Achievement of pencil-beam radiation from a TM/sub 01/ mode circular waveguide source

A method employing appropriately placed parallel-metallic plates in the aperture of a TM/sub 01/ mode circular waveguide source so as to have it produce pencil-beam radiation is described and analyzed. Programmed computations, with experimental verification, are given for the case of a C-Band TM/sub 01/ source flared out to a conical horn so as to produce moderate (22 dBi) gain. Means of extending the method to achieve higher gains (40 dBi to 60 dBi) and to modify the plate arrangement so as to produce the same effect with a TE/sub 01/ mode are briefly outlined.>