Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
-
- <p>Frequency discriminators<br />Radar targets<br />Tracking radar -- Computer programs<br />Tracking radar</p> (1)
- Antenna arrays -- Design<br />Antennas (Electronics)<br />Antenna radiation patterns<br />Electromagnetic fields -- Measurement (1)
- Diodes, Semiconductor<br />Junction transistors<br />Computer-aided design (1)
- Electric power systems -- Control<br />Electric power system stability -- Mathematical models (1)
- Integrated circuits -- Design<br />Frequency dividers<br />Modulation (Electronics) -- Mathematical models (1)
Articles 1 - 8 of 8
Full-Text Articles in Engineering
The Zeroth-Order Current Distribution In Arbitrary Arrays Of Thin-Linear Dipoles, Samuel Benton Roberts
The Zeroth-Order Current Distribution In Arbitrary Arrays Of Thin-Linear Dipoles, Samuel Benton Roberts
Doctoral Dissertations
The potentials at the terminals of the elements of an array of N thin-linear dipoles is calculated using zeroth-order currents. It is shown that if even currents are present on the elements, the terminal potentials cannot be balanced, and that if the terminal potentials are balanced, odd currents must exist on the elements. A simple method of calculating the complex ratio of odd to even currents on each element is given. The method is applied to several arrays, and the results for tangential circular arrays are compared to an accurate numerical solution. The approximate method has the accuracy of the …
Microwave Propagation Through Isotropic Inhomogeneous Photoconductive Media, Thomas Van Doren
Microwave Propagation Through Isotropic Inhomogeneous Photoconductive Media, Thomas Van Doren
Doctoral Dissertations
"The electromagnetic field equations for microwave propagation through a rectangular waveguide filled with a lossy, isotropic, linear, inhomogeneous material are derived in matrix form and solved numerically by computer. The theoretical effects of photo-induced conductivity and dielectric constant variations on microwave attenuation, phase shift, and voltage standing wave ratio are plotted for typical examples in the X-band frequency range. The theoretical calculations indicate that a two order-of-magnitude change in the conductivity can produce a 25 db change in the attenuation or a 100 degree change in the angle of the reflection coefficient. The theoretical predictions are verified qualitatively by experiments …
Analysis Of The Traveling-Wave Transistor, Vernon Ray Stanley
Analysis Of The Traveling-Wave Transistor, Vernon Ray Stanley
Doctoral Dissertations
"Transmission lines containing independent and dependent distributed sources are considered and the transfer matrices of various active distributed lines are derived. A method is discussed by which a lossy line can be made lossless by the appropriate choice of distributed sources. A steady-state analysis of the uniform traveling wave transistor is given. Considering the device as an active four port network, the transfer matrix is found in closed form and the power gain, output voltage, and input impedance are found. A computer program is written and the frequency response is given for various values of line parameters and terminations. Finally, …
Models For The Pn Diode And The Npn And Pnp Transistor For Use In Computer Aided Design And Analysis Programs, Glenn Ronald Case
Models For The Pn Diode And The Npn And Pnp Transistor For Use In Computer Aided Design And Analysis Programs, Glenn Ronald Case
Doctoral Dissertations
"This work is concerned with the problem of developing suitable mathematical representations for the pn junction diode and npn and pnp transistors for use in computer aided design and analysis programs. The Ebers-Moll model as used in the Net-1 program has been considerably improved, particularly regarding base resistance prediction, prediction of high forward current behavior, and the addition of reverse breakdown terms. The resulting models show substantial improvement in representation of d-c and transient characteristics. Some improvement in a-c characteristics has also been obtained. Methods of obtaining parameters for the new model and several of the present models, given measured …
Signal Distortion In A Regenerative Frequency Divider, Carl Ray Ryan
Signal Distortion In A Regenerative Frequency Divider, Carl Ray Ryan
Doctoral Dissertations
"A regenerative frequency divider can be constructed with one integrated circuit and a single-pole tuned circuit. The divider can be used as a means for reducing the modulation index of either deterministic or random signals. This reduction in modulation index can simplify many signal processing schemes. This technique can be used up to S-band frequencies. The mathematical model of the regenerative frequency divider corresponds very closely to that of a first order Phase Locked Loop (PLL). The loop gain is determined in part by the nonlinear element used in the feedback loop. The loop gain is also proportional to the …
Improvement In Target Detection With A Frequency Agile Pulsed Non-Coherent Radar, Kenneth Lee Horn
Improvement In Target Detection With A Frequency Agile Pulsed Non-Coherent Radar, Kenneth Lee Horn
Doctoral Dissertations
"Frequency agile tracking radars have received considerable attention in the literature. Frequency agility is useful in reducing target scintillations, thereby reducing tracking errors under certain conditions. However, little attention has been devoted to the improvement that can be expected in target detection with a frequency agile radar. In the past, complete pulse-to-pulse decorrelation of the target returns has been assumed for all of the analyses concerning target detection with frequency agile radars. This assumption always implies a transmitter with a large bandwidth.
This dissertation analyses a pulsed non-coherent frequency agile radar applied to Swerling's Case I target. The target model …
A Method For Determining Transient Stability In Power Systems, Charles A. Gross
A Method For Determining Transient Stability In Power Systems, Charles A. Gross
Doctoral Dissertations
"Given a three phase ac power system consisting of synchronous alternators interconnected by transmission lines and other items of electrical transmission equipment, a method is presented which determines the stability of the system when subjected to a three phase symmetrical fault, and to the subsequent clearing of the fault. It is inherent in the method that an estimation of system stability, assuming an instantaneous clearing of the fault, is available. The critical clearing time is therefore determined. The effect of a speed control loop on the system's largest machine is investigated. The method is applied to two, three, four, and …
Spherical Antenna Array, Narong Yoothanom
Spherical Antenna Array, Narong Yoothanom
Doctoral Dissertations
"The far field radiation pattern of an isotropic spherical antenna array with two types of element distributions, a latitude-longitude distribution and an approximately equally-spaced distribution, has been analyzed using Poisson's Sum Formula. Beamwidth expressions of both element distributions are found in various planes. All numerical results are given only for the case of 21 rings"--Abstract, page ii.