Open Access. Powered by Scholars. Published by Universities.®
Electrical and Computer Engineering
Electrical and Computer Engineering Faculty Publications and Presentations
- Keyword
-
- Cathodes (2)
- Current density (2)
- Analog-digitial (A/D) conversion (1)
- Anodes (1)
- Automatic identification (1)
-
- Bilevel image denoising (1)
- CMOS photonics (1)
- Cavitation (1)
- Cavity magnetrons (1)
- Chalcogenide glass (1)
- Channel estimation (1)
- Charge injection (1)
- Circuit topology (1)
- Compact model (1)
- Continuous-time (CT) (1)
- Delta-sigma (ΔΣ) (1)
- Dictionary learning (1)
- Directional denoising (1)
- Excess loop delay (ELD) (1)
- Feedforward (1)
- Field emission arrays (1)
- Film and device characterization (1)
- Frogs (1)
- Image degradation model (1)
- Joints (1)
- Low-current (1)
- MZM (1)
- Machine learning (1)
- Magnetic fields (1)
- Materials Science (1)
Articles 1 - 14 of 14
Full-Text Articles in Engineering
Simulation Of A Rising Sun Magnetron Employing A Faceted Cathode With A Continuous Current Source, Sulmer Fernandez-Gutierrez, Jim Browning, Ming-Chieh Lin, David N. Smithe, Jack Watrous
Simulation Of A Rising Sun Magnetron Employing A Faceted Cathode With A Continuous Current Source, Sulmer Fernandez-Gutierrez, Jim Browning, Ming-Chieh Lin, David N. Smithe, Jack Watrous
Electrical and Computer Engineering Faculty Publications and Presentations
It has been proposed that gated field emitters could be used in place of conventional thermionic cathodes to control the current injection in a magnetron, both temporally and spatially. Since gated field emitters have to be fabricated on flat surfaces, a faceted cathode would be used to implement this approach. A 2D ten cavity, rising sun magnetron has been modeled using the particle-in-cell code VORPAL. Cylindrical, five-sided, and ten-sided faceted cathodes were modeled to study the variation of magnetron operation due to the cathode shape. This work shows the results of the device performance employing three different cathode geometries with …
Noise-Enhanced Information Systems, Hao Chen, Lav R. Varshney, Pramod K. Varshney
Noise-Enhanced Information Systems, Hao Chen, Lav R. Varshney, Pramod K. Varshney
Electrical and Computer Engineering Faculty Publications and Presentations
Noise, traditionally defined as an unwanted signal or disturbance, has been shown to play an important constructive role in many information processing systems and algorithms. This noise enhancement has been observed and employed in many physical, biological, and engineered systems. Indeed stochastic facilitation (SF) has been found critical for certain biological information functions such as detection of weak, subthreshold stimuli or suprathreshold signals through both experimental verification and analytical model simulations. In this paper, we present a systematic noise-enhanced information processing framework to analyze and optimize the performance of engineered systems. System performance is evaluated not only in terms of …
Compact Verilog-A Modeling Of Silicon Traveling-Wave Modulator For Hybrid Cmos Photonic Circuit Design, Kehan Zhu, Vishal Saxena, Wan Kuang
Compact Verilog-A Modeling Of Silicon Traveling-Wave Modulator For Hybrid Cmos Photonic Circuit Design, Kehan Zhu, Vishal Saxena, Wan Kuang
Electrical and Computer Engineering Faculty Publications and Presentations
A compact Verilog-A model of silicon-based junction traveling-wave Mach-Zehnder modulator (MZM) is developed for hybrid CMOS and photonic system-level simulation in Cadence environment. Critical device functions such as the voltage dependent change of refractive index, small-signal RLGC parameters for the MZM arms are extracted from the photonic device characterization from OpSIS foundry. Thermo-optical coefficient is also considered in the model. Simulation results including electro-optic S21 is characterized for the phase modulator's bandwidth. Also, transient MZM operation with non-return to zero (NRZ) data transmission at 10 Gb/s and 20 Gb/s rates are demonstrated.
