Analysis of Radiation by Linear Arrays of Parallel Horizontal Wire Antennas Over Imperfect Ground


Book Description

A user oriented computer program is presented and described for analyzing radiation from linear arrays of parallel horizontal thin-wire antennas over the surface of an imperfectly conducting earth. The program is equipped to treat unequally spaced arrays of wires that can be of different lengths and radii, but it is assumed the wires are all centerfed. The wires are assumed to be unloaded and that the conductivity of the earth is finite. The effects of the imperfectly conducting earth are accounted for approximately by using the method of reflection coefficients. Computed output consists of current distributions, input impedances, and far-field patterns specified by the user.




Analysis of Radiation by Wire Antennas Over Imperfect Ground


Book Description

Three user-oriented computer programs are presented and described for analyzing radiation from arrays of parallel vertical wires, parallel horizontal wires, and also arbitrary wire configurations over the surface of an imperfectly conducting earth. The first two programs are equipped to treat unequally spaced arrays of wires that can be of different lengths and radii and of arbitrary excitation and loading. The effects of the imperfectly conducting earth are accounted for in an essentailly exact manner by using the Sommerfeld formulation. The third program treats arbitrary wire antennas and incorporates the ground effects approximately by using the reflection-coefficient method. Computed output consists of current distribution, input impedances, and field patterns specified by the user.




Analysis of Arbitrarily Oriented Thin Wire Antenna Arrays Over Imperfect Ground Planes


Book Description

The work considers the analysis of antenna and arrays of thin wires of arbitrary orientation above imperfectly conducting ground planes. Emphasis is placed on the development of fast and accurate techniques for computation of the characteristics of antenna systems. An important problem is the evaluation of certain semi-infinite integrals encountered in the exact Sommerfeld solution. The time required for computation of these integrals is reduced by the application of interpolatory quadrature formulas. Where applicable, a modified method of steepest descent is used to evaluate the integrals. The approximate reflection coefficient method is derived from the Sommerfeld formulation via the method of steepest descent. The accuracy of the reflection coefficient method relative to the Sommerfeld method is discussed. Finally, formulas convenient for the optimization of various performance indices are discussed. Typical indices that have been optimized, both with and without constraints, are directivity, power gain, quality factor, and main beam radiation efficiency.




Programs for Analysis of Radiation by Linear Arrays of Vertical Wire Antennas Over Imperfect Ground


Book Description

Two user-oriented computer programs are presented and described for analyzing radiation from linear arrays of vertical thin-wire antennas over the horizontal plane surface of an imperfectly conducting earth. The first program can handle arbitrary excitation of the array wire, although it is assumed they are equally spaced and all of the same length and radius. The second program is equipped to treat unequally spaced arrays of wires that can be of different lengths and radii, but it is assumed the wires are all centerfed. Both assume the wires are unloaded and that the conductivity of the earth is finite. The effects of the imperfectly conducting earth are accounted for approximately by using the method of reflection coefficients. Computed output consists of current distributions, input impedances, and far-field patterns specified by the user. (Author).




Scientific and Technical Aerospace Reports


Book Description

Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.










Index to IEEE Publications


Book Description

Issues for 1973- cover the entire IEEE technical literature.