A LOW-COST EARTH-OBSERVATION CAMERA WITH HIGH IMAGE PROCESSING CAPABILITY USING COTS TECHNOLOGIES

摘要

In recent years, remarkable advances have been made in remote sensing technology for Earth-observation satellites,as satellite-acquired images have found widespread use in both scientific research and commercial applications. Nationalprojects used to be the primary application of Earth-observation satellites, but with advancements in remote sensingtechnologies, commercial applications continue to emerge. Despite this development, satellite-acquired images are stillexpensive, which is one of the major barriers to the generation of new ideas for such applications in the private sector.Although the high cost of images is because of the high development cost of the satellites, these development costs areexpected to decrease. For this reason, we have rapidly developed a low-cost camera system to minimize the expenditureinvolved, based on our COTS-monitoring camera technologies, which uses IKAROS. We used COTS technologies suchas an FPGA, an imager used in digital cameras, and an open-source operating system. Based on this concept, the systemwas extended to capture high-resolution images using a high-resolution image sensor, a long focal-length optical system,and a high-performance processor. We have called this system CANAL-1, and we plan to demonstrate its performanceon the Earth and the Astronomical Observation Technology Demonstration Satellite, TSUBAME, whose launch isplanned for the end of 2012. During the demonstration using TSUBAME, we also plan to conduct a high-speed serialshooting mission that obtains images to simulate frame-by-frame video by performing serial shooting using CMG highspeedattitude control. The camera system is expected to capture images within a ground sample distance of 9.2 m at 500km, and the size of the optical and processing units are 177 × 75 × 77.5 mm and 110 × 60 × 37 mm, respectively. Weadapted Virtex4 to FPGA and used a PowerPC 405 operating at 400 MHz. In addition, we increased the RAM capacityto 256 MB while serial shooting, and we increased the image data capacity and Linux area for image processing.Furthermore, CANAL-1 uses a 2 GB NAND Flash for its main storage and 2 GB SD micro SD cards for sub-storage. Inthis paper, we introduce the basic concept of a low-cost Earth-observation camera and report the results of qualificationtests.