A brief introduction to the 2-D geometrical theory of diffraction (GTD) propagation prediction model (PPM) is presented. The author describes the application of this model to predicting channel phase, signal attenuati...
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A brief introduction to the 2-D geometrical theory of diffraction (GTD) propagation prediction model (PPM) is presented. The author describes the application of this model to predicting channel phase, signal attenuation versus frequency, and the use of the fast Fourier transform to predict the channel impulse response from the GTD PPM predictions. The signal delay and delay spread values are computed. The results provide a powerful addition to the tools available to the RF engineer for digital system performance predictions.
Engineers responsible for designing and operating large industrial facilities are relying increasingly on computer modeling to evaluate the steady state and transient operating characteristics of electrical power syst...
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Engineers responsible for designing and operating large industrial facilities are relying increasingly on computer modeling to evaluate the steady state and transient operating characteristics of electrical power systems. Innovative concepts which demonstrate the users' ability to evaluate a great number of system options and provide an enhanced understanding of the transient and steady state performance of power systems are presented. Data are presented to show the time savings in performing some typical tasks. Examples are provided showing how understanding the results of computer output is improved. The concepts presented make effective tools for the study of large power systems on a personal computer.< >
Photovoltaic power systems normally use a maximum power point tracker (MPT) to continuously deliver the highest possible power to the load when there are changes in insolation and temperature. Due to the MPT's cha...
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Photovoltaic power systems normally use a maximum power point tracker (MPT) to continuously deliver the highest possible power to the load when there are changes in insolation and temperature. Due to the MPT's characteristics there is no longer a constant voltage available at the bus. If this load is a DC motor with a separately-excited field winding, the motor's efficiency drops considerably unless operated at its rated values. To alter the motor's efficiency, the only variable which can be altered is the field voltage by a buck-boost converter. An optimum field voltage is sought. This paper describes a drive system controlled by a 96002 digital signal processor to obtain the optimum efficiency for any input power level under complex conditions of changing terminal voltage which is itself a function of the field setting.< >
The author describes an algorithm for finding part of a Kronecker power matrix without computing the whole matrix. Two definitions are provided. The algorithm for finding a submatrix and its proof are described.
The author describes an algorithm for finding part of a Kronecker power matrix without computing the whole matrix. Two definitions are provided. The algorithm for finding a submatrix and its proof are described.< >
The capacity C/sub ZF/ of an idealized zero-forcing decision-feedback equalization (ZF-DFE) system is compared to the capacity C of the underlying Gaussian-noise channel. It is found that, for strictly band-limited ch...
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The capacity C/sub ZF/ of an idealized zero-forcing decision-feedback equalization (ZF-DFE) system is compared to the capacity C of the underlying Gaussian-noise channel. It is found that, for strictly band-limited channels, the capacity penalty gets vanishingly small as the signal power increases. For nonstrictly band-limited channels, the capacity difference C - C/sub ZF/ grows without bound as the signal power increases, and the asymptotic ratio C/sub ZFC/ is as low as 93.6% for some channels. It is concluded that ZF-DFE on nonstrictly band-limited channels is a suboptimal, information-lossy equalization technique, even in the limit of infinite signal power.< >
A process for constructing an information workspace with low-cost access to reusable analysis and design knowledge has been developed and validated. The intent is to support the design and evolution of product familie...
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A process for constructing an information workspace with low-cost access to reusable analysis and design knowledge has been developed and validated. The intent is to support the design and evolution of product families. The process involves three related efforts: techniques to consolidate critical analysis and design information-domain analysis; organization of the information in structured form-technology books; and methods and tools to reuse information. It is concluded that a process for consolidating and reusing design knowledge is powerful by itself, and in the authors' engineering domains, the reuse of analyses and designs is more useful than the reuse of software.< >
A new technique for enhancing correlation discrimination is achieved by using a fringe-adjusted joint transform correlator (JTC). This technique is found to yield significantly better correlation output than the class...
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A new technique for enhancing correlation discrimination is achieved by using a fringe-adjusted joint transform correlator (JTC). This technique is found to yield significantly better correlation output than the classical and binary JTCs. It also avoids the computation intensive joint power spectrum binarization processing of a binary JTC.< >
power quality is an increasing concern of electric utilities due to growing consumer use of solid-state devices, including computers and microprocessors, in equipment such as microwave ovens, stereos, TVs, and VCRs. P...
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power quality is an increasing concern of electric utilities due to growing consumer use of solid-state devices, including computers and microprocessors, in equipment such as microwave ovens, stereos, TVs, and VCRs. power quality is generally interpreted to include a broad listing of items, including RMS voltage, harmonics, average outage times, momentary interruptions, line flicker, and other values. Line flicker due to motor starting and loading is reviewed. Equipment for measuring flicker, methods for calculating flicker, and four cases involving motor flicker are also reviewed.< >
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