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Electrical and Computer Engineering Commons

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Full-Text Articles in Electrical and Computer Engineering

P300-Based Speller Brain-Computer Interface, Reza Fazel-Rezai Oct 2009

P300-Based Speller Brain-Computer Interface, Reza Fazel-Rezai

Electrical Engineering Faculty Publications

No abstract provided.


Broadband Ir Polarizing Beam Splitter Using A Subwavelength-Structured One-Dimensional Photonic-Crystal Layer Embedded In A High-Index Prism, R. M.A. Azzam, H. K. Khanfar Sep 2009

Broadband Ir Polarizing Beam Splitter Using A Subwavelength-Structured One-Dimensional Photonic-Crystal Layer Embedded In A High-Index Prism, R. M.A. Azzam, H. K. Khanfar

Electrical Engineering Faculty Publications

An iterative procedure for the design of a polarizing beam splitter (PBS) that uses a form-birefringent, subwavelength-structured, one-dimensional photonic-crystal layer (SWS 1-D PCL) embedded in a high-index cubical prism is presented. The PBS is based on index matching and total transmission for the p polarization and total internal reflection for the s polarization at the prism-PCL interface at 45 degrees angle of incidence. A high extinction ratio in reflection (>50 dB) over the 4-12 mu m IR spectral range is achieved using a SWS 1-D PCL of ZnTe embedded in a ZnS cube within an external field of view …


Tilted Parallel Dielectric Slab As A Multilevel Attenuator For Incident P- Or S-Polarized Light, R. M.A. Azzam Jan 2009

Tilted Parallel Dielectric Slab As A Multilevel Attenuator For Incident P- Or S-Polarized Light, R. M.A. Azzam

Electrical Engineering Faculty Publications

Under the condition of first-order blooming, a parallel dielectric slab, which is inserted in the path of an obliquely incident p- or s-polarized light beam, introduces multiple discrete attenuation levels given by 1/3, 4/27, 4/243,...... in reflection and 4/9, 4/81, 4/729,...... in transmission. These attenuation levels are independent of the slab refractive index, incident p or s linear polarization, or the presence of identical transparent surface coatings at the front and back sides of the slab. Therefore, the tilted slab provides multidecade reflectance and attenuation reference values that can be used in calibrating spectrophotometers and filters, and also …


Signal Classification In Fading Channels Using Cyclic Spectral Analysis, Eric Like, Vasu D. Chakravarthy, Paul Ratazzi, Zhiqiang Wu Jan 2009

Signal Classification In Fading Channels Using Cyclic Spectral Analysis, Eric Like, Vasu D. Chakravarthy, Paul Ratazzi, Zhiqiang Wu

Electrical Engineering Faculty Publications

Cognitive Radio (CR), a hierarchical Dynamic Spectrum Access (DSA) model, has been considered as a strong candidate for future communication systems improving spectrum efficiency utilizing unused spectrum of opportunity. However, to ensure the effectiveness of dynamic spectrum access, accurate signal classification in fading channels at low signal to noise ratio is essential. In this paper, a hierarchical cyclostationary-based classifier is proposed to reliably identify the signal type of a wide range of unknown signals. The proposed system assumes no a priori knowledge of critical signal statistics such as carrier frequency, carrier phase, or symbol rate. The system is designed with …


A Trellis-Coded Modulation Scheme With A Novel Expanded 16-Dimensional Constant Envelope Q2psk Constellation, Milton I. Quinteros, Edit J. Kaminsky, Kenneth V. Cartwright Jan 2009

A Trellis-Coded Modulation Scheme With A Novel Expanded 16-Dimensional Constant Envelope Q2psk Constellation, Milton I. Quinteros, Edit J. Kaminsky, Kenneth V. Cartwright

Electrical Engineering Faculty Publications

This paper presents a TCM scheme that uses a new expanded 16-Dimensional Constant Envelope Q2PSK constellation along with a simple convolutional encoder of rate 2/3. An effective gain of 2.67 dB over uncoded CEQ2PSK is achievable with low complexity, and without suffering from constellation expansion penalty. Larger coding gains are easily achieved with encoders of higher rates. In addition, an optimal hardware implementation of the required decoders is described.