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- Electromagnetic-waves (1)
- Fractional Fourier transform, impulse response, seabed classification, time-frequency distributions, volume search sonar (1)
- Q2PSK, CEQ2PSK, bandlimited channel, spectral efficiency, multidimensional TCM, constant envelope (1)
- Reflection, interface, coatings (1)
- Synchronization, blind phase estimation, quadrature amplitude modulation, blind carrier phase recovery (1)
Articles 1 - 8 of 8
Full-Text Articles in Engineering
Infrared Broadband 50%-50% Beam Splitters For S-Polarized Light, R. M.A. Azzam
Infrared Broadband 50%-50% Beam Splitters For S-Polarized Light, R. M.A. Azzam
Electrical Engineering Faculty Publications
Prisms and slabs made of high-refractive-index materials such as ZnSe, Ge, and Si can be designed as broadband, 50%-50%, beam splitters (BSs) for obliquely incident s- polarized light in the near- and mid-IR. The beam-splitting face of the prism or slab is uncoated, while the exit face is antireflection coated. The split beams travel in orthogonal directions when light is incident at the Brewster angle. A novel design is also described that uses Brewster-angle reflection at the SiO2-Si interface to achieve a 50%-50%s-polarization BS over the 1.2-3.5 μm spectral range. Such s-polarization BSs are particularly suited for interferometry …
Phase Shifts In Frustrated Total Internal Reflection And Optical Tunneling By An Embedded Low-Index Thin Film, R. M.A. Azzam
Phase Shifts In Frustrated Total Internal Reflection And Optical Tunneling By An Embedded Low-Index Thin Film, R. M.A. Azzam
Electrical Engineering Faculty Publications
Simple and explicit expressions for the phase shifts that p- and s-polarized light experience in frustrated total internal reflection (FTIR) and optical tunneling by an embedded low-index thin film are obtained. The differential phase shifts in reflection and transmission Δr,Δt are found to be identical, and the associated ellipsometric parameters ψr,ψt are governed by a simple relation, independent of film thickness. When the Fresnel interface reflection phase shifts for the pand s polarizations or their average are quarter-wave, the corresponding overall reflection phase shifts introduced by the embedded layer are also quarter-wave for all values of film …
Acoustic Seabed Classification Using Fractional Fourier Transform, Madalina Barbu, Edit J. Kaminsky, Russell E. Trahan
Acoustic Seabed Classification Using Fractional Fourier Transform, Madalina Barbu, Edit J. Kaminsky, Russell E. Trahan
Electrical Engineering Faculty Publications
In this paper we present a time-frequency approach for acoustic seabed classification. Work reported is based on sonar data collected by the Volume Search Sonar (VSS), one of the five sonar systems in the AN/AQS-20. The Volume Search Sonar is a beamformed multibeam sonar system with 27 fore and 27 aft beams, covering almost the entire water volume (from above horizontal, through vertical, back to above horizontal). The processing of a data set of measurement in shallow water is performed using the Fractional Fourier Transform algorithm in order to determine the impulse response of the sediment. The Fractional Fourier transform …
Fuzzy-Neural Cost Estimation For Engine Tests, Edit J. Kaminsky, Holly Danker-Mcdermott, Freddie Douglas
Fuzzy-Neural Cost Estimation For Engine Tests, Edit J. Kaminsky, Holly Danker-Mcdermott, Freddie Douglas
Electrical Engineering Faculty Publications
This chapter discusses artificial computational intelligence methods as applied to cost prediction. We present the development of a suite of hybrid fuzzy-neural systems for predicting the cost of performing engine tests at NASA’s Stennis Space Center testing facilities. The system is composed of several adaptive network-based fuzzy inference systems (ANFIS), with or without neural subsystems. The output produced by each system in the suite is a rough order of magnitude (ROM) cost estimate for performing the engine test. Basic systems predict cost based solely on raw test data, whereas others use preprocessing of these data, such as principal components and …
Performance And Spectral Analysis Of Q2psk And Ce Q2psk Systems In Ideal Bandlimited Channels, Milton I. Quinteros, Edit J. Kaminsky, Kenneth V. Cartwright
Performance And Spectral Analysis Of Q2psk And Ce Q2psk Systems In Ideal Bandlimited Channels, Milton I. Quinteros, Edit J. Kaminsky, Kenneth V. Cartwright
Electrical Engineering Faculty Publications
The authors present theoretical performance analysis and simulation results for Quadrature-Quadrature Phase Shift Keying (Q2PSK), Constant Envelope (CE) Q2PSK, and trelliscoded 16D CEQ2PSK in ideal bandlimited channels of various bandwidths. The performance of receivers with and without channel estimation is reported. Spectral analysis is presented for each system, in addition to MSK and expanded uncoded 16D CEQ2PSK. We show that the effects of bandlimiting are most severe for Q2PSK. Knowledge of the channel information aids 4D CEQ2PSK the least. Only 6.8 dB of SNR is needed for the TCM system for a bit error rate of 10−5 for the narrowest …
Chirp Signaling Offers Modulation Scheme For Underwater Communications, Edit J. Kaminsky
Chirp Signaling Offers Modulation Scheme For Underwater Communications, Edit J. Kaminsky
Electrical Engineering Faculty Publications
Information contained in the slope of chirp signals can be employed for digital underwater acoustic communications across a broad range of applications.
Time-Frequency Methods For Detection And Classification Of Long Buried Targets, Edit J. Kaminsky, Madalina Barbu, Dale Bibee
Time-Frequency Methods For Detection And Classification Of Long Buried Targets, Edit J. Kaminsky, Madalina Barbu, Dale Bibee
Electrical Engineering Faculty Publications
No abstract provided.
A Simple Improvement To The Viterbi And Viterbi Monomial-Based Phase Estimators, Kenneth V. Cartwright, Edit J. Kaminsky
A Simple Improvement To The Viterbi And Viterbi Monomial-Based Phase Estimators, Kenneth V. Cartwright, Edit J. Kaminsky
Electrical Engineering Faculty Publications
It is well known that the Viterbi and Viterbi Monomial- Based Phase Estimator, which includes the Mth Power Estimator, performs poorly for cross QAM signals. However, it is shown here that by allowing the power of the monomial to be negative, much improved performance can be realized at medium to high signalto- noise ratios (SNR). Monte Carlo simulations are used to demonstrate the efficacy of this novel simple extension, for 32- and 128-QAM systems. In principle, this extension can also be applied to other constellations, e.g., (4,12)-PSK.