Frequency Stability Evaluation of SDR Platforms Concerning Their Use in Doppler-Based Location Method

Signal Doppler frequency (SDF) is one of the methods for locating radio emitters based on the Doppler effect. In this case, the SDF accuracy is closely related to the accuracy of determining the Doppler frequency shift. Therefore, ensuring the high-frequency stability of the software-defined radio (SDR) platform, which is used in the location sensor, plays an important role. In this paper, we explore several widely-available SDR platforms that could be used in that sensor. Based on the accuracy of instantaneous frequency measurement over time, we evaluate the frequency stability parameter of each SDR platform. We conduct tests as a function of time for various environmental conditions.