bluuebunny/crossref_metadata_2025 huggingface dataset:
A Design Space Analysis of a Lenslet Based Optical Relay System Interconnecting Smart Pixel Arrays
Authors: Rolston D. R. , Robertson B. , Plant D. V. , Hinton H. S.
Published: February 2023

Smart Pixel based free-space optical interconnects offer a method of establishing high connection densities, and subsequently large data throughputs, in applications such as ATM networks, massively parallel computers, and photonic backplanes. The design of these optical systems require a means of quantifying the trade-offs between the effective processing power of a Smart Pixel array and the optical interconnection geometry [1,2,3]. In fight of this interest, we have developed a simple model which outlines the trade-offs between optical connection density and Smart Pixel intelligence. The objective of the model is to define a reasonable operating region where the following parameters are optimized: the number of transistors per Smart Pixel, the optoelectronic device window size, the lenslet size, the f/number of the lenslet, and the optical connection density.
FET-SEED Smart Pixels for Free-Space Digital Optics Systems
Authors: Kuznia C. B. , Sawchuk A. A. , Cheng L.
Published: February 2023

We are examining the integration of smart pixels in free space digital optics (FSDO) systems to create advanced architectures for digital optical computing. These systems consist of large arrays of electronic processing or switching nodes interconnected by optical links. We are exploring applications that require very high information input/output capacity and very high spatial information density at each processing module. FSDO offers potential improvements by increasing both the number of I/O channels per chip and the temporal bandwidth per channel. Smart pixel technology has matured enough to provide device access for practical research on the integration of these systems in an optical system. This research provides useful feedback for device makers, circuit designers, optical system designers and system architects.
Optoelectronic Communication Speedup on Mesh Processors Using Reduced Cellular Hypercube Interconnections
Authors: Lin J.-F. , Sawchuk A. A.
Published: February 2023

The mesh is one of the most popular interconnection networks for single-instruction multiple-data (SIMD) [1] array processors. For mesh-connected array processors, the communication latency is proportional to the diameter (about two times the linear size) of the array, which is the maximum number of nodes a message has to travel to reach its final destination. To decrease the diameter of the mesh, we have developed an optoelectronic reduced cellular hypercube (RCH) interconnection [2] which is combined with the mesh to form a combined network called M-RCH. In this paper, we present a time multiplexing scheme for the optoelectronic RCH and discuss the communication speedup of the M-RCH over the mesh for some common operations and applications.
High-Density 300-Gbps/cm2 Parallel Free-Space Optical Interconnection Design Considerations
Authors: Tsang Dean Z.
Published: February 2023

A high-density, high-throughput 300-Gbps/cm2 parallel free-space optical interconnection has been designed and demonstrated. The impact of component technology choices and optical, electrical, and mechanical issues will be discussed within the context of this prototype system with implications for future systems. Many of the design considerations for this prototype are common to other optical interconnection and processing systems based on arrays of components. The prototype, a linear array parallel free-space optical interconnection with up to twenty optical data paths, operated at a rate of up to 2.8 Gbps per optical data path with a delay or latency of 200 ps.
Optical Transpose Interconnection System: System Design and Component Development
Authors: Hendrick W. Lee , Marchand Philippe J. , McCormick Frederick B. , Çokgör Ilkan , Esener Sadik C.
Published: February 2023

The optical transpose interconnection system1 (OTIS) is a simple means of providing a transpose interconnection using only a pair of lenslet arrays. This system has been shown useful for shuffle based multi-stage interconnection networks, mesh-of-trees matrix processors, and hypercube interconnections. The transpose interconnection is a one-to-one interconnection between L transmitters and L receivers, where L is the product of two integers, M and N. To implement the interconnection a
N×N array of lenslets is placed in front of the input plane, and a
M×M array of lenslets is located before the output plane. The M × N transpose is equivalent to a k-shuffle2, where k equals N. For example, a 4096 channel (M = N = 64) interconnection can be implemented with two 8×8 lenslet arrays, Figure 1 shows the side view, and actual input and output for such a system. An interesting application occurs when
k=L; in this case only one stage of optics and two stages of optoelectronic switches are required for full routing between the input and output channels. If M = N, then both lenslet planes are identical; and with minor modifications, such as opaque areas on the lenses to prevent cross-talk, the system can be made bi-directional.
A universal module for split-and-join operations by cascading refractive microoptical elements
Authors: Moisei J. , Brenner K.-H.
Published: February 2023

For optical processing systems, the split and join operations are the most frequently needed operations. For an optical implementation of these operations a series of properties are favourable: The optical system should be small, modular, wavelenght tolerant and require a minimum number of different fabrication technologies.
Refractive Microprisms with improved Surface Quality by Proton Polishing
Authors: Kufher Maria , Kufher Stefan , Pichon Pierre , Chavel Pierre , Frank Michael
Published: February 2023

