Bradley J. Strait

Near fields of wire antennas by matrix methods

The method of moments [1], [2] is applied to wire antenna near-field problems. Within the general method, two computational procedures are developed. Results of these are compared with those of certain approximate analytical techniques and also with those of other investigators. A treatment for junctions is outlined. Examples are included for a single dipole antenna, for linear arrays of dipoles and also for loop and T -junction radiators.

Analysis and Design of Wire Antennas with Applications to EMC

The method of moments is applied to wire antennas. Antenna analysis and beam pattern synthesis methods are outlined. Constraints appropriate to problems of EMC can readily be introduced. Some of the subjects treated are coupling, parasitic effects, pattern synthesis, null placement, and gain maximization. Numerous examples are given to illustrate the theory.

On long wire antennas with multiple excitations and loadings

Matrix methods are applied for analysis and design of long thin-wire antennas with multiple excitations. It is shown how feed voltages can be determined to provide either specified values in a given pattern or maximum gain in some specified direction. Also, it is shown how passive loading can be included in the computational procedures and how in some simple cases load values can be computed to maximize gain in a given direction with respect to an unloaded wire of the same dimensions.

Antenna arrays with partially tapered amplitudes

A new technique is presented for linear array design based on a form of limited amplitude tapering. It is shown that desirable pattern characteristics can be achieved using an amplitude distribution that is uniform over all but a few of the outermost pairs of array elements, resulting in a partially uniform array. This method applies equally well to broadside and endfire arrays, and can be used to place pattern nulls in one or more specified directions or to eliminate virtually all radiation over one or more sectors of space. When compared with Dolph-Chebyshev arrays corresponding to the same sidelobe levels, partially uniform arrays provide a simpler excitation scheme in general and, in some cases, higher directive gain and a lower maximum-to-minimum excitation ratio. Both theoretical and experimental examples are given.

Constrained optimization of the gain of an array of thin wire antennas

Matrix methods are presented for maximizing the gain of an array of thin wire antennas subject to constrained sidelobe levels. The wires can be arbitrarily bent, and they can be excited or loaded at arbitrary points along their lengths.

Toward University-Industry Collaboration in Central New York

The establishment of new collaborative relationships between universities and industry, specifically the recent creation of centers for collaborative research at universities, is motivated by changes in federal policy for research funding. The Center for Advanced Technology in Computer Applications and Software Engineering (CASE Center) at Syracuse University was established under a new New York State program that reflects those changes. The Center is a consortium of 16 academic institutions in central New York pursuing complementary goals in research, education, and regional economic development. This paper describes the CASE Center and its interaction with industry, government, and universities.