As is known to all, the highest-resolution military optical remote sensing satellite in the world is the kh-11 (keyhole series) and kh-12 series reconnaissance satellite developed by the United States. The resolution is as high as 0.08m to 0.15m. It is said that combined with the super-resolution image processing software, the vehicle license plate number of ground vehicles can be distinguished under good sunlight.
Due to its huge size (the diameter of the main mirror alone is 2.4 meters, the length is about 13 meters, the weight of its satellites is up to 6 10 tons, the launch weight is up to 23 tons), the flight altitude is low (200 to 1000 km), the cost and operating costs are extremely expensive.
With the end of the cold war, there is a growing demand for high quality geospatial data using satellite remote sensing images in all walks of life.