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Negative Conductance Power Amplifier, Vladimir I. Prodanov
Negative Conductance Power Amplifier, Vladimir I. Prodanov
Electrical Engineering
Power amplifiers are disclosed that demonstrate improved linearity and efficiency in applications requiring significant peak-to-average ratios (PAR). A power amplifier in accordance with the present invention comprises a first transistor in an input stage that converts DC power into AC power; and a second transistor in a negative conductance stage that has a current-voltage characteristic with at least two slopes. The at least two slopes of the current-voltage characteristic are separated by a break point that may be controlled. The power amplifier may also include a non-dissipative two-port device that has two AC ports. The non-dissipative two-port device has a …
Power Electronic Courses That Work, Taufik
Power Electronic Courses That Work, Taufik
Electrical Engineering
This paper presents approaches that have been implemented in power electronic courses to be more appealing to electrical engineering students and hence increase their enrollments. The approaches entail redesigning the structure and content of the courses along with developing new laboratory experiments to better align the lab with the lecture portion of the courses and to reflect recent practical issues in power electronics. In addition to lab experiments, the redesigned courses provide students with an opportunity to apply their knowledge in assigned hardware projects that illustrated many of the points learned in the lecture portion of the course with increasing …
Electromagnetic Crosstalk Penalty In 2.5gb/S And 10gb/S Serial Optical Modules, Xiaomin Jin, Fei Wang, Keith D. Lystad, Musoke H. Sendaula
Electromagnetic Crosstalk Penalty In 2.5gb/S And 10gb/S Serial Optical Modules, Xiaomin Jin, Fei Wang, Keith D. Lystad, Musoke H. Sendaula
Electrical Engineering
Electromagnetic crosstalk poses a serious problem in advanced serial communication modules. This paper focuses on the primary sources of crosstalk penalty in a 2.5 Gb/s optic transceiver and a 1OGb/s optic transponder. A novel method to quantify the crosstalk penalty by observing a receiver's bit-error-ratio (BER) versus transmitter to receiver signal phase is proposed. A coupled microstrip transmission line model is also explored to demonstrate inductive crosstalk coupling.
Characterization Of Error-Tolerant Applications When Protecting Control Data, Darshan D. Thaker, Diana Franklin, John Y. Oliver, Susmit Biswas, Derek Lockhart, Tzvetan Metodi, Frederic T. Chong
Characterization Of Error-Tolerant Applications When Protecting Control Data, Darshan D. Thaker, Diana Franklin, John Y. Oliver, Susmit Biswas, Derek Lockhart, Tzvetan Metodi, Frederic T. Chong
Electrical Engineering
Soft errors have become a significant concern and recent studies have measured the "architectural vulnerability factor" of systems to such errors, or conversely, the potential that a soft error is masked by latches or other system behavior. We take soft-error tolerance one step further and examine when an application can tolerate errors that are not masked. For example, a video decoder or approximation algorithm can tolerate errors if the user is willing to accept degraded output. The key observation is that while the decoder can tolerate error in its data, it can not tolerate error in its control. We first …
A Data Fusion Approach To Automated Vehicle Detector Testing, C. A. Maccarley, N. Nesse, J. Slonaker
A Data Fusion Approach To Automated Vehicle Detector Testing, C. A. Maccarley, N. Nesse, J. Slonaker
Electrical Engineering
Vehicle presence detectors have become critical elements of traffic management systems, including applications ranging from intersection signal control to freeway congestion monitoring. The need to assess the accuracy and attributes of each of the many types of sensors motivated the California Department of Transportation to construct the Traffic Detector Testbed on I-405 in Southern California. With up to ten detectors of different types under concurrent test in each of six lanes, a means for automating the testing process became imperative, since traditional human-verification methods were not practical. This paper describes the design and implementation of an automated data acquisition and …
Structural Matching Via Optimal Basis Graphs, Fred W. Depiero
Structural Matching Via Optimal Basis Graphs, Fred W. Depiero
Electrical Engineering
The ‘basis graph’ approach to structural matching uses a fixed set of small (4 node) graphs to characterize local structure. We compute mapping probabilities by first finding the probability of a basis graph being an induced subgraph of the input graph. The similarity of these probabilities is used to compare nodes of the input graphs. The method permits common subgraphs to be identified without the use of any node or edge coloring. We report on an improved, simpler, version of the algorithm, which has also been optimized. Performance is compared with the LeRP method, which is based on length-r paths. …
Stochastic Adaptive Control Model For Traffic Signal Systems, Xiao-Hua Yu, W. W. Recker
Stochastic Adaptive Control Model For Traffic Signal Systems, Xiao-Hua Yu, W. W. Recker
Electrical Engineering
An adaptive control model of a network of signalized intersections is proposed based on a discrete-time, stationary, Markov decision process. The model incorporates probabilistic forecasts of individual vehicle actuations at downstream inductance loop detectors that are derived from a macroscopic link transfer function. The model is tested both on a typical isolated traffic intersection and a simple network comprised of five four-legged signalized intersections, and compared to full-actuated control. Analyses of simulation results using this approach show significant improvement over traditional full-actuated control, especially for the case of high volume, but not saturated, traffic demand.
