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- Keyword
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- Acoustic analysis, Acoustic scattering, Acoustic signal processing, Acoustic resonance, Acoustic spectrum analyzers (1)
- Chirp modulation, time-frequency transform, Rayleigh fading, digital communications, underwater communications, underwater modem, underwater acoustical channel, acoustical communication (1)
- Dielectric surface, beam-splitters, polarization, refraction (1)
- Phase retarders, beam splitter, film, angle, design, ellipsometry, conventions, retardation, plates (1)
- Time-frequency transform, sediment classification, buried target classification (1)
Articles 1 - 8 of 8
Full-Text Articles in Engineering
Sub-Bottom Profiling Using Time-Frequency Analysis, William Sanders, Dale Bibee, Edit J. Kaminsky
Sub-Bottom Profiling Using Time-Frequency Analysis, William Sanders, Dale Bibee, Edit J. Kaminsky
Electrical Engineering Faculty Publications
No abstract provided.
Embedded Centrosymmetric Multilayer Stacks As Complete-Transmission Quarter-Wave And Half-Wave Retarders Under Conditions Of Frustrated Total Internal Reflection, S. R. Perla, R. M.A. Azzam
Embedded Centrosymmetric Multilayer Stacks As Complete-Transmission Quarter-Wave And Half-Wave Retarders Under Conditions Of Frustrated Total Internal Reflection, S. R. Perla, R. M.A. Azzam
Electrical Engineering Faculty Publications
A centrosymmetric multilayer stack of two transparent materials, which is embedded in a high-index prism, can function as a complete-transmission quarter-wave or half-wave retarder (QWR or HWR) under conditions of frustrated total internal reflection. The multilayer consists of a high-index center layer sandwiched between two identical low-index films with high-index–low-index bilayers repeated on both sides of the central trilayer, maintaining the symmetry of the entire stack and constituting a QWR ( Δt=90° or 270°) or HWR (Δt=180°) in transmission. A QWR design at wavelengthλ=1.55 μm is presented that employs an 11-layer stack of Si and SiO2 thin films, which is …
Wide-Angle, High-Extinction-Ratio, Infrared Polarizing Beam Splitters Using Frustrated Total Internal Reflection By An Embedded Centrosymmetric Multilayer, Siva R. Perla, R. M.A. Azzam
Wide-Angle, High-Extinction-Ratio, Infrared Polarizing Beam Splitters Using Frustrated Total Internal Reflection By An Embedded Centrosymmetric Multilayer, Siva R. Perla, R. M.A. Azzam
Electrical Engineering Faculty Publications
A centrosymmetric multilayer stack of two transparent thin-film materials, which is embedded in a high-index prism, is designed to function as an efficient polarizer or polarizing beam splitter (PBS) under conditions of frustrated total internal reflection over an extended range of incidence angles. The S(LH)kLHL(HL)kS multilayer structure consists of a high-index center layer H sandwiched between two identical low-index films L and high-index-low-index bilayers repeated (k times) on both sides of the central trilayer maintaining the symmetry of the entire stack. For a given set of refractive indices, all possible solutions for the thicknesses of …
Performance Of Chirp-Slope Keying With Joint Time-Frequency Detectors, Inigo X. Incer, Edit J. Kaminsky
Performance Of Chirp-Slope Keying With Joint Time-Frequency Detectors, Inigo X. Incer, Edit J. Kaminsky
Electrical Engineering Faculty Publications
This paper discusses recent studies on Chirp Slope Keying (CSK) as a scheme suitable for underwater communications and presents a new study on the performance of a time-frequency receiver in a Rayleigh fading environment. As expected, CSK proves to be a digital modulation scheme inferior in the AWGN channel as compared to traditional schemes but very promising in more detrimental channels present in underwater communications. In effect, while most schemes’ performances decay abruptly with the addition of new disturbances, a time-frequency CSK receiver’s performance deteriorates slowly with increasing Rayleigh fading. Intuition dictates that CSK will overpower other schemes as channel …
Time-Frequency Transform Techniques For Seabed And Buried Target Classification, Madalina Barbu, Edit J. Kaminsky, Russell E. Trahan
Time-Frequency Transform Techniques For Seabed And Buried Target Classification, Madalina Barbu, Edit J. Kaminsky, Russell E. Trahan
Electrical Engineering Faculty Publications
An approach for processing sonar signals with the ultimate goal of ocean bottom sediment classification and underwater buried target classification is presented in this paper. Work reported for sediment classification is based on sonar data collected by one of the AN/AQS-20’s sonars. Synthetic data, simulating data acquired by parametric sonar, is employed for target classification. The technique is based on the Fractional Fourier Transform (FrFT), which is better suited for sonar applications because FrFT uses linear chirps as basis functions. In the first stage of the algorithm, FrFT requires finding the optimum order of the transform that can be estimated …
Quarter-Wave Layers With 50% Reflectance For Obliquely Incident Unpolarized Light, R. M.A. Azzam, F. F. Sudradjat
Quarter-Wave Layers With 50% Reflectance For Obliquely Incident Unpolarized Light, R. M.A. Azzam, F. F. Sudradjat
Electrical Engineering Faculty Publications
The conditions under which light interference in a transparent quarter-wave layer of refractive index n1 on a transparent substrate of refractive index n2 leads to 50% reflectance for incident unpolarized light at an angle φ are determined. Two distinct solution branches are obtained that correspond to light reflection above and below the polarizing angle, φp , of zero reflection for p polarization. The real p and s amplitude reflection coefficients have the same (negative) sign for the solution branch φ>φp and have opposite signs for the solution branch φ<φp . Operation at φ<φp is the basis of a 50%–50% beam splitter that divides an incident totally polarized light beam (with p and s components of equal intensity) into reflected and …
Polarizing Properties Of Embedded Symmetric Trilayer Stacks Under Conditions Of Frustrated Total Internal Reflection, Rasheed M.A. Azzam, Siva R. Perla
Polarizing Properties Of Embedded Symmetric Trilayer Stacks Under Conditions Of Frustrated Total Internal Reflection, Rasheed M.A. Azzam, Siva R. Perla
Electrical Engineering Faculty Publications
An error in the application of the design procedure described in a previous paper [Appl. Opt. 45, 1650 (2006)] has been corrected, and new revised figures are included in this erratum.
Parallel-Slab Polarizing Beam Splitter And Photopolarimeter, R. M.A. Azzam
Parallel-Slab Polarizing Beam Splitter And Photopolarimeter, R. M.A. Azzam
Electrical Engineering Faculty Publications
A dielectric-slab polarizing beam splitter (PBS) is described that generates two parallel beams of orthogonal p and s linear polarizations in reflection and functions as a diattenuator in transmission. The plane-parallel slab, which is set at Brewster's angle, is uncoated on one side and has an s-polarization antireflection coating (s-ARC) on the other side. Analytical results are presented for a PBS that uses a high-index slab coated with a low-index single-layer s-ARC, which is particularly suited for the IR. A novel multistage photopolarimeter that uses two such PBSs in series is described as being capable of sequential and simultaneous measurement …