Insights and Improvements in Signal Processing for UAS-Based Non-Cooperative P-Band Reflectometry

Signals-of-Opportunity (SoOp) has emerged as a solution to scenarios where radar capabilities are limited due to protected bandwidth or the requirement of a large transmitter antenna. Encouraged by the success of implementation in the L-band, SoOp for P-band is under investigation due to its capabilities of peering deeper into the soil and vegetation. This method has the potential for the retrieval of root-zone soil moisture (RZSM) and snow water equivalent (SWE), two variables identified as priorities in the 2017-2027 Decadal Survey for Earth Science and Applications from Space. An uncrewed aerial system (UAS) based SoOp-reflectometry system has previously been implemented to exploit the capabilities of this emerging approach with a limited budget. In this paper, methodologies and preliminary results of surface reflectivity retrieval using the UAS-based system have been described and limitations affecting the current system have been identified.