Automatic Biasing Of A Power Device For Linear Operation, Vladimir I. Prodanov
Automatic Biasing Of A Power Device For Linear Operation, Vladimir I. Prodanov
Electrical Engineering
A power device(s) is biased and operates in Class-AB. Crossover distortion is minimized over a broad range of operating conditions, not only for a nominal case. The bias current of a power transistor is automatically adjusted in response to process and temperature variations. Preferably, the adjustment is performed using an error-feedback arrangement. An exemplary ‘rule’ for bias adjustment involves satisfying a proportionality relationship between the small-signal device transconductance at the operating point, and a maximum device transconductance. A dual replica master-slave control architecture is utilized. A self-adapting circuit is provided to change the bias current (or voltage) so that the …
Parallel Operation Of Hybrid Loaded Resonant Converter Using Phase-Shift Control, Taufik, James J. Mullins
Parallel Operation Of Hybrid Loaded Resonant Converter Using Phase-Shift Control, Taufik, James J. Mullins
Electrical Engineering
This paper presents a phase shifting method to adjust the combined output voltage of two hybrid loaded resonant converters connected in parallel. The method implements a fixed switching frequency and hence it is particularly useful in applications such as medical instrumentation where audible noise is not desirable. The design and analysis of parallel hybrid resonant converters operating in discontinuous conduction mode using the phase shifting method is described. Computer simulation to prove the feasibility of the phase shifting method in the design example is also provided. Analysis of the characteristics of the output voltage produced by phase shifting control along …
A Miniature 5.5 Amp Dc Motor Drive, Taufik, Edwin Tahlman
A Miniature 5.5 Amp Dc Motor Drive, Taufik, Edwin Tahlman
Electrical Engineering
This paper details the design process and the stages of construction of a 12 V 5.5 A DC motor drive on a very small 1.5 inches by 1.5 inches printed circuit board. The relatively small-size but high power dc motor drive may open door to a wide spectrum of industrial electronic applications. The tiny size was made possible by the latest technology in power electronics for integrated dc motor drive technology and was aimed to improve overall efficiency of the dc motor drive circuit. A laboratory prototype was built and loading tests and measurements were conducted. The results of these …
Rotorcraft Acoustic Noise Estimation And Outlier Detection, Johnny Fu, Xiao-Hua Yu
Rotorcraft Acoustic Noise Estimation And Outlier Detection, Johnny Fu, Xiao-Hua Yu
Electrical Engineering
This paper focuses on the application of artificial neural networks for rotorcraft acoustic data modeling, prediction, and outlier detection. The original data is recorded by microphones mounted inside a wind tunnel at NASA Ames Research Center, Moffett Field, CA. The experimental data is first acquired in the time-domain as a time history measurement; then the sound pressure level (SPL) that represents the acoustic noise in frequency domain is derived from the time history dataset. In this study, neural networks based models are developed in both time domain and frequency domain. Outlier detection is then performed using modified Z-scores for SPL …
Bandwidth Enhancement Of Fabry-Perot Quantum-Well Lasers By Injection-Locking, Xiaomin Jin, Shun-Lien Chuang
Bandwidth Enhancement Of Fabry-Perot Quantum-Well Lasers By Injection-Locking, Xiaomin Jin, Shun-Lien Chuang
Electrical Engineering
Theory and experiment for dc and small-signal electrical modulation of an injection-locked quantum-well (QW) Fabry-Perot laser are presented. Our experiment is realized by performing side-mode injection locking of a multiple-quantum-well (MQW) InGaAsP Fabry-Perot (FP) laser, which has the advantage of optical wavelength conversion. We first measure the dc characteristics and optical spectra of an injection-locked laser to define its locking range and linewidth enhancement factor. We then show experimentally that the bandwidth of an injection-locked semiconductor laser is 10.5 GHz, which is around twice the free-running electrical modulation bandwidth (5.3 GHz). The relaxation frequency of the injection-locked laser can be …
Tile Size Selection For Low-Power Tile-Based Architectures, John Y. Oliver, Ravishankar Rao, Michael Brown, Jennifer Mankin, Diana Franklin, Frederic T. Chong, Venkatesh Akella
