONET
At the JPGU meeting last year, we showed in a preliminary analysis that applying a phase center correction (PCC) model for GPS to a baseline analysis based on GLONASS data for GEONET stations may result in a systematic bias of the order of cm from the baseline solution based on GPS data. Preliminary analysis has shown that the difference depends not only on the antenna model but also on the type of antenna monument, and that the difference is reduced by applying a phase characteristic model that has been calibrated using GLONASS data. In this study, phase characteristics for GLONASS were calibrated for 20 of the antenna and monument combinations of GEONET, and the effect was evaluated by applying these to GEONET's F5 (test) analysis.
The calibration observations were conducted from January to March 2022 on the roof of the Geodetic Survey Center of the Geospatial Information Authority of Japan (GSI) for combinations of four types of multi-GNSS antennas and five types of antenna mounts that are used in GEONET stations. The data were analyzed using BERNESE ver. 5.0 to estimate the PCC model of the L1 and L2 bands for GPS and GLONASS, respectively.
The GLONASS data from the calibration observation were analyzed for the baselines applying the obtained PCC models and using the same settings as for the F5 analysis. The results showed that the bias of the height component when applying the PCC model for GPS depends on the combination of antenna and mount types, and that its magnitude exceeds 2 cm at the maximum, and that the biases are improved by applying the PCC model for GLONASS. It was confirmed that the bias was improved by applying the model for GLONASS. Furthermore, the obtained GNSS-specific PCC models were applied to analyze all GEONET stations with the F5 (test) analysis strategy for two months of data (DOY 170 - 230, 2021). The results shows the improvement of the consistency between the GLONASS and GPS solutions: the mean and standard deviation of the biases of the height components of both solutions were reduced from 13.0 mm to 3.8 mm and from 9.5 mm to 6.3 mm, respectively.
The calibration observations were conducted from January to March 2022 on the roof of the Geodetic Survey Center of the Geospatial Information Authority of Japan (GSI) for combinations of four types of multi-GNSS antennas and five types of antenna mounts that are used in GEONET stations. The data were analyzed using BERNESE ver. 5.0 to estimate the PCC model of the L1 and L2 bands for GPS and GLONASS, respectively.
The GLONASS data from the calibration observation were analyzed for the baselines applying the obtained PCC models and using the same settings as for the F5 analysis. The results showed that the bias of the height component when applying the PCC model for GPS depends on the combination of antenna and mount types, and that its magnitude exceeds 2 cm at the maximum, and that the biases are improved by applying the PCC model for GLONASS. It was confirmed that the bias was improved by applying the model for GLONASS. Furthermore, the obtained GNSS-specific PCC models were applied to analyze all GEONET stations with the F5 (test) analysis strategy for two months of data (DOY 170 - 230, 2021). The results shows the improvement of the consistency between the GLONASS and GPS solutions: the mean and standard deviation of the biases of the height components of both solutions were reduced from 13.0 mm to 3.8 mm and from 9.5 mm to 6.3 mm, respectively.