For digital transformation (DX) of infrastructure management, incorporation with ICT technology and AI technology is actively studied. Wide range of application of satellite for infrastructure management is explored in this issue. Especially SAR images are shown to be useful for monitoring of infrastructure, such as bridges, embankments or water leakage, as well as for management after large scale natural disasters.

JAXA has been developing infrastructure monitoring by satellite based synthetic aperture radar (SAR) using ALOS-2 satellite. By employing L-band SAR, high resolution measurement of 3m with measurement width of 50km is achieved. Since wave length of L-band is longer than that of X-band, L-band radar has higher transparency for cloud, rain or leaves. Relative displacement between satellite and surface are identified from phase lag between two observations. JAXA proposed screening method for ground inspection by automatic displacement variation detection using satellite SAR with measurement accuracy of mm order for 50km square area.

For disaster response decision making, information on the event and location is critical, and management of satellite observation scheduling specifying timing and area is required. However, difficulty arises especially for wide area disasters. In this paper, constellation management of multiple satellites considering characteristics of each satellite and minimization of time from request to information delivery are studied and applied to actual disasters.

Large amount of satellite images are provided from various organizations for Russian invation of Ukraine. The authors have started collaboration to construct satellite map of Ukraine by identifying camera shooting condition for each image and archiving. Since optical images are not available for cloudy wheather, the SAR images are employed and actual events are verified. Effetiveness of collective use and analysis of open data is demonstrated and furter development is expected to be promising.

Toyota City is replacing 40km of water pipelines annually, and effective and efficient renewal is required. AI based deterioriation prediction and diagnosis tool is introduced for prioritizing replacement. Satellite based SAR image with L-band is also incorporated to detect leakage from reflection properties. The accuracy of water leakage is 27%. Using this technology, required ground inspection length is redued from 2.210km to 257km, and further development and verification is inderway．

Optical images from satellite inherently include distortion and noise, which can be eliminated by appropriate calibration. The authors developed mirror array and placed for observation from satellites. Calibration for satellite SAR images are also studied, and accuracy using corner reflectors is verified, which can contribute to monitoring of infrastructure or natural disasters.

Satellite based SAR is employed for monitoring of infrastructure. Anomaly of motion of infrastructure is detected to specify objective for further inspection with LiDAR and hyperspectral measurement to reproduce in digital space. This technology is applied to detection of: change of land use and building; monitoring environmental pollution; monitoring of bridges, embankment, or ground; or airprt facilitiy management.

"AW3D " satellite based highly accurate three dimensional map covering the entire land area on the Earth is developed, which accuracy has been close to that of aerial photos. The accuracy enhancement was achieved thanks to the improvements of satellite image resolution, number of satellites and an innovative image processing technique using a large number of satellite images. Furthermore, the integration of the satellite 3D and ground sensor is studied to enhance the reality of 3D city model. AW3D achieves 50cm resolution 3D map over Japan and 2.5m resolution 3D map over the world, and has started the update of the map over Japan since 2022.