The ALOS mission featured a systematic observation strategy which comprised pre-launch, systematic global observation plans for all three instruments. The strategy was implemented as a top-level foreground mission and with a priority level second only to that of emergency observations.
The observation strategy was developed by JAXA EORC and aimed to provide spatially and temporally consistent, multi-seasonal global coverage, on a repetitive basis, with all three sensors, during the life-time of the ALOS satellite. It was foreseen to result in a comprehensive and homogeneous global archive of PALSAR, PRISM and AVNIR-2 data, in which a consistent time-series for data could be found for any arbitrary point or region on Earth.
At the time of launch, such consistent data archives only
existed for coarse resolution satellites.
Read more on JAXA website
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