The fabrication of miniaturized refractive prisms for the use in free space optical systems is a relatively new field in component fabrication1,2,3. Thermal imprinting in PMMA has reduced flexibility in the angle choice and induces stress in the substrate. The optical quality of the surface is given by the quality of the master1. Synchrotron or proton irradiation of PMMA gives the advantage of arbitrary deflection angles of prisms with depths of several hundred microns. Problems arise from the fact that the roughness of a thick metal mask (>20µm) is directly copied into the prism surface2,3. This paper describes a new fabrication technique for deflection elements whose surface quality is better than the mask’s: the surface roughness is better than 20 nm. The method is based on deep proton irradiation; the new idea is that during irradiation the sample is moved relative to a fixed mask. By this a polishing effect of protons in the prism surface occurs yielding the above mentioned smoothness.
Polarization-Selective Diffractive and Computer Generated Optical Elements
Authors: Nieuborg N. , Van de Poel C. , Kirk A. , Thienpont H. , Veretennicoff I.
Published: February 2023

The growing complexity and ever-increasing miniaturization of optical systems has made the development of sophisticated, flexible and compact interconnection components both necessary and urgent [1-3]. The functionality of conventional DOEs can be increased by making them polarization-selective, i.e. anisotropic. Recently Ford et al described the fabrication and characterization of anisotropic DOEs (ADOEs) in LiNbO3-substrates using ion milling. However, to make ADOEs more generally useful, it would be desirable to use a material which is both cheaper and easier to process. Here we demonstrate that calcite is an attractive alternative, with several advantages over LiNbO3.
Cascaded optical system for holographic classification of temporal signals
Authors: Garvin C. , Wagner K.
Published: February 2023

Real-time classification of wide instantaneous bandwidth temporal signals such as radar range profiles or wideband communications signals present a challenging application to demonstrate the capabilities of adaptive, feature-based optical processing systems. In this paper we discuss progress on a nonlinearly cascaded optical neural classifier for this application. The system uses a holographic optical learning subsystem to classify time-shift invariant features computed from input wideband signals. The optical subsystems are cascaded using an optically addressed spatial light modulator (OASLM) implementing a saturating square-law nonlinearity. Through the use of two-dimensional, optically-computed trilinear input feature we take full advantage of the high space-bandwidth and high throughput processing capabilities specific to optical architectures to solve an otherwise intractable real-time signal-processing task such as wideband signal recognition. In what follows an experimental demonstration of this cascaded system is shown.
Integration of InP-Based Thin Film Emitters and Detectors Onto a Single Silicon Circuit
Authors: Camperi-Ginestet C. , Buchanan B. , Wilkinson S. , Jokerst N.M. , Brooke M.A.
Published: February 2023

Multi-material monolithic integration can be achieved through the integration of thin film compound semiconductor devices with silicon circuitry. This type of integration enables the system designer to use the optimal material to achieve the desired cost and performance requirements of the system. Silicon, the acknowledged leading technology for low cost electronics, is a particularly attractive host substrate on which to integrate thin film devices with optoelectronic capabilities. In this paper, we report the integration of InP-based emitters and detectors with a single silicon circuit which contains an emitter drive circuit and a detector amplifier circuit. These optoelectronic integrated circuits (OEICs), which operate at a wavelength of 1.3 μm, are useful as receivers and transmitters for optoelectronic interconnection schemes which include three dimensional, massively parallel computational systems using through-silicon wafer optoelectronic interconnects, grating/waveguide optical interconnection layers for multichip modules, and optical fiber.
Electrooptic Parallel Interfacing for Neural Computing and a Nonlinear Organic Spatial Light Modulator
Authors: Arima Hiroyuki , Tohyama Ichiro , Itoh Masahide , Yatagai Toyohiko , Mori Masahiko
Published: February 2023

Optical neural network computing is of great interest in terms of massively parallel computing. In recent years, CCD cameras, optoelectronic smart pixels and spatial light modulators (SLMs) with the high spatial resolution are reported[1,2]. In some cases, however, the interface between 2-D inputs and parallel neural computing systems or between the computing systems and output devices is not parallel but serial. The bandwidth of the interface between the I/O systems and the main computing system is limited and therefore this limits the performance of the total system. Such a problem is sometimes called I/O bottleneck. An all-optical parallel neural computing system with highly parallel I/O capability has been reported[3,4]. The system of the holographic associative memory, however, has limited functions and performances, because of less flexibility of optical systems. An alternative approach is to employ functional optoelectronic systems for wide-bandwidth input data, which can compress the data for the neural computing system. In this paper, we present network system consisting of an electronic parallel interface or preprocessor is described, and a generic interface device using nonlinear organic material for such a system is finally proposed.
Implementation of optical logic operations by micro-optical cascading of an array of differential PnpN-thyristor pairs
Authors: Brenner Karl-Heinz , Eckert Werner , Göbel Edwin , McArdle Neil , Moisei Jörg , Passon Christoph
Published: February 2023

The implementation of optical logic operations has been studied widely and was demonstrated in various types of systems [1,2,3]. A major goal for implementing these types of systems in future applications is miniaturization and integration. A design for an integrated version of an optical symbolic substitution system, which can be implemented with existing micro-optical components, was presented recently [4]. In this paper, as a first step towards a fully integrated system, we demonstrate basic logic operations on an array by cascading two active devices.
Analog Accuracy in Optical Vector-Matrix Processors
Authors: Carter James A. , Sunderlin Tim A. , Wasilousky Peter A. , Pape Dennis R.
Published: February 2023

