Ludi Tance-1 is China’s first satelliteformationsystem for deformation measurement and monitoringwithdifferential interferometry SAR technology. As a part of the twin satellites for land-observation, theL-SAR 01Bsatellite was sent into a sun-synchronous orbit on 27th Feb, 2022 at 7:44 a.m., to jointly explore the earth with L-SAR 01A.Shanghai Jiao Tong Universityserved as the deputy chief design engineering department and developed the core technology of satellite formation to guarantee the precision measured in millimetres for Ludi Tance-1.

As the first launched satellite followingChina’s Nationaldevelopment planofMedium and Long-Term Development Strategy of China’s civil Space Infrastructure,Ludi Tance-1 satellite, together with the twin satellite, has demonstrated its potential as repeat-pass differential interferometric deformation measurement and topographic mapping tools, which used a brand-new formation technology developed byShanghai Jiao Tong University. The Ludi Tance satellites facilitate land mapping and resource monitoring to help the government give a quicker respond to all kinds of major events and geological disasters such as earthquakes and landslides. China heavily relies on foreign countries to attain SAR data, but now with the competitive Ludi Tance-1, we can change the situation.

Shao Xiaowei, the research fellow of theSchool of Aeronautics and Astronautics,Shanghai Jiao Tong University,serves as the deputy chief designer of Ludi Tance-1 satellite.His group mainly designed the satellite formation configuration, frozen repeatorbit pattern,andmission planning and scheduling.They were also responsible for evaluating the baseline performance of the satellite height-measurement anddeformation-monitoring beforethe lift-off. Their work secures a repetitive monitoring technology with 100m precision in land deformation and a long-term interference mapping tool in land observation.Chen Junli, the chief designer ofLudi Tance-1, has spoken highly of the contribution made byShanghai Jiao Tong University. He said their research outcomelays a good foundation for developing SAR satellite and enables China to conductmore formation-based technological innovation.

So far, Shao Xiaowei and his group have proposed a scientific and complete theoretical framework for satellite formation system, meeting the requirements for national major technical equipment and projects in the area of distributed satellite system for microwave mapping. They have also made a lot of original research achievements on the on-orbit application of satellite formation which benefit the capture and process of satellite data.