Simultaneous observations of radio wave frequency and intensity fluctuations for estimates of solar wind speed Original Research Article

A new method is developed for solar wind speed measurements based on simultaneous observations of radio wave temporal intensity and frequency fluctuations. An estimate of the solar wind convection velocity is obtained from a combination of the frequency (Doppler) fluctuation spectral power at low fluctuating frequency and the power in the flat part of the intensity scintillation spectra below the Fresnel frequency. This new technique was applied to measurements taken during the Ulysses spacecraft coronal sounding experiment in 1991. Comparison of the speed estimates with earlier ones derived from simultaneous Doppler scintillation measurements at widely-spaced ground stations shows a fairly good agreement.