04940989 is referenced by 26 patents and cites 2 patents.

A method of feeding a high impedance point of an antenna, such as the end of a 1/2 wave radiator. A resonant cavity is used for making an impedance match between the antenna and the feed line and forming a decoupling mechanism for forming the high impedance. Simultaneously, the cavity choke is formed with the open end facing toward the feed point for allowing a feed point impedance transformation between the feed line and the high impedance at the end of the 1/2 wave element and forming a high impedance point by its resonance for preventing the feed from flowing down along the outer surface of the choke and feed line.

Title
Apparatus and method for matching radiator and feedline impedances and for isolating the radiator from the feedline
Application Number
856236
Publication Number
4940989
Application Date
December 12, 1988
Publication Date
July 10, 1990
Inventor
Richard A Austin
Powder House Rd., R.D. #1, Sandown, 03873
NH, US
Agent
Ross Ross & Flavin
IPC
H01Q 9/40
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