Johnson, A.M.; Landecker, T.L.; Johnson, T.; Veidt, B.G.; Du, X.: “Frequency Multiplexing Excitation Network for Ultra-Wideband Coaxial Waveguide Feeds.”, Electronics Letters, 2015, Vol. 51, Issue 20, p. 1580-1582, DOI: 10.1049/el.2015.2419
IET Digital Library:
http://digital-library.theiet.org/content/journals/10.1049/el.2015.2419