Optical matrix processors were developed to exploit the high degree of parallel connectivity inherent in free space optical interconnection. Researchers have proposed and investigated optical algebra processors for at least three decades1,2. Recent advances in multi-channel modulators’ vertical cavity surface emitting laser (VCSEL) diode arrays, light valve technology, and detectors have potential to make these systems practical for many applications. Specifically, vector-matrix processing can give much higher throughput than digital approaches and many applications exist were performance can be bought with speed even at the price of accuracy or dynamic range3,4.
The Fractional Fourier Transform in Optics: Do we need it? Is it useful?
Authors: Lohmann Adolf W. , Mendlovic David , Ozaktas Haldun M.
Published: February 2023

Several respected colleges and anonymous reviewers asked us: is the fractional Fourier transform (FRT) more than a modified Fresnel transform (FRS)? Our answer is yes, the FRT is in our opinion a worthy addition to the class of transformations in optics. To understand our belief it might be useful to re call, why we invented the optical FRT, actually twice, at first in the context of GRIN fiber optics (1) and then as a linear centerpiece to sketch how the FRT could have been invented as a special case of A. E. siegman's integral transform, or as a special case of J. Shamir's operator optics. Those two authors could have invented easily the FRT, if the need to do so had arisen. We mention those two almost-inventions in order to present family features of various optical transforms. Furthermore, this sideline of our arguments is useful as preparation for answering the question; which one of all those transforms is most fundamental? We will propose four criteria for measuring the fundamentality. In our opinion, all four criteria are subjective in nature. In other words, a statement like: transform A is merely a modification of transform B, has no universal validity.
The History of Optical Computing : A Personal Perspective
Authors: Lohmann Adolf W.
Published: February 2023

For me the history of optical computing can be divided into several phases, which will illustrate by examples. The phase transitions mark changes of my personal attitude towards optics in general and to information optics in particular.
Doppler LIDAR using Nd:YAG technology
Authors: Kane Thomas J. , Byer Robert L.
Published: February 2023

We have built an extremely stable diode-pumped reference oscillator, a high power single mode master oscillator, and a high gain amplifier. Progress in system integration will be described.
Speckle propagation through turbulence: its characteristics and effects
Authors: Holmes J. Fred
Published: February 2023

Atmospheric turbulence and target induced speckle can have a significant and deleterious effect on the performance of optical systems. The primary effect is to introduce a strong fluctuation in the intensity and a random perturbation of the phase of the fields at the optical receiver. This is equivalent to introducing a large noise source at the receiver; and consequently multiple samples and/or clever processing techniques are needed to accurately estimate the magnitude of the received intensity. In addition, for coherent detection schemes, the random phase and finite transverse coherence length introduced by the speckle and turbulence will limit the size of aperture that can be used. These characteristics of the speckle field after propagation through turbulence and its effect on optical systems will be discussed in a tutorial overview.
Measurements of the pressure shift of water vapor absorption lines by simultaneous photoacoustic spectroscopy
Authors: Bösenberg J.
Published: February 2023

Measurements of the pressure shift of water vapor absorption lines have so far only been reported for very few lines in the 5 μm spectral region (1). Such measurements are required both for adjustment of model parameters in the theory of collision broadening (2)-(4) and remote sensing applications, e.g. water vapor differential absorption lidar measurements. Here it is well known that small frequency shifts of the emitted radiation produce quite large errors. The same errors could be produced by a shift of the line center with increasing height (decreasing pressure).
Measurements of Far-IR Water Vapor Absorption with an Optically Pumped Laser
Authors: Johnson John L. , Simpson Orman A.
Published: February 2023

Systems applications in the far-infrared (FIR) region of the spectrum (40 μm - 2 mm) offer several advantages over conventional microwave/millimeter and visible/infrared techniques. Specifically for a required resolution a significant reduction over microwave antenna size can be realized in the FIR, in addition to reduction of clutter return, more accurate object location, better size discrimination, and a larger bandwidth. FIR radiation also suffers less scattering losses by aerosols than the visible/infrared and can better penetrate fogs and smokes [1].
Multimodal Character of fog distribution caused by Propagation of a laser beam
Authors: El-Raey M. , Aly N.E.
Published: February 2023

The photon transfer equation of CO2 laser beam propagating through a nonuniform distribution of fog droplets is solved by finite difference technique. A multimodal character of fog distribution develops for intense beams and heavy fogs. Spatial and temporal developments of this character are investigated. Results are compared to recent distributions obtained by inversion of general remote sensing integral equation.
Absorption of Infrared Radiation by Atmospheric Water Vapor in the Region 4.3-5.5 and 8-13 Micron
Authors: Ben-Shalom A. , Devir A.D. , Lipson S.G. , Oppenheim U.P. , Ribak E.
Published: February 2023

For several years we have been making measurements of atmospheric transmittance in the wavelength region 2.8 to 15 μm under various meteorological conditions. The aim of this work was to compare experimental measurements of the transmittance with the predictions of the LOWTRAN computer codes. In this paper we present measurements of the contribution to the total atmospheric absorption made by the water-vapour continuum in the regions 4.3-5.5 μm and 8-12 μm. These contributions are included incorrectly in LOWTRAN 4 (and also in LOWTRAN 5) (1,2) and make a significant difference to the atmospheric transmittance under humid conditions or along long gorizontal paths.
Ozone Amount Determined by Transmittance Measurements in the Solar-Blind Ultraviolet Spectral Region
Authors: Trakhovsky Eli
Published: February 2023

