L- and S-Band Polarimetric Data Collections by ISRO's ASAR Instrument in Support of NISAR Ecosystems Algorithm Development

As a joint L- and S-band SAR satellite, the NISAR mission will be launched in the mid-2022 to early 2023 timeframe. While the majority of 12-day repeat cycle data collections on a global basis will be dual-polarized L-band only, over India, cal/val sites, and other regions around the world, a significant amount of two-frequency data will be collected as well. Limitations on the collection of two-frequency data are fundamentally due to thermal, power, and data rate constraints on the system. In order to support the co-development of algorithms for the dual-frequency data, during three data collection periods in 2019 and 2021, the Indian Space Research Organization's (ISRO) airborne instrument was flown by NASA within the United States. In this paper we summarize some of the analysis and interpretation of this data as collected by ASAR and processed by ISRO for Ecosystems and radio science applications.