Tile Size Selection For Low-Power Tile-Based Architectures, John Y. Oliver, Ravishankar Rao, Michael Brown, Jennifer Mankin, Diana Franklin, Frederic T. Chong, Venkatesh Akella
Electrical Engineering
In this paper, we investigate the power implications of tile size selection for tile-based processors. We refer to this investigation as a tile granularity study. This is accomplished by distilling the architectural cost of tiles with different computational widths into a system metric we call the Granularity Indicator (GI). The GI is then compared against the communications exposed when algorithms are partitioned across multiple tiles. Through this comparison, the tile granularity that best fits a given set of algorithms can be determined, reducing the system power for that set of algorithms. When the GI analysis is applied to the Synchroscalar …
Study Of Optical-Feedback Using An Integrated Laser-Modulator/Amplifier Device, Xiaomin Jin, A. Hsu, Shun Lien Chuang
Study Of Optical-Feedback Using An Integrated Laser-Modulator/Amplifier Device, Xiaomin Jin, A. Hsu, Shun Lien Chuang
Electrical Engineering
We study optical-feedback effects using an integrated laser-modulator/amplifier. Our experiment and theory are agree well and provide interesting results of feedback effects on optical spectrum, spatial-hole burning, the photon density profile, and the microwave modulation.
System And Method For An If-Sampling Transceiver, Jack P. Glas, Vladimir I. Prodanov
System And Method For An If-Sampling Transceiver, Jack P. Glas, Vladimir I. Prodanov
Electrical Engineering
The present invention is directed toward a radio, and method for receiving radio frequency signals. The radio comprises an input signal at a first intermediate frequency, an intermediate sampling architecture, a quantizer and a baseband converter. The intermediate frequency sampling architecture comprises receiving the input signal, passing the first intermediate frequency signal through a first filter characterized by steep selectivity and narrow bandpass, converting the filtered signal to a second intermediate frequency and passing the second intermediate frequency signal through a second filter having a bandpass characteristic, but without the steep selectivity characterizing the first filter. The radio further comprises …
A 32-Mw 320-Mhz Continuous-Time Complex Delta-Sigma Adc For Multi-Mode Wireless-Lan Receivers, Jesus Arias, Peter Kiss, Vladimir Prodanov, Vito Boccuzzi, Mihai Banu, David Bisbal, Jacinto San Pablo, Luis Quintanilla, Juan Barbolla
A 32-Mw 320-Mhz Continuous-Time Complex Delta-Sigma Adc For Multi-Mode Wireless-Lan Receivers, Jesus Arias, Peter Kiss, Vladimir Prodanov, Vito Boccuzzi, Mihai Banu, David Bisbal, Jacinto San Pablo, Luis Quintanilla, Juan Barbolla
Electrical Engineering
We present an experimental continuous-time complex delta-sigma multi-bit modulator, implemented in standard 0.25-μm CMOS technology and meeting all major requirements for application in IEEE 802.11a/b/g wireless LAN receivers. The clock frequency is 320 MHz, producing an oversampling ratio of 16 for 20 MHz channel bandwidths. The modulator supports two operation modes for zero-IF and low-IF receiver architectures respectively, requires a single 2.5-V power supply, and dissipates only 32 mW of power. The measured peak signal-to-noise ratio is 55 dB. Further experimental results using sine-wave and OFDM test signals are also presented
Design Of A Low-Cost Acoustic Modem For Moored Oceanographic Applications, Bridget Benson, Grace Chang, Derek Manov, Brian Graham, Ryan Kastner
Design Of A Low-Cost Acoustic Modem For Moored Oceanographic Applications, Bridget Benson, Grace Chang, Derek Manov, Brian Graham, Ryan Kastner
Electrical Engineering
This paper discusses the current state of the art systems of real time telemetry on oceanographic moorings and describes the design requirements for making acoustic modem data telemetry a more widely used form of data telemetry for moored oceanographic applications. We present the design of a low cost ‘mooring modem’ and the results of an initial pool test for its prototype. Based on these results, we describe how the mooring modem meets the design requirements for moored oceanographic applications by looking at how it meets the requirements for a specific mooring example – the SB CHARM. We conclude by presenting …