Evaluation of Coherence Properties of Signals of Opportunity for Snow Measurement

Snow water storage in land is a critical parameter of the water cycle. In this study, we develop methods for estimating reflectance from bistatic scattering of digital communication Signals of Opportunity (SoOp) across the available microwave spectrum from VHF to Ka band and show results from proof-of-concept experiments at the Fraser Experimental Forest, Colorado to acquire measurements to relate the SoOp phase and reflectivity to a snow-covered soil surface.

Since 2016, we have conducted a field experiment using VHF/UHF-band illuminating sources to detect Snow Water Equivalent (SWE) and surface reflectivity. The amplitude of the reflectivity showed sensitivity to the wetness of snow pack and ground reflectivity while the phase showed sensitivity to SWE. This idea is scalable to space provided the signal is coherent. Experiments on Unmanned Air Vehicle (UAV) and airplane is being conducted to evaluate the coherence properties of these signals. Results from these experiments will be presented. To gain an understanding on coherence properties from space, data from L-band will be analyzed and presented.