A differential absorption and scattering lidar that measures hydrogen chloride with a sensitivity of
NASA Technical Reports Server (NTRS)
Recently measured properties of water vapor (H2O) absorption lines have been used in calculations to
The basic parameters (range, signal-to-noise ratio, and sensitivity) of a lidar using NH3 and CO2 lasers are calculated. The principle of lidar operation is based on the differential absorption recording. Absorption spectra of all known Freons are considered in the spectral range 9-13.5 ?m and ...
NASA Astrophysics Data System (ADS)
profiles obtained by differential absorption lidar (DIAL) analysis. ... Differential absorption lidars (DIAL) have been and continue to be widely used for the ...
NASA Website
The design and operation of a differential absorption lidar system capable of remotely measuring the
A ground-based differential absorption lidar (DIAL) system is described which has been developed for
A parametric analysis of the Shuttle-borne differential absorption lidar concept for the measurement
Many studies recently have investigated the active remote sensing of atmospheric greenhouse gases, such as CO2 and CH4, by means of differential absorption lidar systems. According to them, the accuracy of the laser wavelengths used is one of the most important issues of this technique in terms of conformance to the high measurement ...
A brief survey is given of remote measurements of air pollutants by the differential absorption technique. The use of differential absorption lidar (DIAL) systems in pollution studies is discussed, and suitable lasers are identified. Some results are presented for DIAL measurements with a tunable CO2 laser of the water vapor ...
... Title : NONLINEAR RESONANT ABSORPTION EFFECTS ON THE DESIGN OF RESONANCE FLUORESCENCE LIDARS AND LASER GUIDE ...
DTIC Science & Technology
Polarization-sensitive lidars have proven to be highly effective in discriminating between spherical
The ambient atmosphere between the laser transmitter and the target can affect CO{sub 2} differential absorption lidar (DIAL) measurement sensitivity through a number of different processes. In this work, we will address two of the sources of atmospheric interference with CO{sub 2} DIAL measurements: effects due to beam propagation ...
DOE Information Bridge
The University of Wisconsin high spectral resolution lidar (HSRL) measures optical properties of the
A small compact ozone differential absorption lidar capable of being deployed on a small aircraft or
Development of advanced differential absorption lidar (DIAL) receivers is very important to increase
The theory of differential absorption lidar measurements for lines with a Voigt profile is given and
Page 1. i Modeling Multiple Scattering and Absorption for a Differential Absorption LIDAR System by Daniel D. Blevins BS ...
The basic parameters (range, signal-to-noise ratio, and sensitivity) of a lidar using NH{sub 3} and CO{sub 2} lasers are calculated. The principle of lidar operation is based on the differential absorption recording. Absorption spectra of all known Freons are considered in the spectral range ...
Energy Citations Database
The characteristics of the lidar reflectance of the Earth's surface is an important issue for the IPDA lidar technique (integrated path differential absorption lidar) which is the proposed method for the spaceborne measurement of atmospheric carbon dioxide within the framework of ESA's A-SCOPE project. Both, the ...
We present a new differential absorption lidar (DIAL) method for atmospheric trace SO2 using multiwavelength curve fitting. With this method we use five wavelengths around a SO2 absorption peak and obtain SO2 and O3 concentrations by fitting their absorption cross sections to measured DIAL and null results. A SO2 ...
A CW tunable 10.6 microm CO(2) laser differential absorption lidar (DIAL) system has been developed, for the first time to our knowledge, for the remote sensing of triacetone triperoxide (TATP) gas vapors, which have strong absorption lines at several wavelengths, including 3.3, 8.3, and 10.6 microm. The DIAL laser beam was transmitted ...
PubMed
Lidar monitoring of the gaseous molecules in atmosphere can be used for concentration measurements of the toxic pollutants in air of the urban and industrial regions. Such a concentration study in the multi-components gaseous mixture by lidar technique is a complex problem in atmospheric pollution monitoring. The differential ...
Direct Detect Doppler wind lidar retrieves the three dimensional wind by discriminating the frequency shift of the atmosphere elastic backscatter signal. The wind measurement sensitivity of edge detect technology based on iodine absorption lines highly depends on the aerosol backscatter ratio indicating the mixing ratio of aerosol to ...
Measurement Description: The UV Differential Absorption Lidar (DIAL) system is used to measure aerosol, cloud, and ozone profiles above the aircraft [Browell ...
Airborne UV Differential Absorption Lidar (DIAL): Measuring Ozone and Aerosols in the Atmosphere. Figure 1: The Electromagnetic Spectrum The ozone hole ...
Sep 9, 2011 ... DIAL Ops. The NASA Langley airborne Differential Absorption Lidar (DIAL) uses ultraviolet (UV) DIAL wavelengths of 288 and 300 nm for the ...
Computer hardware and software of the NASA multipurpose differential absorption lidar (DIAL) sysatem
The depolarization of backscatter from ice particles at the CO[sub 2] lidar wavelength of 10.59 [mu]m was investigated through field measurements, with simultanous depolarization measurements taken at 0.6943 [mu]m for comparison. The depolarization ratio at the infrared wavelength was usually at or below the lidar's ...
