This paper investigates the capability of a miniaturized radar sensor developed for mini Unmanned Aerial Systems (UAS) and Micro Aerial Vehicles (MAVs) to provide the flying platform with radar-based navigation and sense-and-avoid (SAA) functions. A radar sensor based on Frequency Modulated Continuous Wave (FMCW) technology developed by IMST GmbH is therefore exploited both for tracking, SAA, and Synthetic Aperture Radar (SAR) oriented acquisitions. Main challenges related with data interpretation are analyzed and the results suggest that valuable data for each envisaged application can be obtained.