Indoor Drone Propeller Speed Estimation Using Wi-Fi CSI

With the evolution of drone technology, its range of applications has expanded to include logistics, surveillance, inspection, agriculture, and other indoor applications. However, improving drone control accuracy has become a major challenge, and accurate knowledge of propeller rotation speed is essential to solving this problem.
In this study, we propose a method for estimating propeller rotation speed using Wi-Fi Channel State Information (CSI). This method has the advantage that it does not require any additional hardware because it utilizes the Wi-Fi equipment installed in the drone.
The proposed method applies a Fast Fourier Transform (FFT) to CSI amplitude data to perform frequency analysis and peak detection. To cope with the non-uniform observation intervals of CSI, a resampling process is introduced to improve the estimation accuracy.
In the future, we plan to evaluate the system on actual drones to achieve fast RPM estimation on the millisecond order.