Engineering Commons^™

Optimal Linear Coding For A Multichannel System, Kyong-Hwa Lee

Electrical and Computer Engineering ETDs

This paper is concerned with the problem of obtaining the optimal linear vector coding (transformation) method that matches an r-dimensional vector signal and a k-dimensional channel under a given channel power constraint. the encoder converts the r correlated random variables into r independent random variables and selects at most k independent random variables which correspond to the k largest eigenvalues of the signal covarience matrix Q. The encoder reinserts cross-correlation into the k random variables in such a way that the largest eigenvalue of Q is assigned to the smallest eigenvalue of the channel noise covarience matrix R and the …

An Investigation Of The Optical Absorption Properties Of Silicon As Related To Its Electrical Conductivity, Onofrio Louis Russo

Dissertations

The purpose of this study is to demonstrate the feasibility of obtaining the electrical conductivity of band gap semiconductors, by considering the absorption of radiation in the visible region. The experimental evidence confirmed predictions that the conductivities of the silicon samples are related to the horizontal displacement of energy in the absorption curves. The material used in this study was p-doped silicon, although the approach should be valid in general for either elemental or compound semiconductors.

The absorption coefficient for silicon was measured in the radiation region between 2.0 and 3.0 ev. This region above the indirect band gap (= …

Optimal Control And Identification Of Stochastic Systems Using Differential Game Theory, Harry Marvin Burbank

Dissertations

This dissertation deals with linear systems subjected to stochastic disturbances. The class of stochastic processes considered is the class of second order stochastic processes characterized by having finite continuous covariance. The properties of the covariance provide means to formulate optimization problems without the difficulties present when the covariance is not finite or continuous.

The first aspect studied was several classes of optimal control problems. The effects of the stochastic processes were approximated by the effects of its first two moments. This procedure resulted in allowing optimal system controls to be found whatever the first two moments of the stochastic input …

Design Of A Yig-Tuned Oscillator, Tien Liang Jin

Theses

A technique for designing YIG (yttrium-iron garnet) tuned transistor oscillators, tunable over the range of frequencies from 500 to 950 MHZ, is presented. The approach taken differs appreciably from that used in the design of conventional LC-tuned oscillators. One major difference is that the YIG tuning mechanism is electrically controlled. The YIG tuning element is treated as a single unit and is not resolved into an equivalent LC circuit. Instead, a direct method using reflection coefficients measured at network terminals to characterize various design stages is applied. The transistor is also characterized by reflection and transmission coefficients, i.e., S-parameters. Thus …

Design, Fabrication, And Application Of Uniformly Distributed Rc Networks For Use In Electronic Circuits, Michael Flynn Kavanaugh

Doctoral Dissertations

"In the design of electronic circuits, both linear and non-linear, one of the goals is the reduction of the number of elements needed to complete the design. By using distributed RC networks a reduction in the number of elements by at least 50% is usually possible. This dissertation discusses several distributed RC networks, develops detailed design procedures for each, and applies them in the design of electronic circuits.

The indefinite admittance matrix (IAM) for the DRURC (double-resistive uniformly distributed RC network) and the URC (single-resistive uniformly distributed RC network) , which have been previously derived, are used as the starting …

Excitation Of Source Electromagnetic Waves At Microwave Frequencies Using Optical Techniques, M. Davarpanah

Doctoral Dissertations

"The coupling efficiencies for the excitation of surface electromagnetic waves (SEW} for both the prism and the grating techniques have been studied experimentally in the microwave frequency range. The grating experiments included studies of the SEW coupling efficiencies as functions of the frequency, the angle of incidence, the grating constant, the number of grating bars, and the position of the grating bar at which the maximum radiation field of the antenna was aimed. For the prism coupling technique, the coupling efficiency was studied as functions of the angle of incidence, the aiming point of the transmitting antenna on the prism …