Accession Number : ADA138557

Title :   Focal Region Characteristics of Focused Microwave Array Antennas.

Descriptive Note : Final rept.,

Corporate Author : HANSEN (R C) INC TARZANA CALIF*

Personal Author(s) : Hansen,R C

PDF Url : ADA138557

Report Date : 09 Sep 1983

Pagination or Media Count : 105

Abstract : Fields in the focal region of a focused microwave aperture or array antenna are examined thru detailed calculations. Transverse near field patterns are well behaved with only slightly higher closest sidelobes, and with a rapid sidelobe falloff. Peak axial power density available from an aperture is a function only of distance, but the relationship is non-linear. This relationship and simple formulas alloy system tradeoffs of aperture size, frequency, focal distance and peak power density to be made. Effects of aperture amplitude taper are investigated: uniform excitation gives comparable axial and transverse subsidiary lobes, and is probably the best choice. Taylor tapers give low sidelobes but high forelobes and aftlobes, plus a modest gain degradation. Inverse tapers give low forelobes and aftlobes but very high sidelobes and large gain degradation. A brief comparison of Gaussian, Romberg, and summation calculation methods is given. (Author)

Descriptors :   *Antenna arrays, *Focusing, *Sidelobes, *Microwave equipment, *Antenna apertures, Near field, High power, Sizes(Dimensions), Computer programs, Range(Distance), Transverse, Computations, Low level, Peak values, Degradation, Density, Power, Patterns, Axes, Gain, Apertures, Excitation

Subject Categories : Electrical and Electronic Equipment
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE