“…For example, the Dregion ledge is easily visible to this radar (Mathews, 1984) as are D-region tidal winds (Mathews, 1976) and continuous "sporadic-E" (Morton et al, 1993;Mathews, 1998). Also, interestingly and uniquely for the incoherent scatter radars, near-field effects for this feed illuminating the 305 m dish are important up to approximately 300 km, resulting in significant corrections to the incoherent scatter radar equation (Breakall and Mathews, 1982;Shen and Brice, 1973). Early results using the new linefeed were given by Behnke and Harper (1973) and others.…”