Air pollution monitoring stations presently use various techniques for measuring the concentrations of O3, SO2 and NO2, namely: chemical, chemi-luminescence or absorption cell methods. But they all involve one or more of the following disadvantages: the pollutant is measured at a particular point which may not represent the prevailing conditions in the area of interest, the apparatus usually requires frequent calibration, it is bulky, non-portable and relatively expensive.
High Pressure CO2 Laser Output Implications in Infrared Dial
Authors: Kusters J.K. , Rye B.J. , van Dijk J.W.
Published: February 2023

DIAL measurements are made in the face of a number of sources of bias and noise arising within both the atmospheric system and the measurement procedure (1,2). At CO2 wavelengths the use of a fully tunable laser operating typically at a pressure of 10 atmospheres has a number of apparent advantages over use of lasers at atmospheric pressure or below, especially if output can be achieved at more than one wavelength at a given time.
An Effective Frequency Technique for Laser Measurements with Finite Spectral Bandwidth
Authors: Korb C. Laurence , Weng Chi Y.
Published: February 2023

This paper describes a fundamentally new method of treating the effects of laser finite bandwidth for both integrated path and differential ranging lidar measurements of differential absorption. We show that, for laser bandwidths less than the atmospheric line width, the effects of finite bandwidth on a measurement near the center of an absorption line can be treated as due to an equivalent monochromatic measurement at an effective frequency. The method is applied to measurements in the atmosphere with various laser line shapes. The effective frequency is shown to have a simple form which is independent of the detailed atmospheric line shape. Complex laser line shapes including multi-mode spectral structure can be simply treated using this technique. The effective frequency method greatly simplifies the computation of forward problems in radiative transfer1. More importantly, it allows the inverse problem of species concentration to be solved using algebraic methods as opposed to complicated inversion techniques2.
Airborne Lidar Measurements of Atmospheric Gases and Aerosols
Authors: Browell Edward V.
Published: February 2023

The use of lasers in the remote sensing of various atmospheric parameters from aircraft platforms is becoming accepted by the atmospheric science community as an important technique for the study of large-scale chemical and meteorological phenomena. The parameters that have been measured most extensively with airborne lidar include profiles of O3, H2O, aerosols, and winds. The Differential Absorption Lidar (DIAL) technique is used in the profiling of O3 and H2O; and aerosol distributions, which contain important meteorological information on the planetary boundary layer and the free troposphere, can be obtained by a single wavelength lidar technique. When measured at multiple wavelengths, additional information on aerosol types can be obtained. Wind components along the lidar line-of-sight can be obtained by using the doppler lidar technique, and when this is combined with a scanning capability, the lidar can produce wind field maps.
Measurements of Aerosol Backscatter Phase Function and Extinction by High Spectral Resolution Lidar
Authors: Grund C.J. , Eloranta E.W.
Published: February 2023

The University of Wisconsin high spectral resolution lidar (HSRL) technique interferometrically separates the atmospheric backscattered signal into its aerosol and molecular constituents (Shipley et al., (1983), Sroga et al. (1983)). Recent improvements in the HSRL are shown schematically in Fig. 1. Most notable among the changes are: the incorporation of a CuCl2 laser transmitter, some receiver simplification and temperature stabilization, and, the installation of phototubes with very low afterpulse probability. These changes allow operating periods of up to 7 hrs before retuning, lower statistical noise, and decreased calibration uncertainty. The improvements have led to reduced time averaging requirements, while maintaining daylight and eye-safe operations.
Absorption Coefficient of Ammonia for Laser Remote Sensing of Atmospheric Trace Quantities
Authors: Hawley James G. , Powell Diane D. , Cooper David E.
Published: February 2023

Ammonia is an important atmospheric trace molecule in the atmospheric transformation of sulfur and nitrogen compounds. Because it is a base, NH3 dissolved in water droplets as the ammonium ion promotes increased solubilities of sulfate and nitrate ions. Ammonia, therefore, is suspected of playing a role in the formation of acid rain. Infrared lidars based on the CO2 laser could be used to remotely monitor ammonia concentrations in the atmosphere.
The Vertical Distribution of Marine Aerosols Inferred from Dual-wavelength Radiance Measurements
Authors: Durkee Philip A.
Published: February 2023

New visible and near-infrared radiometers on meteorological and oceanographic satellites have made it possible to detect variations of aerosol particles within the marine atmospheric boundary layer. Fett and Isaacs (1979) hypothesized that some brightness variations observed in DMSP (Defense Meteorological Satellite Program) images of cloud-free ocean regions were caused by variations of particle concentrations. Hindman, et al. (1984) and Durkee (1984) have varified through field studies that satellite-detected brightness variations observed in AVHRR (Advanced Very High Resolution Radiometer) and CZCS (Coastal Zone Color Scanner) images are related to measured variations of aerosol particles within the marine boundary layer. Further, Isaacs (1980) and Durkee (1984) have shown that variations of marine atmospheric boundary layer properties such as relative humidity and inversion height are related to particle concentrations and thus aerosol optical depth. Therefor, satellite-detected brightness variations can be related to variations of boundary layer properties under certain meteorological conditions.
The UARS Microwave Limb Sounder Experiment
Authors: Waters J.W. , Barath F.T. , Burke J.R. , Chavez M.C. , Cofield R.E. , Curtis P.D. , Flower D.A. , Fraschetti T.C. , Frerking M.A. , Froidevaux L. , Hardy J.C. , Harris W.M. , Harwood R.S. , Holden J.R. , Jarnot R.F. , Lahoz W.A. , Lau C.L. , Lau G.K. , Lemaster C.A. , Loo M.S. , Maddison B.F. , Matheson D.N. , Natzic M.J. , Oliver M.B. , Parker D.J. , Peckham G.E. , Perun V.S. , Pickett H.M. , Read W.G. , Soltis F.S. , Suttie R.A. , Tarsala J.A. , Voge C.C. , Wilson W.J.
Published: February 2023

The UARS Microwave Limb Sounder (MLS) measures ClO (~25-45 km), O3 (~15-80 km), H2O (~15-85 km), and pressure (~30-60 km). ClO is the dominant form of chlorine which destroys ozone in the stratosphere; its measurement on a global scale, which will be done by the MLS, is essential for understanding and monitoring the depletion of stratospheric ozone by chlorine from industrial products. Simultaneous measurements of O3 and H2O provide additional important information on stratospheric ozone chemistry. The H2O and O3 measurements will be to higher altitudes than previously explored on a global basis. The pressure measurements provide the vertical reference for composition measurements. Secondary MLS measurement goals include H2O2, HNO3, temperature, and one component of wind in the mesosphere. Measurements are made by observing millimeter-wavelength spectral line thermal emission as the instrument field-of- view is vertically scanned through the atmospheric limb. All are made simultaneously and continuously, at all times of day and night. Prior development for the UARS MLS included an aircraft [1,2] and balloon [3,4,5] MLS. Development has also started on an MLS experiment for the future Earth observing system (Eos); the Eos MLS is described in a separate paper presented at this meeting.
Atmospheric Remote Sensing with SCIAMACHY
Authors: Burrows J.P. , Schneider W. , Geary J.C. , Chance K.V. , Goede A.P.H. , Aarts H.J.M. , de Vries J. , Smorenburg C. , Visser H.
Published: February 2023

SCIAMACHY is an atmospheric remote sensing satellite instrument. It is a passive instrument whose primary measurement objective is to observe the absorptions of tropospheric and stratospheric trace gases in the solar spectrum. Two identical telescope-spectrographs (TS1 and TS2) will observe transmitted, reflected, and scattered light from the atmosphere in the UV, visible and near-infrared wavelength regions (200 - 2400 nm). There are two primary modes of data collection: simultaneous 1 limb and nadir viewing, and solar/lunar occultation. The limb scan yields a vertical profile of atmospheric scattered light, whereas the scan across the satellite track in nadir viewing yields global coverage of the reflected and scattered light penetrating down to the earth's surface or to cloud top. When in view the occultation of the sun or moon will be recorded.
Atmospheric Temperature Sounding with a Multi-Order Fabry-Perot Interferometer
Authors: Wang Jinxue , Drayson S. Roland , Hays Paul B.
Published: February 2023

During the past decade considerable progress has been made in the passive IR remote sounding of the vertical temperature profiles of the atmosphere. However, most of the sounders are low spectral resolution instruments, leading to low vertical resolution. The information derived from those sounders are useful, but falls short of the requirements for numerical weather forecasting models mainly because of the insufficient vertical resolution and cloud contamination effects. The limitation in vertical resolution is caused partly by the broadness of contribution functions of the current instruments which is due partly to their low spectral resolution. When the contribution functions are broad, emitted energy reaching the sounder in each channel will have components originating from a thick layer of the atmosphere, making reconstruction of fine-scale vertical structures practically impossible. One way to decrease the width of the contribution function is to go to instruments of much higher spectral resolution, which are able to resolve the individual spectral lines. The Fabry-Perot Interferometer (FPI) is one of the instruments that can provide the high spectral resolution required.
High Resolution Atmospheric and Surface Variability from Combined Mams and Vas Radiances
Authors: Moeller Christopher C. , Menzel W. Paul , Strabala Kathleen I.
Published: February 2023

Measuring of the variation of atmospheric and surface quantities such as moisture and stability at small scales is an important step to monitoring, understanding and forecasting mesoscale processes. While few ground based observing systems provide the high resolution coverage with sufficient areal extent necessary to study mesoscale variation, satellite observing systems have proven to be extremely useful in this endeavor. For instance, moisture and stability products from the geostationary platform VISSR Atmospheric Sounder (VAS) exhibit interesting detail at the meso B (20-200 km) level (Chesters et al., 1986; Smith et al., 1985). However, variation at the meso C scale (2-20 km) and at the lower end of the meso B scale ( about 20-100 km) suffer from the effects of noise. Noise can be greatly reduced by using a high resolution data collection system. The Multispectral Atmospheric Mapping Sensor (MAMS), with its 100m resolution over a 36km swath, is well suited to provide high resolution mesoscale information about the atmosphere and surface of the earth. A more complete depiction of the atmospheric state at the smaller scales is possible through the combination of the high horizontal resolution MAMS data with the vertical sounding data of the VAS.
Cirrus Cloud Velocity-Backscatter Correlations and Instrument Spatial Resolution Effects on Remote Wind Sounding Errors
Authors: Grund C.J , Weinman J.A. , Eloranta E.W.
Published: February 2023