Sparsity-Based Edge Noise Removal From Bilevel Graphical Document Images, Thai V. Hoang, Elisa H. Barney Smith, Salvatore Tabbone
Sparsity-Based Edge Noise Removal From Bilevel Graphical Document Images, Thai V. Hoang, Elisa H. Barney Smith, Salvatore Tabbone
Electrical and Computer Engineering Faculty Publications and Presentations
This paper presents a new method to remove edge noise from graphical document images using geometrical regularities of the graphics contours that exist in the images. Denoising is understood as a recovery problem and is accomplished by employing a sparse representation framework in the form of a basis pursuit denoising algorithm. Directional information of the graphics contours is encoded by atoms in an overcomplete dictionary which is designed to match the input data. The optimal precision parameter used in this framework is shown to have a linear relationship with the level of the noise that exists in the image. Experimental …
Phase Control And Fast Start-Up Of A Magnetron Using Modulation Of An Addressable Faceted Cathode, J. Browning, S. Fernandez-Gutierrez, M. C. Lin, D. N. Smithe, J. Watrous
Phase Control And Fast Start-Up Of A Magnetron Using Modulation Of An Addressable Faceted Cathode, J. Browning, S. Fernandez-Gutierrez, M. C. Lin, D. N. Smithe, J. Watrous
Electrical and Computer Engineering Faculty Publications and Presentations
The use of an addressable, faceted cathode has been proposed as a method of modulating current injection in a magnetron to improve performance and control phase. To implement the controllable electron emission, five-sided and ten-sided faceted planar cathodes employing gated field emitters are considered as these emitters could be fabricated on flat substrates. For demonstration, the conformal finite-difference time-domain particle-in-cell simulation, as implemented in VORPAL, has been used to model a ten-cavity, rising sun magnetron using the modulated current sources and benchmarked against a typical continuous current source. For the modulated, ten-sided faceted cathode case, the electrons are injected from …
Energy-Efficient Stdp-Based Learning Circuits With Memristor Synapses, Xinyu Wu, Vishal Saxena, Kristy A. Campbell
Energy-Efficient Stdp-Based Learning Circuits With Memristor Synapses, Xinyu Wu, Vishal Saxena, Kristy A. Campbell
Electrical and Computer Engineering Faculty Publications and Presentations
It is now accepted that the traditional von Neumann architecture, with processor and memory separation, is ill suited to process parallel data streams which a mammalian brain can efficiently handle. Moreover, researchers now envision computing architectures which enable cognitive processing of massive amounts of data by identifying spatio-temporal relationships in real-time and solving complex pattern recognition problems. Memristor cross-point arrays, integrated with standard CMOS technology, are expected to result in massively parallel and low-power Neuromorphic computing architectures. Recently, significant progress has been made in spiking neural networks (SNN) which emulate data processing in the cortical brain. These architectures comprise of …
Low-Current Sensing Circuit And Topology For Portable Gamma Radiation Sensor, M. S. Ailavajhala, M. R. Latif, M. Mitkova
Low-Current Sensing Circuit And Topology For Portable Gamma Radiation Sensor, M. S. Ailavajhala, M. R. Latif, M. Mitkova
Electrical and Computer Engineering Faculty Publications and Presentations
A sensing circuit is presented for a portable/handheld semiconductor based radiation sensor, which senses low current changes without the inclusion of transistor noise issues. This circuit design block was implemented using supporting circuit architectures to enable sensing between 33pA to 1nA using low voltages. Additionally, a unique circuit topology is presented by which the effect of radiation damage to the silicon substrate and any devices on the substrate is reduced.
Ion Beam Effect On Ge-Se Chalcogenide Glass Films: Non-Volatile Memory Array Formation, Structural Changes And Device Performance, M. R. Latif, T. L. Nichol, M. Mitkova, D. A. Tenne, I. Csarnovics, S. Kokenyesi, A. Csik
Ion Beam Effect On Ge-Se Chalcogenide Glass Films: Non-Volatile Memory Array Formation, Structural Changes And Device Performance, M. R. Latif, T. L. Nichol, M. Mitkova, D. A. Tenne, I. Csarnovics, S. Kokenyesi, A. Csik
Electrical and Computer Engineering Faculty Publications and Presentations
In this work a scheme for fabricating a conductive bridge non-volatile memory arrays, using ion bombardment through a mask, is demonstrated. Blanket films and devices have been created to study the structural changes, surface roughness and device performance. Ar+ ions interaction on thin films of GexSe1−x system have been studied using Raman Spectroscopy, Atomic Force Microscopy (AFM) and Energy Dispersive X-Ray Spectroscopy (EDS). The performance of the memory devices has been analyzed based on the formation of vias and damage accumulation due to Ar+ ion interactions with GexSe1−x(x=0.25, 0.3 and 0.4) …
A Reference System For Animal Biometrics: Application To The Northern Leopard Frog, D. Petrovska-Delacrétaz, A. Edwards, J. Chiasson, G. Chollet, D. Pilliod
A Reference System For Animal Biometrics: Application To The Northern Leopard Frog, D. Petrovska-Delacrétaz, A. Edwards, J. Chiasson, G. Chollet, D. Pilliod
Electrical and Computer Engineering Faculty Publications and Presentations
Reference systems and public databases are available for human biometrics, but to our knowledge nothing is available for animal biometrics. This is surprising because animals are not required to give their agreement to be in a database. This paper proposes a reference system and database for the northern leopard frog (Lithobates pipiens). Both are available for reproducible experiments. Results of both open set and closed set experiments are given.
