Accession Number : AD0731179

Title :   Experimental Study of Coupled Thick Antennas,

Corporate Author : HARVARD UNIV CAMBRIDGE MASS CRUFT LAB

Personal Author(s) : Duff,Bob M.

Report Date : JUL 1971

Pagination or Media Count : 96

Abstract : The results of an experimental study of two identical, parallel, nonstaggered thick antennas are presented in this report. The term 'thick antenna' means a cylindrical dipole whose radius is significant compared to the free space wavelength of the exciting signal. Three thicknesses of antenna were used in the experiment: ka = 0.318, 0.639, and 0.877. Measurements were made of the apparent input admittance for both symmetric and antisymmetric drive, from which apparent self- and mutual admittances were computed. Both axial and transverse components of the current on the surface of the antennas were measured as functions of the cylindrical coordinates phi and z associated with the antenna. A complete description is given of the experimental system including the design of the antenna system, the arrangement for driving the antennas, a description of the measuring system, and a discussion of some of the problems encountered in carrying out the measurements. The variations of self- and mutual admittance as a function of spacing between antennas is shown with comparison to the behavior of thin antennas. Available theoretical results for the current distribution on coupled thick antennas are compared with the measured current distributions. (Author)

Descriptors :   (*ANTENNA ARRAYS, DIPOLE ANTENNAS), CYLINDRICAL BODIES, ADMITTANCE, COUPLING CIRCUITS, EXPERIMENTAL DATA

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE