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SSC high speed communication channel and interconnects

Description: This paper investigates potential metallic and optical technology applications in SSC high speed interconnects and/or communication channels. Primary focus will be placed on evaluating several metallic and optical interconnect structures. 7 refs., 3 figs.
Date: January 1, 1990
Creator: Cooke, B.J.; Smith, R.C. & Wagner, R.
Partner: UNT Libraries Government Documents Department

Cabling for an SSC silicon tracking system

Description: As part of the Superconducting Super Collider Laboratory (SSCL) funded silicon tracking subsystem R D program, we examine the problems associated with cabling such a system. Different options for the cabling plant are discussed. A silicon microstrip tracking detector for an SSC experiment is an extremely complex system. The system consists of approximately 10{sup 7} detector channels, each of which requires a communication link with the outside world and connections to the detector bias voltage supply, to a DC power supply for the onboard electronics, and to an adjustable discrimination level. The large number of channels and the short time between beam interactions (16 nanoseconds) dictates the need for high speed and large bandwidth communication channels, and a power distribution system that can handle the high current draw of the electronics including the large AC component due to their switching. At the same time the constraints imposed by the physics measurements require that the cable plant have absolutely minimal mass and radiation length. 4 refs., 2 figs.
Date: January 1, 1990
Creator: Ziock, H.; Boissevain, J.; Cooke, B. & Miller, W.
Partner: UNT Libraries Government Documents Department

Partial removal of correlated noise in thermal imagery

Description: Correlated noise occurs in many imaging systems such as scanners and push-broom imagers. The sources of correlated noise can be from the detectors, pre-amplifiers and sampling circuits. Correlated noise appears as streaking along the scan direction of a scanner or in the along track direction of a push-broom imager. We have developed algorithms to simulate correlated noise and pre-filter to reduce the amount of streaking while not destroying the scene content. The pre- filter in the Fourier domain consists of the product of two filters. One filter models the correlated noise spectrum, the other is a windowing function e.g. Gaussian or Hanning window with variable width to block high frequency noise away from the origin of the Fourier Transform of the image data. We have optimized the filter parameters for various scenes and find improvements of the RMS error of the original minus the pre-filtered noisy image.
Date: April 1, 1996
Creator: Borel, C.C.; Cooke, B.J. & Laubscher, B.E.
Partner: UNT Libraries Government Documents Department

Feasibility of microwave interferometry and fourier-transform spectrometry for high-spectral-resolution sensing

Description: This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The primary objective of this project was to perform the necessary research and development to determine the feasibility of new ideas that, if successful, could lead to the development of future new programs in high-spectral resolution remote sensing. In active remote sensing systems, the solar illumination of a scene is replaced by a man-made source, preferably a laser beam. However, when laser beams are propagated through a scattering medium, like air, random optical path fluctuations comparable to the optical wavelength are generated giving rise to the speckle effect, which is the most severe perturbation in active remote sensing systems. The limitations introduced by the speckle effect degrade or negate the data interpretation. We sought to introduce better physical models of beam scattering that allow a more realistic simulation environment to be developed that, when applied to experimental data sets, improve their interpretability and increase the information content. Improved beam propagation models require improved knowledge of the spatio-temporal distribution of the scattering and absorbing medium. In the free atmosphere the largest contributor is water vapor in the lower troposphere. We tested the feasibility of using microwave interferometry to measure water-vapor irregularities in the boundary layer. Knowledge of these distributions enable much improved atmospheric correction algorithms for satellite imagery of the earth`s surface to be developed. For hyperspectral active remote sensing systems it is necessary to perform very high-resolution spectral measurements of the reflected laser light. Such measurements are possible with optical interferometers.
Date: September 1, 1996
Creator: Gerstl, S.; Cooke, B.; Jacobson, A.; Love, S. & Zardecki, A.
Partner: UNT Libraries Government Documents Department

Analysis and design methodology for the development of optimized, direct-detection CO{sub 2} DIAL receivers

Description: The analysis methodology and corresponding analytical tools for the design of optimized, low-noise, hard target return CO{sub 2} Differential Absorption Lidar (DIAL) receiver systems implementing both single element detectors and multi-pixel imaging arrays for passive/active, remote-sensing applications are presented. System parameters and components composing the receiver include: aperture, focal length, field of view, cold shield requirements, image plane dimensions, pixel dimensions, pixel pitch and fill factor, detection quantum efficiency, optical filter requirements, amplifier and temporal sampling parameters. The performance analysis is accomplished by calculating the system`s CO{sub 2} laser range response, total noise, optical geometric form factor and optical resolution. The noise components include speckle, photon noise due to signal, scene and atmospheric background, cold shield, and electronic noise. System resolution is simulated through cascaded optical transfer functions and includes effects due to atmosphere, optics, image sampling, and system motion. Experimental results of a developmental single-element detector receiver designed to detect 100 ns wide laser pulses (10 - 100 kHz pulse repetition rates) backscattered from hard-targets at nominal ranges of 10 km are presented. The receiver sensitivity is near-background noise limited, given an 8.5-11.5 {mu}m radiant optical bandwidth, with the total noise floor spectrally white for maximum pulse averaging efficiency.
Date: December 31, 1996
Creator: Cooke, B.J.; Laubscher, B.E. & Cafferty, M.
Partner: UNT Libraries Government Documents Department

LANL receiver system development

Description: The CALIOPE receiver system development at LANL is the story of two technologies. The first of these technologies consists of off-the-shelf mercury-cadmium-telluride (MCT) detectors and amplifiers. The vendor for this system is Kolmar Technologies. This system was fielded in the Tan Trailer I (TTI) in 1995 and will be referred to in this paper as GEN I. The second system consists of a MCT detector procured from Santa Barbara Research Center (SBRC) and an amplifier designed and built by LANL. This system was fielded in the Tan Trailer II (TTII) system at the NTS tests in 1996 and will be referred to as GEN II. The LANL CALIOPE experimental plan for 1996 was to improve the lidar system by progressing to a higher rep rate laser to perform many shots in a much shorter period of time. In keeping with this plan, the receiver team set a goal of developing a detector system that was background limited for the projected 100 nanosecond (ns) laser pulse. A set of detailed simulations of the DIAL lidar experiment was performed. From these runs, parameters such as optimal detector size, field of view of the receiver system, nominal laser return power, etc. were extracted. With this information, detector physics and amplifier electronic models were developed to obtain the required specifications for each of these components. These derived specs indicated that a substantial improvement over commercially available, off-the-shelf, amplifier and detector technologies would be needed to obtain the goals. To determine if the original GEN I detector was usable, the authors performed tests on a 100 micron square detector at cryogenic temperatures. The results of this test and others convinced them that an advanced detector was required. Eventually, a suitable detector was identified and a number of these single element detectors were procured from SBRC. ...
Date: August 1, 1997
Creator: Laubscher, B.; Cooke, B.; Cafferty, M. & Olivas, N.
Partner: UNT Libraries Government Documents Department

Remote sensing science - new concepts and applications

Description: This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The science and technology of satellite remote sensing is an emerging interdisciplinary field that is growing rapidly with many global and regional applications requiring quantitative sensing of earth`s surface features as well as its atmosphere from space. It is possible today to resolve structures on the earth`s surface as small as one meter from space. If this high spatial resolution is coupled with high spectral resolution, instant object identification can also be achieved. To interpret these spectral signatures correctly, it is necessary to perform a computational correction on the satellite imagery that removes the distorting effects of the atmosphere. This project studied such new concepts and applied innovative new approaches in remote sensing science.
Date: October 1, 1996
Creator: Gerstl, S.A.; Cooke, B.J.; Henderson, B.G.; Love, S.P. & Zardecki, A.
Partner: UNT Libraries Government Documents Department

Analysis and System Design Framework for Infrared Spatial Heterodyne Spectrometers

Description: The authors present a preliminary analysis and design framework developed for the evaluation and optimization of infrared, Imaging Spatial Heterodyne Spectrometer (SHS) electro-optic systems. Commensurate with conventional interferometric spectrometers, SHS modeling requires an integrated analysis environment for rigorous evaluation of system error propagation due to detection process, detection noise, system motion, retrieval algorithm and calibration algorithm. The analysis tools provide for optimization of critical system parameters and components including : (1) optical aperture, f-number, and spectral transmission, (2) SHS interferometer grating and Littrow parameters, and (3) image plane requirements as well as cold shield, optical filtering, and focal-plane dimensions, pixel dimensions and quantum efficiency, (4) SHS spatial and temporal sampling parameters, and (5) retrieval and calibration algorithm issues.
Date: April 5, 1999
Creator: Cooke, B.J.; Smith, B.W.; Laubscher, B.E.; Villeneuve, P.V. & Briles, S.D.
Partner: UNT Libraries Government Documents Department

Low-noise detector and amplifier design for 100 ns direct detection CO{sub 2} LIDAR receiver