A 1 Gs/S, 31 Mhz Bw, 76.3 Db Dynamic Range, 34 Mw Ct-Δς Adc With 1.5 Cycle Quantizer Delay And Improved Stf, Sakkarapani Balagopal, Kehan Zhu, Vishal Saxena
A 1 Gs/S, 31 Mhz Bw, 76.3 Db Dynamic Range, 34 Mw Ct-Δς Adc With 1.5 Cycle Quantizer Delay And Improved Stf, Sakkarapani Balagopal, Kehan Zhu, Vishal Saxena
Electrical and Computer Engineering Faculty Publications and Presentations
A 1 GS/s continuous-time delta-sigma modulator (CT- ΔΣM) with 31 MHz bandwidth, 76.3 dB dynamic range and 72.5 dB peak-SNDR is reported in a 0.13 μm CMOS technology. The design employs an excess loop delay (ELD) of more than one clock cycle for achieving higher sampling rate. The ELD is compensated using a fast-loop formed around the last integrator by using a sample-and-hold. Further, the effect of this ELD compensation scheme on the signal transfer function (STF) of a feedforward CT- ΔΣ architecture has been analyzed and reported. In this work, an improved STF is achieved by using a combination …
A Low-Cost Wireless Portable Particulate Matter Monitoring System, Sin Ming Loo, James A. Hall, Joshua Kiepert, Michael Pook, Nicholas Terrell
A Low-Cost Wireless Portable Particulate Matter Monitoring System, Sin Ming Loo, James A. Hall, Joshua Kiepert, Michael Pook, Nicholas Terrell
Electrical and Computer Engineering Faculty Publications and Presentations
This paper describes a portable sensor system design for environmental research. The designed system has been deployed in many environments and has been EMI/EMC approved for operation in commercial aircraft cabins. The sensor suite includes particulate matter, CO, CO2, temperature, humidity, pressure, light intensity, and sound sensors. Multiple sensor systems can be deployed at once to form a wireless sensor network. Each sensor node is powered either with six AA batteries or via a transformer and standard outlet. The data collected by a node can be stored locally on the device and/or sent through the integrated ZigBee mesh network to …
Timing And Carrier Synchronization With Channel Estimation In Af Two-Way Relaying Networks, Ali A. Nasir, Hani Mehrpouyan, Salman Durrani, Steven D. Bolstein, Rodney A. Kennedy
Timing And Carrier Synchronization With Channel Estimation In Af Two-Way Relaying Networks, Ali A. Nasir, Hani Mehrpouyan, Salman Durrani, Steven D. Bolstein, Rodney A. Kennedy
Electrical and Computer Engineering Faculty Publications and Presentations
Two-way relaying networks (TWRNs) allow for more bandwidth efficient use of the available spectrum since they allow for simultaneous information exchange between two users with the assistance of an intermediate relay node. However, due to superposition of signals at the relay node, the received signal at the user terminals is affected by multiple impairments, i.e., channel gains, timing offsets, and carrier frequency offsets, that need to be jointly estimated and compensated. This paper presents the system model for amplify-and-forward (AF) TWRNs in the presence of multiple impairments and proposes least squares and differential evolution based algorithms for joint estimation …
Rt-Dsp Using ”See Through”, Cameron H. G. Wright, Thad B. Welch, Michael G. Morrow
Rt-Dsp Using ”See Through”, Cameron H. G. Wright, Thad B. Welch, Michael G. Morrow
Electrical and Computer Engineering Faculty Publications and Presentations
Engineering educators teaching digital signal processing (DSP) have found that using hands-on exercises for students can smooth the transition from theory to practical real-time DSP. However, before significant learning can begin using such exercises, students must build their confidence in the hardware and software platforms. When using audio signals, a “talk-through” project accomplishes this. For introducing more complicated signals such as video, the authors propose the use of a “see-through” project. This paper provides a description of a see-through project on a high-performance real-time DSP platform, discusses how such a project can lead to better follow-on learning using more advanced …
Simulation Of Electron Hop Funnels Using Version 9.2 Of Lorentz-2e, Tyler Rowe, Marcus Pearlman, Jim Browning
Simulation Of Electron Hop Funnels Using Version 9.2 Of Lorentz-2e, Tyler Rowe, Marcus Pearlman, Jim Browning
Electrical and Computer Engineering Faculty Publications and Presentations
Electron hop funnels have been simulated using the new version of the particle trajectory simulation software, Lorentz-2E. Simulations were conducted to determine the validity of the version 9.2 results and the consistency of the results to a previous version of the software, version 8.0. In addition, a new method of injecting a uniform current with all rays of equal charge is discussed, and the results of the method are presented. Version 9.2 of the software was successfully implemented and a new emission model tested. The transition of the software version will allow for faster simulation times of the electron hop …