Calculated 70-meter antenna performance for offset L-band and C-band feeds

摘要

A series of calculations that were carried out in order to determine the performance of the new dual-shaped 70 meter antenna for feeds that are displaced from the focal ring are summarized. Calculations were carried out at 1.68 GHz (L-band) and 5.0 GHz (C-band) for a number of feed/subreflector configurations. The effects of feed displacement, feed pointing angle, subreflector tilt, and lateral subreflector movement are summarized. Of specific interest are gain, beam squint, and spillover noise temperature for each of the feed/subreflector configurations described above.