Certain considerations in aperture synthesis of ultrawideband/short-pulse radiation

The authors consider certain characteristics of the radiation from collimated, ultrawideband short-pulse aperture distributions. It is shown that an efficient radiation must account for the multifrequency nature of the field. Two alternative schemes for wideband aperture synthesis of an impulse-like radiation pattern are examined. The first, entitled the “iso-width aperture”, utilizes only temporal shaping of the excitation pulse. In the other, the “iso-diffracting aperture”, they suggest source shaping in space-time so that all the frequency components in the field have the same collimation distance. The “iso-diffracting” scheme yields higher directivity and more efficient pulsed radiation. Explicit examples for the pulsed source distribution and for the pulsed radiation patterns are presented, parametrized, and contrasted