A constellation of remote sensing small satellite systems has been developed for infrastructure monitoring in India by using SAR payload. The LEO constellation of the small satellites is designed in a way that can cover the entire footprint of India. Since India lies a little above the equatorial region, the orbital parameters are adjusted in a way that inclination of 36 degrees and RAAN varies from 70-130 degrees at a height of 600 km has been considered.
A total number of four orbital planes are designed, in which each orbital plane consists of three small satellites with 120-degrees true anomaly separation. Each satellite is capable of taking multiple-look images with the minimum resolution of 1 meter per pixel and swath width of approx.10 km. The multiple-look images captured by the SAR payload help in continuous infrastructure monitoring of our interested footprint area in India.
Each small satellite is equipped with a communication payload that uses X-band and VHF antenna, whereas the TT&C will use a high data-rate S-band transmitter. The paper presents only a coverage metrics analysis method of our designed constellation for our India footprint by considering the important metrics such as revisit time, response time, and coverage efficiency.
The result shows that the average revisits time for our constellation ranges from about 15-35 minutes, which is less than an hour, and the average response time for this iteratively designed constellation ranges from about 25-120 minutes, along with 100% coverage efficiency most of the time. Finally, it was concluded that each satellite has 70 kg of total mass and costs around $0.75 million to develop.
Research area: Robotics and autonomous systems
Authors: Roshan Sah, Raunak Srivastava, and Kaushik Das
Conference/event: Small Satellite Conference
Conference date: July, 2021