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

Abstract

Abstruct-We 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," we suggest source shaping in spacetime 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.

Parameterization of the Tilted Gaussian Beam Waveobjects

“…3). This type of Gaussian beam waveobjects exhibits frequency independent collimation (Rayleigh) lengths for which reason we previously termed it to be isodiffracting [37]. This iso-diffracting feature makes such waveobjects highly suitable for UWB radiation representations [11,13,14,38].…”

Pulsed Beam Expansion of Electromagnetic Aperture Fields

“…This type of windows gives rise to pulsed-quadratic beam waveobjects which exhibits frequency independent collimation (Rayleigh) distance and therefore are termed iso-diffracting [46]. The iso-diffracting nature makes these waveobjects highly suitable for UWB radiation representations [2,5,10,43,47].…”

“…Parameterization of the waveobjects in (46) can be found in [5]. Next, the electric field pulsed propagators are evaluated by inserting (46) into (32) and collecting the higher asymptotic order. Alternatively, the asymptotic electric field can be evaluated directly from (28).…”

TE and TM beam decomposition of time-harmonic electromagnetic waves

“…This type of windows gives rise to Gaussian beams that exhibit frequency-independent collimation (Rayleigh) lengths [see Eq. (49)] and, therefore, have been termed isodiffracting [37]. The isodiffracting feature makes these wave objects highly suitable for ultrawideband representations [2,4,10,[38][39][40].…”