Analytic Transient Analysis of Radiation From Ellipsoidal Reflector Antennas for Impulse-Radiating Antennas Applications

Abstract

A time-domain (TD) analysis of ellipsoidal reflector antennas is presented to predict the transient scattered fields when it is illuminated by a cosine-tapered and transient-step feed radiation whose phase center is located at the nearby focus. A transient-step function of the feed's radiation is considered because it will produce an impulsive response near the second focus of the reflector as interested in the applications of impulse-radiating antennas. This TD solution is in a closed form and remains valid both near and far from the reflector, and can be used via the convolution theorem to efficiently obtain the early time transient fields generated by the same ellipsoidal reflector antenna when it is illuminated by a realistic finite-energy pulse which emanates as a spherical wave from the focus. Numerical results are presented for the transient fields both near and far from the reflector.Index Terms-Aperture integration, ellipsoidal reflector antennas, near-field focus and impulse-radiating antenna, time domain, transient analysis.

Quasi-optical analysis of a double reflector microwave antenna system

“…Further studies are necessary to analyze the power transfer efficiency and improve the model, alongside to simulations to all the process that exhaust the parameter space and allow proper optimization. A case study of a system with a double ellipsoidal mirror is also being considered [38,39], although some analysis is already presented here.…”

Analytic Analysis of Transient Radiation From Phased Array Antennas in the Near- and Far-Field Focus Applications

“…Thus (19) becomes two points at (27) unless (or ). Otherwise, the aperture plane will be tangent to the degenerated cone of the hyperbolic surface as illustrated in Fig.…”

“…One employs the following parameter transformation: (29) and makes (17) become (30) where the transformation Jacobian, , can be found by [24], [25], [27] …”

“…Due to the sophisticated complexity in the analytical analysis in TD, most of past TD EM analysis tends to employ TD numerical techniques, such as finite difference time domain (FDTD) [11] and TD integral approaches [12], which provided exact solutions, but suffered from computational inefficiency to treat the radiations problems of electrically large antennas. Thus, it remains attractive to develop quasi-analytical TD solutions [13]- [27] with simple and closed forms, which have the advantage of providing physical interpretations of wave behaviors. Examples include the developments of TD uniform geometrical theory of diffraction (TD-UTD) [19]- [22], physical theory of diffraction (TD-PTD) [23], physical optics (TD-PO) [24], [25] and TD aperture integration (TD-AI) [26], [27] techniques that were obtained by using either a direct inverse Laplace transform [24] or an analytical time transform (ATT) [20]- [22], [25] of the corresponding FD formulations [28].…”

“…Thus, it remains attractive to develop quasi-analytical TD solutions [13]- [27] with simple and closed forms, which have the advantage of providing physical interpretations of wave behaviors. Examples include the developments of TD uniform geometrical theory of diffraction (TD-UTD) [19]- [22], physical theory of diffraction (TD-PTD) [23], physical optics (TD-PO) [24], [25] and TD aperture integration (TD-AI) [26], [27] techniques that were obtained by using either a direct inverse Laplace transform [24] or an analytical time transform (ATT) [20]- [22], [25] of the corresponding FD formulations [28]. These solutions are limited to the transient analysis of antenna radiation with scattering mechanisms such as the reflector antennas, and are not applicable to the current situation of direct antenna radiation from a time-delayed array.…”