Optical remote sensing techniques for the space-based determination of wind fields over the poorly monitored oceans and southern hemisphere land areas hold great promise for lengthening forecast times from numerical weather prediction models. Real-time wind sheer profiles can potentially be used to enhance aircraft and space-launch operations safety. Doppler lidar has been identified1 as a front runner for near term space deployment as a tropospheric/stratospheric wind sensor.
Detector Channeling Hypothesis for Enhanced Structure Observed in CLAES System Blocker Filter Functions
Authors: Kumer J. B. , Mergenthaler J. L. , Janies T. C. , Roche A. E. , Sterritt L. W. , Potter J. F.
Published: February 2023

The Cryogenic Limb Array Etalon Spectrometer (CLAES) will derive Stratospheric temperatures and constituent number densities from the measurement of infrared spectral emissions, during its 18 month mission on board the NASA Upper Atmosphere Research Satellite (UARS). Overviews of the CLAES experiment and hardware are given by Roche et al (Ref 1) and Burriesci et al. (Ref 2). In this paper we describe a detector channeling hypothesis for enhanced structure (Ref 3) observed in system filter functions retrieved from CLAES spectral calibration data (Ref 4).
Radiometric Calibration of the Cryogenic Limb Array Etalon Spectrometer (CLAES) on UARS
Authors: Sterritt L. W. , James T. C. , Kumer J. B. , Roche A. E. , Steakley B. C. , Zickuhr K. M.
Published: February 2023

The Cryogenic Limb Array Etalon Spectrometer (CLAES) will derive stratospheric temperatures and constituent number densities from the measurement of infrared spectral emissions, during its 18 month mission on board the NASA Upper Atmosphere Research Satellite (UARS). An experiment overview of the Cryogenic Limb Array Etalon Spectrometer (CLAES) is given by Roche and Kumer (ref. 1); an instrument overview is given by Burriesci, Naes, Springer, and Steakley (ref.2). This paper addresses the radiometric calibration of the CLAES. An extended area full aperture blackbody simulator (graybody) mounted on the instrument aperture door has been used for laboratory calibration, and will be used for repeated calibrations in orbit. The advantages of full aperture calibration sources are well understood; complete end-to-end calibration is provided, and the calibration accuracy is not limited by uncertainty in knowledge of the source position. The CLAES calibration source (fig. 1) is a 22.15 cm diameter anodized aluminum plate with concentric circular "γ" grooves to provide enhanced emissivity. The source is mounted on the CLAES aperture door with 4 fiberglass insulating supports. The perimeter and back of the calibration source are enclosed in an aluminum shield containing multilayer insulation (MLI). For laboratory calibration the source is heated with strips of heating "tape" on the back face. In orbit the source will be heated "passively" while the door is open, by exposure to radiation from the earth. Calibration source temperature is measured with an array of platinum resistance thermometers on the rear face of the source. During calibration intervals, the door will be closed and calibration data will be obtained over a range of temperature as the source cools to the internal radiative ambient of the cryogenic telescope (baffle temperature ≈ 130K). CLAES calibration goals for accuracy and precision are ≈3%; of particular concern is stability (repeatability) of the calibration source over a nominal 1.5 year mission. The primary sources of uncertainty in the instrument calibration are the knowledge of the source apparent emissivity, Δϵ, the thermometry error, ΔT, the uncertainty in wavelength to which the instrument is tuned, Δλ, and the uncertainty of the instruments spectral bandpass, Δδe. These items will be discussed below.
Far-Infrared Remote Sensing from Balloon Platforms
Authors: Carli B.
Published: February 2023

Far-infrared emission spectroscopy from a balloon platform allows the observations of several atmospheric constituents. The most recent results include ClO, OH and HBr.
Application of the Optimal Probability Method to the Retrieval of Temperature, Water Vapor and Ozone Profiles
Authors: Clough S.A. , Isaacs R.G. , Worsham R.D. , Moncet J.L.
Published: February 2023

A code has been developed to perform the retrieval of atmospheric state parameters using the method of nonlinear least squares in conjunction with a program to compute the forward problem (Isaacs, 1988). In the present study, FASCODE (Clough et al., 1986) has been utilized for the forward problem other algorithms including rapid algorithms may readily be accommodated. The method has been applied to retrievals of temperature profiles, surface temperature and pressure, water vapor profiles and other constituent distributions using both real and simulated data. The method is applicable to both sequential and simultaneous retrievals. Either of two approaches may be selected for performing retrievals: the method of ridge regression or the maximum likelihood method. Our implementation of the latter approach is similar to that discussed by Rodgers (1976, 1987) and more recently by Eyre (1989).
Recent Lidar Developments to Monitor the Structure and Dynamics of Middle Atmosphere
Authors: Chanin M.L.
Published: February 2023

The recent years have demonstrated the major role that lidars can play in the description and understanding of the dynamics of the middle atmosphere. This concerns mainly the region where the radars are blind (25-70 km) and which has been mostly described by rocket techniques.
Calibration Sensitivity of Atmospheric Scattering Properties Measured with an Incoherent Doppler Lidar
Authors: Sroga J.T.
Published: February 2023

