11:45 AM - 12:00 PM
[STT36-11] Development of ground-based radar interferometer for volcano deformation monitoring
Keywords:SAR, crustal deformation, voilcano
SAR interferometry using spaceborne SAR has been used as one of the general tools for detecting volcanic deformation. It is effective because spatially detailed deformation is obtained without ground observations. If volcano deformation can be detected with higher temporal resolution during active volcanic activity, it is expected to lead to a more detailed understanding of the volcanic activity mechanism. However, it has a disadvantage that the temporal resolution is limited to the satellite recurrence period. Therefore, we are researching on the use of ground-based radar interferometers that can illuminate radar wave from the ground and investigate crustal movements frequently for volcanic observation.
We have installed LiSA mobile k09 (synthetic aperture radar type) and GAMMA GPRI2 (real aperture radar type) using Ku-band radar waves at the Asama volcano and are continuing their operations for 5 years. After the start of operation, a very small eruption occurred at the Asama volcano, but no significant crustal movement was detected. On the other hand, atmospheric disturbances are prominent, and phase changes that exceed one cycle in a few minutes are often detected by real aperture radar. In such situation, processing of the synthetic aperture radar often fails. Its solution is difficult and this problem is one of the disadvantages of ground-based synthetic aperture radar.
We are also developing a portable synthetic aperture radar which can be used in a campaign observation during the time that volcanic activity increases. This synthetic aperture radar can select observation methods moving the antenna on the rail (GBSAR type), by vehicle-mounted (Car-borne type), and by hand (Man-borne type). Regarding the GBSAR and the Car-borne types, it has been confirmed that appropriate coherence can be obtained by repeat-pass observations. In the future, we will improve this sensor through experiment measurements in volcanoes and attempt to detect crustal deformation.
We have installed LiSA mobile k09 (synthetic aperture radar type) and GAMMA GPRI2 (real aperture radar type) using Ku-band radar waves at the Asama volcano and are continuing their operations for 5 years. After the start of operation, a very small eruption occurred at the Asama volcano, but no significant crustal movement was detected. On the other hand, atmospheric disturbances are prominent, and phase changes that exceed one cycle in a few minutes are often detected by real aperture radar. In such situation, processing of the synthetic aperture radar often fails. Its solution is difficult and this problem is one of the disadvantages of ground-based synthetic aperture radar.
We are also developing a portable synthetic aperture radar which can be used in a campaign observation during the time that volcanic activity increases. This synthetic aperture radar can select observation methods moving the antenna on the rail (GBSAR type), by vehicle-mounted (Car-borne type), and by hand (Man-borne type). Regarding the GBSAR and the Car-borne types, it has been confirmed that appropriate coherence can be obtained by repeat-pass observations. In the future, we will improve this sensor through experiment measurements in volcanoes and attempt to detect crustal deformation.