English: Parabolic antenna types; three main types of parabolic antenna
Center fed: The feed antenna is at the focus of the antenna, on the beam axis.
Off-axis: The reflector is an asymmetric segment of a parabolic surface so the focus is off the beam axis, outside the beam area. This prevents the feed structure and its supports from blocking part of the beam.
Gregorian: The feed is located on or behind the center of the primary reflector. Its beam illuminates a concave secondary reflector at the focus, which reflects the beam back toward the primary reflector, This is mistakenly labelled "Cassegrain"; Cassegrain antennas have a convex secondary reflector.
Date
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Miikka Raninen
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Miikka Raninen
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