Monte Carlo simulations have been used to estimate the instrument calibration sensitivity of aerosol scattering properties measured with an incoherent Doppler lidar at λ=532nm.
Nonlinear Remote Sensing Opportunities in the Atmosphere
Authors: Palmer A. Jay
Published: February 2023

Nonlinear interactions of radiation with the atmosphere have been of interest to the scientific community for some time now, primarily in connection with nonlinear propagation phenomena such as self-focusing, thermal blooming, and stimulated scattering1. The nonlinear interaction of radiation with atmospheric aerosols, including such interesting applications as dispersal of fogs and hazes has also been thoroughly treated2. These processes are all examples of nonlinear interactions strong enough to significantly alter either the real or imaginary part the propagation vector of the radiation. The high radiation fluences required for these processes limits their occurrence in the atmosphere to short ranges or requires the use of very high energy beams.
Overview of the Network for the Detection of Stratospheric Change
Authors: Kurylo M. J.
Published: February 2023

An update will be given of the current status of the instrument development and implementation of this new ground-based remote sensing research and monitoring network.
ECC Ozonesonde and Dobson Umkehr Observations During STOIC 1989
Authors: Komhyr W. D. , Lathrop J. A. , Opperman D. P.
Published: February 2023

Ten electrochemical concentration cell (ECC) ozonesondes were successfully flown at the Jet Propulsion Laboratory’s Table Mountain Facility during the Stratospheric Ozone Intercomparison Campaign (STOIC) conducted July 19 to August 2, 1989. Umkehr observations were made with a Dobson spectrophotometer during most mornings and afternoons. Ozone measurements were conducted primarily to assess the performance of lidar and microwave instrumentation destined for use in the planned station Network for Detection of Stratospheric Change (NDSC). Because the lidar and microwave are remote ozone measurement techniques, it was of interest to compare data obtained with these instruments with data from balloon-borne ECC ozonesondes that measure ozone directly by counting ozone molecules during balloon ascent. While most of the balloon soundings reached altitudes of 30-34 km, ozone measurements to about 39 km were obtained for two of the soundings.
Sulfur Dioxide Absorption Cross-Section Measurements Between 265 and 298 Nanometers
Authors: Weitkamp Claus , Thomsen Olaf , Bisling Peter
Published: February 2023

The wavelength region between 265 and 315 nm is characterized by negligible optical absorption of the major atmospheric gases. Only ozone and sulfur dioxide show strong absorption in this wavelength range. Whereas the Hartley band of ozone which peaks at 255 nm is dominated by a broad hump with little structure resolved under atmospheric conditions, the SO2 spectrum with its maximum around 285 nm shows well-separated peaks 1 to 2 nm apart with cross-section ratios > 5 between some peaks and adjacent valleys.
Optical Scintillation Instruments for Measuring Heat and Momentum Fluxes in the Atmospheric Surface Layer
Authors: Hill Reginald J. , Ochs Gerard R.
Published: February 2023

Experimental validation against in-situ instruments shows that optical scintillation techniques are very promising for measuring the atmospheric surface-layer fluxes of heat, momentum, and stability.
Cloud Microphysics Retrieved From Reflected Solar Radiation Measurements
Authors: Nakajima Teruyuki , King Michael D.
Published: February 2023

Clouds have a large contribution to the earth's radiation budget (Ramanathan et al., 1989). Changes of cloud optical thickness and droplet size will bring a large climatic change (Liou and Ou, 1989). A cooling effect due to increasing cloud albedo with increasing anthropogenic cloud condensation nuclei may be comparable with the earth's warming due to CO2 increase (Twomey et al., 1984; Wigley, 1989; Radke et al., 1989). Therefore it is very important to study the cloud optical characteristics. In this paper we present results from our retrieval of the cloud optical thickness and effective droplet radius of marine stratocumulus clouds observed in the Marine Stratocumulus Intensive Field Observation (IFO), which is one component of the First ISCCP Regional Experiment (FIRE) (Albrecht et al., 1988).
Recent Infrared Emission Measurements of Predawn N2O5 Over New Mexico
Authors: Blatherwick R.D. , Murcray F.H. , Murcray F.J. , Murcray D.G. , Vanasse G.A. , Hoke M.
Published: February 2023

Data obtained with the AFGL SCRIBE system (Stratospheric CRyogenic Interferometer Balloon Experiment) during a balloon flight in July, 1984 were recently used to perform the first post-dawn morning measurement of N2O5 [1].
Retrieval of Monthly Precipitation over Land and Ocean with Polarization Corrected SSM/I Data Using Probability Distribution Functions
Authors: Weng Fuzhong , Vonder Haar Thomas H.
Published: February 2023

The precipitation measurements have been of wide interests ranging from the agriculture to the water supply. The role of latent heat released from precipitation in the atmospheric dynamics and general circulation has intensified the rainfall measurements. Due to the sparse measurements by the conventional stations and the inaccuracy associated with them, the requirement for the global measurements of precipitation will be melt with the satellite remote sensing techniques.
A Technique to Infer the Heating Rate Associated With Non-LTE Processes in Upper Mesospheric and Lower Thermospheric Ozone
Authors: Mlynczak M. G.
Published: February 2023

