Revisiting GRACE Follow-On KBR Antenna Phase Center Calibration by Addressing Multipath Noise
The Gravity Recovery and Climate Experiment Follow-On (GRFO) mission precisely measures the inter-satellite range between the centers of mass of its twin satellites to map the earth’s gravity field. The baseline ranging measurement is achieved using the K-band ranging (KBR) system, which is sensitiv...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-01-01
|
| Series: | Remote Sensing |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2072-4292/17/3/353 |
| _version_ | 1826805904704536576 |
|---|---|
| author | Haosi Li Peng Xu He Tang Shuang Yi |
| author_facet | Haosi Li Peng Xu He Tang Shuang Yi |
| author_sort | Haosi Li |
| collection | DOAJ |
| description | The Gravity Recovery and Climate Experiment Follow-On (GRFO) mission precisely measures the inter-satellite range between the centers of mass of its twin satellites to map the earth’s gravity field. The baseline ranging measurement is achieved using the K-band ranging (KBR) system, which is sensitive to satellite attitude variations caused by the offset between the satellite center of mass and the KBR antenna phase center. Accurate decoupling of the KBR range from attitude variations requires precise determination of the KBR’s antenna offset vectors (AOVs). To address this, GRFO conducted eight KBR calibration maneuvers on 17 and 28 September 2020. However, these maneuvers exaggerated the impact of microwave multipath noise, complicating AOV estimation. Existing studies have not fully mitigated this noise. This study introduces a new frequency-domain method to estimate AOVs by leveraging double-difference signals and analyzing their spectral characteristics, along with those of the KBR range during calibration maneuvers, to suppress multipath noise. Our recalibrated AOVs achieve good alignment between the KBR and laser ranging interferometer (LRI) ranging signals. We validate our recalibrated AOVs by comparing the residuals between the LRI and KBR ranging signals corrected using both recalibrated AOVs and documented AOVs. The results show that, for the majority (58.4%) of the analyzed period (from January 2020 to June 2023), the residuals corrected by the recalibrated AOVs are closer to the LRI ranging signal. These findings demonstrate the effectiveness of the proposed method in addressing multipath noise and improving the accuracy of KBR range measurements. This work provides a framework for future gravity missions requiring precise calibration of multipath effects in inter-satellite ranging systems. |
| first_indexed | 2025-03-17T02:17:52Z |
| format | Article |
| id | doaj.art-480ca394e1b14a8e88d8ec6754122285 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2025-03-17T02:17:52Z |
| publishDate | 2025-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-480ca394e1b14a8e88d8ec67541222852025-02-12T15:07:32ZengMDPI AGRemote Sensing2072-42922025-01-0117335310.3390/rs17030353Revisiting GRACE Follow-On KBR Antenna Phase Center Calibration by Addressing Multipath NoiseHaosi Li0Peng Xu1He Tang2Shuang Yi3National Key Laboratory of Earth System Numerical Modeling and Application/College of Earth and Planetary Sciences, University of Chinese Academy of Sciences (UCAS), Chinese Academy of Sciences, Beijing 101408, ChinaCenter for Gravitational Wave Experiment, National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, ChinaState Key Laboratory of Precision Geodesy, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430077, ChinaNational Key Laboratory of Earth System Numerical Modeling and Application/College of Earth and Planetary Sciences, University of Chinese Academy of Sciences (UCAS), Chinese Academy of Sciences, Beijing 101408, ChinaThe Gravity Recovery and Climate Experiment Follow-On (GRFO) mission precisely measures the inter-satellite range between the centers of mass of its twin satellites to map the earth’s gravity field. The baseline ranging measurement is achieved using the K-band ranging (KBR) system, which is sensitive to satellite attitude variations caused by the offset between the satellite center of mass and the KBR antenna phase center. Accurate decoupling of the KBR range from attitude variations requires precise determination of the KBR’s antenna offset vectors (AOVs). To address this, GRFO conducted eight KBR calibration maneuvers on 17 and 28 September 2020. However, these maneuvers exaggerated the impact of microwave multipath noise, complicating AOV estimation. Existing studies have not fully mitigated this noise. This study introduces a new frequency-domain method to estimate AOVs by leveraging double-difference signals and analyzing their spectral characteristics, along with those of the KBR range during calibration maneuvers, to suppress multipath noise. Our recalibrated AOVs achieve good alignment between the KBR and laser ranging interferometer (LRI) ranging signals. We validate our recalibrated AOVs by comparing the residuals between the LRI and KBR ranging signals corrected using both recalibrated AOVs and documented AOVs. The results show that, for the majority (58.4%) of the analyzed period (from January 2020 to June 2023), the residuals corrected by the recalibrated AOVs are closer to the LRI ranging signal. These findings demonstrate the effectiveness of the proposed method in addressing multipath noise and improving the accuracy of KBR range measurements. This work provides a framework for future gravity missions requiring precise calibration of multipath effects in inter-satellite ranging systems.https://www.mdpi.com/2072-4292/17/3/353GRACE Follow-Onantenna offset correctionK-band rangingmultipath noise |
| spellingShingle | Haosi Li Peng Xu He Tang Shuang Yi Revisiting GRACE Follow-On KBR Antenna Phase Center Calibration by Addressing Multipath Noise Remote Sensing GRACE Follow-On antenna offset correction K-band ranging multipath noise |
| title | Revisiting GRACE Follow-On KBR Antenna Phase Center Calibration by Addressing Multipath Noise |
| title_full | Revisiting GRACE Follow-On KBR Antenna Phase Center Calibration by Addressing Multipath Noise |
| title_fullStr | Revisiting GRACE Follow-On KBR Antenna Phase Center Calibration by Addressing Multipath Noise |
| title_full_unstemmed | Revisiting GRACE Follow-On KBR Antenna Phase Center Calibration by Addressing Multipath Noise |
| title_short | Revisiting GRACE Follow-On KBR Antenna Phase Center Calibration by Addressing Multipath Noise |
| title_sort | revisiting grace follow on kbr antenna phase center calibration by addressing multipath noise |
| topic | GRACE Follow-On antenna offset correction K-band ranging multipath noise |
| url | https://www.mdpi.com/2072-4292/17/3/353 |
| work_keys_str_mv | AT haosili revisitinggracefollowonkbrantennaphasecentercalibrationbyaddressingmultipathnoise AT pengxu revisitinggracefollowonkbrantennaphasecentercalibrationbyaddressingmultipathnoise AT hetang revisitinggracefollowonkbrantennaphasecentercalibrationbyaddressingmultipathnoise AT shuangyi revisitinggracefollowonkbrantennaphasecentercalibrationbyaddressingmultipathnoise |