Description: The development and test results of a prototype detector/amplifier design for a background limited, pulsed 100 ns, 10--100 kHz repetition rate LIDAR/DIAL receiver system are presented. Design objectives include near-matched filter detection of received pulse amplitude and round trip time-of-flight, and the elimination of excess correlated detector/amplifier noise for optimal pulse averaging. A novel pole-zero cancellation amplifier, coupled with a state-of-the-art SBRC (Santa Barbara Research Center) infrared detector was implemented to meet design objectives. The pole-zero cancellation amplifier utilizes a tunable, pseudo-matched filter technique to match the width of the laser pulse to the shaping time of the filter for optimal SNR performance. Low frequency correlated noise, (l/f and drift noise) is rejected through a second order high gain feedback loop. The amplifier also employs an active detector bias stage minimizing detector drift. Experimental results will be provided that demonstrate near-background limited, 100 ns pulse detection performance given a 8.5--11.5 {micro}m (300 K B.B.) radiant background, with the total noise floor spectrally white for optimal pulse averaging efficiency.
Date: June 1, 1997
Creator: Cafferty, M.M.; Cooke, B.J.; Laubscher, B.E.; Olivas, N.L. & Fuller, K.
Partner: UNT Libraries Government Documents Department

CO{sub 2} dial transmitter/receiver noise characterization and related correlated noise issues

Description: Our approach concerning the development of hard target return CO{sub 2} DIAL transmitter/receiver systems is two phased- (i) through analysis and experiment, develop a fundamental understanding of the transmitter/receiver physics specific to DIAL systems and (ii) apply these fundamentals in the development of optimal performance DIAL transmitter/receiver systems. We present our progress and results towards these objectives with the following topics addressed: A general overview of the DIAL transmitter/receiver system characterization effort with a focus on transceiver noise processes. The effects of correlated noise on DIAL performance, especially those effecting statistical convergence over long sample structures, is , introduced. And, preliminary measurements of a low-noise, ``white`` receiver prototype are presented.
Date: February 1, 1996
Creator: Cooke, B.; Schmitt, M.; Goeller, R.; Czuchlewski, S.; Fuller, K.; Olivas, N. et al.
Partner: UNT Libraries Government Documents Department

Coherent electromagnetic field imaging through Fourier transform heterodyne

Description: The authors present a detection process capable of directly imaging the transverse amplitude, phase, and if desired, Doppler shift of coherent electromagnetic fields. Based on coherent detection principles governing conventional heterodyned RADAR/LIDAR systems, Fourier Transform Heterodyne (FTH) incorporates transverse spatial encoding of the local oscillator for image capture. Appropriate selection of spatial encoding functions, or basis set, allows image retrieval by way of classic Fourier manipulations. Of practical interest: (1) imaging is accomplished on a single element detector requiring no additional scanning or moving components, and (2) a wide variety of appropriate spatial encoding functions exist that may be adaptively configured in real-time for applications requiring optimal detection. In this paper, they introduce the underlying principles governing FTH imaging, followed by demonstration of concept via a simple experimental setup based on a HeNe laser and a 69 element spatial phase modulator.
Date: December 1998
Creator: Cooke, B. J.; Laubscher, B. E.; Olivas, N. L.; Goeller, R. M.; Cafferty, M.; Briles, S. D. et al.
Partner: UNT Libraries Government Documents Department

Design Considerations, Modeling and Analysis for the Multispectral Thermal Imager

Description: The design of remote sensing systems is driven by the need to provide cost-effective, substantive answers to questions posed by our customers. This is especially important for space-based systems, which tend to be expensive, and which generally cannot be changed after they are launched. We report here on the approach we employed in developing the desired attributes of a satellite mission, namely the Multispectral Thermal Imager. After an initial scoping study, we applied a procedure which we call: "End-to-end modeling and analysis (EEM)." We began with target attributes, translated to observable signatures and then propagated the signatures through the atmosphere to the sensor location. We modeled the sensor attributes to yield a simulated data stream, which was then analyzed to retrieve information about the original target. The retrieved signature was then compared to the original to obtain a figure of merit: hence the term "end-to-end modeling and analysis." We base the EEM in physics to ensure high fidelity and to permit scaling. As the actual design of the payload evolves, and as real hardware is tested, we can update the EEM to facilitate trade studies, and to judge, for example, whether components that deviate from specifications are acceptable.
Date: February 1, 1999
Creator: Borel, C.C.; Clodius, W.B.; Cooke, B.J.; Smith, B.W. & Weber, P.G.
Partner: UNT Libraries Government Documents Department

Laser Field Imaging Through Fourier Transform Heterodyne

Description: The authors present a detection process capable of directly imaging the transverse amplitude, phase, and Doppler shift of coherent electromagnetic fields. Based on coherent detection principles governing conventional heterodyned RADAR/LADAR systems, Fourier Transform Heterodyne incorporates transverse spatial encoding of the reference local oscillator for image capture. Appropriate selection of spatial encoding functions allows image retrieval by way of classic Fourier manipulations. Of practical interest: (1) imaging may be accomplished with a single element detector/sensor requiring no additional scanning or moving components, (2) as detection is governed by heterodyne principles, near quantum limited performance is achievable, (3) a wide variety of appropriate spatial encoding functions exist that may be adaptively configured in real-time for applications requiring optimal detection, and (4) the concept is general with the applicable electromagnetic spectrum encompassing the RF through optical.
Date: April 5, 1999
Creator: Cooke, B.J.; Laubscher, B.E.; Olivas, N.L.; Galbraith, A.E.; Strauss, C.E. & Grubler, A.C.
Partner: UNT Libraries Government Documents Department