Non-LTE processes in ozone are significant components of the energy budget of the upper mesosphere and lower thermosphere [Mlynczak, 1991]. The exothermic recombination reaction that forms ozone and the upwelling radiation (from the vicinity of the stratopause) absorbed by ozone have the potential to heat the mesopause region (80-105 km) at rates exceeding 6K/day if all potential (radiative plus chemical) energy would be converted to heat. Calculation of the heating rate requires a detailed knowledge of the processes by which ozone exchanges internal energy with its environment through chemical, collisional, and radiative processes. At present, the knowledge of the rate coefficients describing the non-LTE processes is probably not sufficient to permit reliable calculations of the heating associated with non-LTE processes in ozone. Shown in Fig. 1 are the heating rates (in K day-l) calculated using two different models of non-LTE processes in ozone. The curve labeled "1" is the heating rate calculated using the model of Solomon et al. [1986] and the curve labeled "2" is the heating rate calculated using a model from Mlynczak and Dray son [1990a]. The two non-LTE models differ significantly in their parameterization of the non-LTE processes in ozone. In this paper, a technique whereby the heating rate may be inferred from appropriate measurements from satellite remote sensing instruments will be examined. This technique allows for the inference of the heating rate virtually independent of assumed kinetics models.
High-Resolution Spectroscopy of Spectral Lineshapes
Authors: Duggan P. , Drummond J.R. , Forsman J.W. , Sinclair P.M. , May A.D.
Published: February 2023

Remote sensing can be described as an analysis of the state of an atmosphere (composition, temperature, etc) from an examination of the radiance exiting the atmosphere. In order to correctly perform such an analysis or "retrieval" of physical parameters, it is essential to have good spectroscopic data.
A New High Pulse Repetition Frequency, Multiple Wavelength, Differential Absorption CO2 Lidar System for Atmospheric Trace Gas Measurements
Authors: Ben-David Avishai , Emery Silvio L. , Gotoff Steven W. , D’Amico Francis
Published: February 2023

A multiple wavelength, pulsed CO2 lidar system that operates at a pulse repetition frequency (PRF) up to 200 Hz (for a single wavelength) and permits the random selection of CO2 laser wavelengths for each laser pulse is presented. The CO2 laser was developed by Laser Science Incorporated, Cambridge, Massachusetts. The lidar system is employed to measure atmospheric transmission using laser pulse bursts consisting of groups of 10 different wavelengths (the maximum available is 16 wavelengths) at a repetition rate of up to 3 Hz (the maximum available is 12 Hz) and at a PRF of 150 Hz for wavelengths within a burst. The, tuning mechanism for switching wavelengths utilizes a stationary grating and a flat mirror controlled by a galvanometer. The laser is able to transmit up to 100 mJ per pulse.
NOAA Multi-wavelength Lidar Observations of Stratospheric Aerosols Over Boulder, Colorado
Authors: Grund Christian J. , Post Madison J. , Langford Andrew W.
Published: February 2023

Three lidar systems maintained by the National Oceanic and Atmospheric Administration's (NOAA) Environmental Research Laboratories in Boulder, Colorado, have been used to observe the stratospheric aerosol from the Mt. Pinatubo eruption. The Wave Propagation Laboratory (WPL) operates two of these systems: a CO2 Doppler lidar employing coherent detection operating at 10.59 μm [Post and Cupp, 1990], and a ruby lidar operating at 0.695 μm [Eberhard and McNice, 1986]. The Aeronomy Laboratory (AL) operates an ozone DIAL system employing a Nd:YAG-pumped dye laser that can be configured to measure aerosol and molecular backscatter at 0.610, 0.537, 0.532, or 0.305 μm [Profitt and Langford, 1991]. The ruby lidar is located on the National Institute for Science and Technology complex in Boulder, Colorado. The CO2 system is located on table mountain 17 km north of the ruby lidar, and the AL lidar is located on Fritz peak, 35 km southwest of the ruby system.
Pinatubo Cloud Over Garmisch-Partenkirchen
Authors: Jäger H.
Published: February 2023

The explosive eruptions of the Philippine volcano Pinatubo in mid-June 1991 caused the first major perturbation of the stratosphere since the eruption of the Mexican volcano El Chichón in April 1982. Early groundbased, satelliteborne and in situ observations of the Pinatubo eruption cloud were collected by McClelland et al., 1991. Satellite images from July and August did not show a significant transport of volcanic debris to mid-latitudes, the major part of the cloud was reported to be confined in an equatorial band 15°S to 25°N with the densest part in the 20 to 25 km height range and further layers below 20 km.
Cirrus particle scattering profiling: Validity assessment of the Klett solution with combined lidar measurements
Authors: Ansmann Albert , Riebesell Maren , Wandinger Ulla , Weitkamp Claus , Michaelis Walfried
Published: February 2023

The height profiles of the aerosol extinction coefficient (from the nitrogen or oxygen Raman signal profile, Ref. 1) and the aerosol backscatter coefficient (from the elastic-backscatter- to-Raman signal ratio, Ref. 2) can be determined independently from each other using a combined Raman elastic-backscatter lidar. The systematic and statistical errors are smaller than 20 % in regions of strong particle scattering such as the boundary layer or clouds (Ref. 3). Therefore a combined lidar allows the validation of solutions for the extinction and backscatter coefficients obtained with the Klett method (Ref. 4) from the elastic backscatter signal alone.