Separation of modes by Doppler filtration

The propagation of decametric radio waves in the atmosphere exhibits a multimode signal structure that can lead to interference, signal distortion, and other undesirable effects. This paper presents an experimental study of the effectiveness of the Doppler filtering method in the mode separation of such radio waves. The effectiveness of the Doppler method is compared to that of the more traditional time-selection method. It is shown that the use of the Doppler method does not lead to unambiguous results.