A new techniqne that significantly minimizes the aliasing error encountered in the conventional use of the fast Fourier transform (FFT) algorithms for the efficient evaluation of Fourier transforms of spatially limited functions (such as those that occur in the radiation pattern analysis of reflector antennas and planar near field to far field (NF-FF) transformation) is presented and illustrated through a typical example. Employing this techniqne and a discrete Fourier series (DFS) expansion for the integrand, a method for computing the radiation integrals of reflector antennas and planar NF-FF transformation integrals at arbitrary observation angles with optimum use of computer memory and time is also described. Copyright © 1984 by The Institute of Electrical and Electronics Engineers, Inc.

M. S. Narasimhan

M. Karthikeyan

MATHEMATICAL TRANSFORMATIONS - Fast Fourier Transforms

Antennas

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IIT Madras

Evaluation of Fourier transform integrals using FFT with improved accuracy and its applications

IEEE Transactions on Antennas and Propagation

An efficient technique for probe-directivity uncompensated spherical near-field to far-field (NF-FF) transformation is presented. The technique proposed does not make use of the spherical vector wave functions (SVWF) in the conventional manner, but seeks to obtain the NF-FF transformation exactly, viewing it as an electromagnetic scattering problem. The problem is formulated by considering the NF-FF transformation, when the FF observation points are restricted to a single ϕ plane at a time. The analytical expressions derived toward this end assume a considerably simplified form offering a high computational efficiency. The proposed technique is validated by considering arrays as test antennas with a maximum dimension of 150 X. Based on the principles employed for the spherical NF-FF transformation, an efficient technique for computing the FF patterns of a perfectly conducting scatterer illuminated by an arbitrary source using the technique of physical optics (PO) is also developed. In order to validate this, typical numerical computations are performed and the results obtained are discussed. © 1989 IEEE

An Efficient Technique for Spherical Near-Field to Far-Field Transformation and Evaluation of Far Fields of Perfectly Conducting Scatterers

Applications of probe-compensated near-field measurements

The extended boundary condition solution of the dipole antenna of revolution

Analysis of Reflector Antennas

Performance Analysis

Proceedings of the IEEE

Matrix formulation of electromagnetic scattering

Evaluation of Fourier Transform Integrals Using FFT with Improved Accuracy and its Applications

Journal	IEEE Transactions on Antennas and Propagation
ISSN	0018926X
Open Access	No