@ARTICLE{ :/content/journals/10.1049/ip-map_19982068, author = {E.M. Warrington}, keywords = {reflection points;ionospherically propagated HF radio channel sounding signals;directional characteristics;pulsed channel sounding signal;time delay component;Doppler shifts;Doppler component;transauroral path;scattering;disturbances;high latitude paths;polar cap path;ionospheric irregularities;}, ISSN = {1350-2417}, language = {English}, abstract = {The author presents measurements of the directional characteristics of the Doppler and time delay components of a pulsed channel sounding signal received over two high latitude paths. A variation in bearing with Doppler frequency was frequently evident, an effect attributed to Doppler shifts imposed on the signal when scattered from ionospheric irregularities drifting across the reflection points. For a transauroral path, for which the ionospheric reflection points were subauroral, standard deviations of up to ~ 2.5° were observed in the azimuthal power distribution of the received energy. Much greater disturbances with azimuthal standard deviations of up to ~35° were recorded on signals received over a path contained entirely within the polar cap path.}, title = {Observations of the directional characteristics of ionospherically propagated HF radio channel sounding signals over two high latitude paths}, journal = {IEE Proceedings - Microwaves, Antennas and Propagation}, issue = {5}, volume = {145}, year = {1998}, month = {October}, pages = {379-385(6)}, publisher ={}, copyright = {© IEE}, url = {https://digital-library.theiet.org/;jsessionid=izgbdevdgimm.x-iet-live-01content/journals/10.1049/ip-map_19982068} }