A method for the matching of a complex load impedance to the characteristic impedance of a transmission line is presented. The lengths of two transformer sections which have preselected characteristic impedances are d...
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There seems to be a popular superstition among engineers that the voltage and current relations at different points in a transmission line are peculiar and are not governed by Ohms law. This idea is not true. A transm...
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An analytical program for calculating the field distribution about a microstrip transmission line bounded by a shielding wall is used to calculate the impedance, velocity, and attenuation parameters. The program input...
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An analytical program for calculating the field distribution about a microstrip transmission line bounded by a shielding wall is used to calculate the impedance, velocity, and attenuation parameters. The program input parameters are the dimensions of the strip and shielding wall and the relative dielectric constant of the substrate material. The field distribution about the strip is integrated to find the charge density on the strip and walls with and without the dielectric substrate. From these two calculations, the relative velocity and impedance can be calculated.
Some results are given in the formal theory of nonuniform transmission lines whose constitutive parameters are bounded measurable functions of the geometric abscissa x and holomorphic functions of the complex variable...
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Review of the Subject—Several independent studies have been made recently to determine the economies of a large, uniform power system. The two studies of more general interest were those conducted by the Department o...
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Review of the Subject—Several independent studies have been made recently to determine the economies of a large, uniform power system. The two studies of more general interest were those conducted by the Department of the Interior, under the direction of W. S. Murray, for the Superpower Zone, and by F. G. Baum for the United States. Both of these investigations are available in published form. During the progress of the Superpower Survey, one of the longest transmission lines proposed was that extending 350 miles from the Niagara Falls Development to New York City. Under emergency conditions on this line, the power limit for the maximum amount of power was approached by two twin-circuit tower lines with three circuits carrying the emergency load. The maximum power limit would have been exceeded if two single-circuit tower lines had been employed, even though the transmission voltages and the total copper cross-section were the same as with the two twin-circuit tower lines. Similarly, several long, high-voltage lines will be required in a nation-wide system, especially through the middle western region as shown by Mr. Baum's report. The tendency to extensive transmission systems has emphasized the necessity of considering the factors which will limit the amount of power that can be transmitted any distance with the highest practical transmission voltage. On account of the transmission line characteristics, the power limits will be greater when the system is regulated by synchronous apparatus than when no such apparatus is used so that two power limits will be considered in this paper;first, for an unregulated system;and second, for a regulated system. However, while we are primarily interested in high-voltage systems in this paper, it should be kept in mind that these same methods of calculation may be applied to lower voltages in determining the power limitations of station tie lines. It is commonly accepted that different types of networks have certain power limita
Five different types of transmission line systems are analyzed and are shown to possess directional properties at the lower radio frequencies. The conditions of mismatch on either transmission line or on both transmis...
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Five different types of transmission line systems are analyzed and are shown to possess directional properties at the lower radio frequencies. The conditions of mismatch on either transmission line or on both transmission lines have been taken into account, as well as lengths of coupling greater than a fractional wavelength. A new and more general scatter matrix for directional couplers which includes the condition of mismatch is developed. In addition, lumped circuit directional couplers have been developed as a consequence of the general transmission line theory.
An iterative circuit, diode, transmission phase shifter is discussed, having a canonic form that consists, of a length of transmission line symmetrically loaded at its ends by small susceptances whose values are diode...
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An iterative circuit, diode, transmission phase shifter is discussed, having a canonic form that consists, of a length of transmission line symmetrically loaded at its ends by small susceptances whose values are diode controllable. The spacing of the susceptances is chosen so that their reflections are nearly mutually canceling, (about a quarter wavelength if equal magnitude, opposite sign susceptances are used). A change of electrical length of the section of 23/spl deg/, in principle, is obtainable with a maximum input VSWR of 1.04. Eight section, experimental circuits yielded 180/spl deg/ total phase shift with less than one decibel of loss in the L and S bands and peak RF power capability to 15 kilowatts. Operation to 140 kilowatts peak power was achieved with reduced phase shift per section. The transmission phase shifter is believed to be well suited as a phase control element for beam steering of array antennas.
A new method of constructing laser holograms is discussed wherein the only light used is that received directly from the object. Reconstruction is accomplished in the usual way. Long-distance holography is an immediat...
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A new method of constructing laser holograms is discussed wherein the only light used is that received directly from the object. Reconstruction is accomplished in the usual way. Long-distance holography is an immediate application.
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