Comments on "Nondispersive waves: interpretation and causality", by P.T.M. Hillion [with reply]

Heyman and Felsen comment on a paper by Hillion (IEEE Trans. Antennas Propag., vol.AP-40, p.1031-5, 1992). Hillion gives a reply. The articles discuss nondiffracting wave objects and how they can be excited by physical aperture antennas.<
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