Abstract
Global Navigation Satellite Systems Reflectometry (GNSS-R) is an increasingly utilised remote sensing technique exploiting Earth reflections of navigation signals to sense water based essential climate variables (ECVs), with missions such as the recently launched ESA Scout HydroGNSS sensing variables such as inundation, soil moisture, and above ground biomass. Raw intermediate frequency (IF) data captured from previous GNSS missions has been used in preparation for HydroGNSS to study the impact of both the coherent integration time and interference artifacts in the creation of the main GNSS-R scientific output of a Delay Doppler Map (DDM). Within the main focus area of coherent integration time we find that there is an increase in SNR (Signal to Noise) </p><p>rather than 1 ms over all surfaces, with greater increase seen over coherently reflecting surfaces such as ice. In addition we have also observed increased vulnerability to interference at higher coherent integration times, with greater impact seen in GPS C/A signals than Galileo E1. We begin to explore how interference impacts DDM generation and new methods in how to replicate the increasingly present problem.