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Full-Text Articles in Computer Engineering
System And Method For Performing Optical Code Division Multiple Access Communication Using Bpolar Codes, James F. Young, Benhaam Aazhnag, Lim Nguyen
System And Method For Performing Optical Code Division Multiple Access Communication Using Bpolar Codes, James F. Young, Benhaam Aazhnag, Lim Nguyen
Department of Electrical and Computer Engineering: Faculty Publications
An optical encoding and decoding system which performs code-division multiple access (CDMA) communication in the incoherent, or direct detection, optical domain using bipolar +1/-1 codes. The present invention uses code modu lation and detection principles that permit all-optical imple mentation of the bipolar. +1/-1. code and correlation detec tion that have been developed for the radio frequency (RF) systems. This is possible in spite of the non-negative, or unipolar, +1/0, nature of the incoherent optical system that only detects and processes the signal intensity. The unipolar optical system of the present invention is equivalent to the bipolar RF system in …
Design, Performance, And Applications Of A Coherent Ultra-Wideband Random Noise Radar, Ram M. Narayanan, Yi Xu, Paul D. Hoffmeyer, John O. Curtis
Design, Performance, And Applications Of A Coherent Ultra-Wideband Random Noise Radar, Ram M. Narayanan, Yi Xu, Paul D. Hoffmeyer, John O. Curtis
Department of Electrical and Computer Engineering: Faculty Publications
A novel coherent ultra-wideband radar system operating in the 1- to 2-GHz frequency range has been developed recently at the University of Nebraska. The radar system transmits white Gaussian noise. Detection and localization of buried objects is accomplished by correlating the reflected waveform with a time-delayed replica of the transmitted waveform. Broadband dual-polarized log-periodic antennas are used for transmission and reception. A unique signal-processing scheme is used to inject coherence into the system by frequency translation of the ultrawideband signal by a coherent 160-MHz phase-locked source prior to performing heterodyne correlation. The system coherence allows the extraction of a target’s …
Electromagneticbeamdirecting Means-Sampleanalyss System Stage, And Method Of Use, Daniel W. Thompson, Darin W. Glenn, John A. Woollam
Electromagneticbeamdirecting Means-Sampleanalyss System Stage, And Method Of Use, Daniel W. Thompson, Darin W. Glenn, John A. Woollam
Department of Electrical and Computer Engineering: Faculty Publications
Disclosed is an electromagnetic beam directing means for use with sample analysis systems, such as reflectometers, ellipsometers and polarimeters and the like, use of which facilitates investigation of sample systems which are not mounted to a sample analysis system sample system supporting stage. The present invention eliminates the requirement of extensive sample analysis system component realignment when alternatingly performing analysis of sample systems mounted upon, and mounted other than upon, a sample analysis system sample system supporting stage.
Apparatus And Method For Detection And Concentration Measurement Of Trace Metals Using Laser Induced Breakdown Spectroscopy, Dennis R. Alexander
Apparatus And Method For Detection And Concentration Measurement Of Trace Metals Using Laser Induced Breakdown Spectroscopy, Dennis R. Alexander
Department of Electrical and Computer Engineering: Faculty Publications
A method and apparatus for in situ detection and concentration measurement of trace elements in an analysis Sample is disclosed. The invention uses laser induced breakdown spectroscopy (LIBS) wherein femtosecond pulsed laser energy is employed to produce the plasma. The femtosecond pulsed laser energy is focused on the analysis Sample to produce the plasma and the resulting emission is delivered for spectral analysis. Because the method and apparatus of the present invention allow breakdown of the analysis Sample without propagation of energy to the Sample-air interface, a plasma is produced that consists essentially of Sample materials without being contaminated by …
Infrared Ellpsometer/ Polarmeter System, Method Of Calibration, And Use Thereof, Daniel W. Thompson, Blaine D. Johs
Infrared Ellpsometer/ Polarmeter System, Method Of Calibration, And Use Thereof, Daniel W. Thompson, Blaine D. Johs
Department of Electrical and Computer Engineering: Faculty Publications
A sample system investigation system, such as an ellipsometer or polarimeter system, for use in investigating sample systems with electromagnetic wavelengths in the infrared range, and a calibration method for compensating nonidealities in multi-dimensional system rotated and non-rotated component representing matricies, are disclosed. An essentially achromatic compensator of dual-rhomb construction, which introduces a (3*LAMBDA/4) phase shift, but essentially no deviation in the direction of propagation of a polarized beam of electromagnetic wavelengths caused to pass there through, even when said compensator is caused to continuously rotate, is also disclosed.
A New Radiosonde System For Profiling The Lower Troposphere, Brian R Corner, Robert D. Palmer
A New Radiosonde System For Profiling The Lower Troposphere, Brian R Corner, Robert D. Palmer
Department of Electrical and Computer Engineering: Faculty Publications
A new, inexpensive radiosonde transmitter and receiver system has been developed for measuring wind field inhomogeneities in the planetary boundary layer using multiple simultaneously launched balloons. The radio- sondes use a narrowband-frequency-modulated carrier signal to transmit atmospheric pressure and temperature information to a surface receiver. The pressure and temperature data transmitted by the radiosondes allow their height above the surface to be ascertained. In addition, the radiosondes can be tracked with a photographic camera system to provide the azimuth and elevation angles of the radiosondes during their ascent, so that their three-dimensional horizontal position can be determined. By tracking the …
Electromagnetic Beam Directing Means-Sample Analysis System Stage, And Method Of Use, Daniel W. Thomspon, Darin W. Glenn, John A. Woollam
Electromagnetic Beam Directing Means-Sample Analysis System Stage, And Method Of Use, Daniel W. Thomspon, Darin W. Glenn, John A. Woollam
Department of Electrical and Computer Engineering: Faculty Publications
Disclosed is an electromagnetic beam directing means for use with sample analysis systems, such as relfectometers, ellipsometers and polarimeters and the like, use of which facilitates investigation of sample systems which are not mounted to a sample analysis system sample system supporting stage. The present invention eliminates the requirement os extensice sample analysis system component realignment when alternatingly performing analysis of sample systems mounted upon, and mounted other than upon, a sample analysis system sample system supporting stage.