Efficient data transmission from silicon wafer strip detectors

Description: An architecture for on-wafer processing is proposed for central silicon-strip tracker systems as they are currently designed for high energy physics experiments at the SSC, and for heavy ion experiments at RHIC. The data compression achievable with on-wafer processing would make it possible to transmit all data generated to the outside of the detector system. A set of data which completely describes the state of the wafer for low occupancy events and which contains important statistical information for more complex events can be transmitted immediately. This information could be used in early trigger decisions. Additional data packages which complete the description of the state of the wafer vary in size and are sent through a second channel. By buffering this channel the required bandwidth can be kept far below the peak data rates which occur in rate but interesting events. 18 refs.
Date: January 1, 1991
Creator: Cooke, B.J.; Lackner, K.S.; Palounek, A.P.T.; Sharp, D.H.; Winter, L. & Ziock, H.J.
Partner: UNT Libraries Government Documents Department

Efficient data transmission from silicon wafer strip detectors

Description: An architecture for on-wafer processing is proposed for central silicon-strip tracker systems as they are currently designed for high energy physics experiments at the SSC, and for heavy ion experiments at RHIC. The data compression achievable with on-wafer processing would make it possible to transmit all data generated to the outside of the detector system. A set of data which completely describes the state of the wafer for low occupancy events and which contains important statistical information for more complex events can be transmitted immediately. This information could be used in early trigger decisions. Additional data packages which complete the description of the state of the wafer vary in size and are sent through a second channel. By buffering this channel the required bandwidth can be kept far below the peak data rates which occur in rate but interesting events. 18 refs.
Date: December 31, 1991
Creator: Cooke, B. J.; Lackner, K. S.; Palounek, A. P. T.; Sharp, D. H.; Winter, L. & Ziock, H. J.
Partner: UNT Libraries Government Documents Department

Measurement Strategies for Remote Sensing Applications

Description: Remote sensing has grown to encompass many instruments and observations, with concomitant data from a huge number of targets. As evidenced by the impressive growth in the number of published papers and presentations in this field, there is a great deal of interest in applying these capabilities. The true challenge is to transition from directly observed data sets to obtaining meaningful and robust information about remotely sensed targets. We use physics-based end-to-end modeling and analysis techniques as a framework for such a transition. Our technique starts with quantified observables and signatures of a target. The signatures are propagated through representative atmospheres to realistically modeled sensors. Simulated data are then propagated through analysis routines, yielding measurements that are directly compared to the original target attributes. We use this approach to develop measurement strategies which ensure that our efforts provide a balanced approach to obtaining substantive information on our targets.
Date: March 6, 1999
Creator: Weber, P.G.; Theiler, J.; Smith, B.; Love, S.P.; LaDelfe, P.C.; Cooke, B.J. et al.
Partner: UNT Libraries Government Documents Department

Significant ELCAP analysis results: Summary report. [End-use Load and Consumer Assessment Program]

Description: The evolution of the End-Use Load and Consumer Assessment Program (ELCAP) since 1983 at Bonneville Power Administration (Bonneville) has been eventful and somewhat tortuous. The birth pangs of a data set so large and encompassing as this have been overwhelming at times. The early adolescent stage of data set development and use has now been reached and preliminary results of early analyses of the data are becoming well known. However, the full maturity of the data set and the corresponding wealth of analytic insights are not fully realized. This document is in some sense a milestone in the brief history of the program. It is a summary of the results of the first five years of the program, principally containing excerpts from a number of previous reports. It is meant to highlight significant accomplishments and analytical results, with a focus on the principal results. Many of the results have a broad application in the utility load research community in general, although the real breadth of the data set remains largely unexplored. The first section of the document introduces the data set: how the buildings were selected, how the metering equipment was installed, and how the data set has been prepared for analysis. Each of the sections that follow the introduction summarize a particular analytic result. A large majority of the analyses to date involve the residential samples, as these were installed first and had highest priority on the analytic agenda. Two exploratory analyses using commercial data are included as an introduction to the commercial analyses that are currently underway. Most of the sections reference more complete technical reports which the reader should refer to for details of the methodology and for more complete discussion of the results. Sections have been processed separately for inclusion on the data base.
Date: February 1, 1991
Creator: Pratt, R.G.; Conner, C.C.; Drost, M.K.; Miller, N.E.; Cooke, B.A.; Halverson, M.A. et al.
Partner: UNT Libraries Government Documents Department