Digital Technique of Complex Amplitude Multifrequency Scanning for Ionospheric Spatial Doppler Measurements.

摘要

Ionospheric motions were measured applying a new spectral analysis method and a correspondingly developed digital data acquisition system. Spectral analysis of ionospheric echoes received with three spaced antennas separates the angles of arrival of waves simultaneously reflected from different areas in the ionosphere generally producing distinguishable Doppler shifts. Measurements in Goose Bay, Labrador and Eglin,Florida show the motion of two different structures;the motion of the medium scale structure is revealed by the time progression of the reflecting areas that form narrow bands,while the measured Doppler shift indicates direction and speed of the small scale irregularities. The Complex Amplitude Multifrequency Scanning chassis was incorporated into a Digisonde to provide digital amplitude and phase data for three antennas and for up to six selectable frequencies in the band from 0.5to 16MHz. (Author)