Comparison of solar wind speed estimates from nearly simultaneous IPS observations at 327 and 111 MHz.

Results are presented of a comparison between solar wind speed estimates made using the time delays between 3 pairs of 327 MHz antennas at ISEE and estimates made by modeling the temporal power spectra observed with the 111 MHz BSA antenna at LPI. The observations were made for 6 years in the descending phase of solar cycle 24. More than 100 individual records were obtained for the compact source 3C48 and the extended and anisotropic source 3C298. The correlation between the daily speed estimates from 3C48 is 50%. Their annual averages agree within the error estimates and show the expected solar cycle variation. However the correlation between speeds from 3C298 is only 25% and their annual averages do not agree well. We investigate possible causes of this bias in the 3C298 estimated speeds.