Mobile differential absorption lidar (DIAL) systems have been used for the last two decades. The lidar group in Lund has performed many DIAL measurements with a mobile lidar system which was first described in 1987. This report describes how that system w...
National Technical Information Service (NTIS)
This study is carried out system error evaluation of an incoherent wind Doppler LIDAR system that uses an iodine filter. Sharp slopes of an iodine filter provide better wind-measuring sensitivity than a Fabry-Perot etalon. The magnitude and sign of the Doppler shift are obtained from the ratio of the intensities of two signals arising from two slopes of an ...
A differential absorption lidar has been built to measure CO2 concentration in the atmosphere. The transmitter is a pulsed single-frequency Ho:Tm:YLF laser at a 2.05-microm wavelength. A coherent heterodyne receiver was used to achieve sensitive detection, with the additional capability for wind profiling by a Doppler technique. Signal ...
The GSFC pressure-temperature lidar is a differential absorption lidar operating in the oxygen A band absorption region (760 to 770 nm), and utilizes two tunable pulsed alexandrite lasers. For obtaining temperature measurements with an accuracy of less th...
We introduce a new approach to coherent lidar range-Doppler sensing by utilizing random-noise illuminating waveforms and a quantum-optical, parallel sensor based on spatial-spectral holography (SSH) in a cryogenically cooled inhomogeneously broadened absorber (IBA) crystal. Interference between a reference signal and the lidar return in the spectrally ...
including phytoplankton carbon biomass and physiology ... Characterization of algal absorption spectra, since physiology is best ...
Comparative study is performed for a mid-infrared differential absorption lidar system with different wavelengths around 1.6 �m and 2 �m for remote sensing of green-house effect gas CO2. Simulation based on lidar equations is performed for estimating detectable range and detectable concentration per unit volume. Different ...
Incoherent Doppler wind lidar measures the wind by detecting the frequency shift of the laser backscattering from aerosol and atmosphere molecules. The wind measurement sensitivity of edge detection technology like iodine vapor filter depends on the aerosol load of probe volume. The current Direct detect wind lidar system has to obtain ...
The proposed effort extends the micro-lidar technology to compact tunable transmitters suitable for measurements of H2O vapor by Differential Absorption ...
We have developed a lidar technique for measuring the tropospheric C02 concentrations as a candidate
Airborne Differential Absorption Lidar (DIAL) Field Experiment Examples: Example Aerosol, Ozone, and Water Vapor Images ...
... range and chem-bio agent detection limits of direct detection LWIR differential absorption LIDAR systems * Standoff range: ~ 2x increase for fixed ...
Aug 4, 2011 ... In the DIAL technique, the gas concentration profile is determined by analyzing the lidar backscatter signals for laser wavelengths tuned ...
Mar 29, 2011 ... Tom McGee, Don Silbert. -Combines Rayleigh Lidar, Differential Absorption Lidar (DIAL), and Raman DIAL -Zenith viewing ...
DISSERTATIONS. 6. A High Spectral Resolution. Lidar Based on. Absorption. Filter . Paivi Piironen. ACADEMIC. DISSERTATION. To be present, with the permission ...
� , due to uncertainties in the ozone absorption cross-section; .... in ozone absorption cross-section, and imperfection of the dead-time and SIB ...
The CO2 differential absorption lidar (DIAL) technique have advantages such as high vertical and horizontal resolution, the ability to acquire simultaneous species and aerosol profiles, day and night coverage and no dependence on external radiation. An all solid-state l.5 ?m CO2 differential absorption coherent ...
The measurement sensitivity of CO{sub 2} differential absorption lidar (DIAL) can be affected by a number of different processes. The authors have previously developed a Huygens-Fresnel wave optics propagation code to simulate the effects of two of these processes: effects caused by beam propagation through atmospheric optical ...
Sep 3, 2010 ... RESEARCH SUBTOPIC TITLE: Lidar, Radar, and Passive Microwave. PROPOSAL TITLE: High Sensitivity, Radiation Hard InGaAs LIDAR Receiver for ...
Methane is the third most important greenhouse gas in the atmosphere after water vapour and carbon dioxide. A major handicap to quantify the emissions at the Earth's surface in order to better understand biosphere-atmosphere exchange processes and potential climate feedbacks is the lack of accurate and global observations of methane. Space-based integrated path differential ...
LiDAR (Light Detection and Ranging) can be used as a ranging system using electromagnetic waves in the optical domain. LiDAR airborne or satellite sensors are promising techniques for river bathymetry and water surface altimetry considering its potential accuracy, its high spatial density and resolution. When considering physics of ...
We present preliminary experimental results, sensitivity measurements and discuss our new CO2 lidar system under development. The system is employing an erbium-doped fiber amplifier (EDFA), superluminescent light emitting diode (SLED) as a source and our previously developed Fabry-Perot interferometer subsystem as a detector part. Global measurement of ...
Remote detection of chemicals using LIDAR (Light Detection and Ranging) utilizing DIAL (Differential Absorption LIDAR) is now a standard detection technique for both military and civilian activities. We have developed a novel nonlinear optical phase conju...
This report describes the background theory, experimental techniques, and results of research relating to lidar polarization, scattering, and absorption effects using the GL/OP low altitude lidar system. The work, which is aimed at improving the understan...
This paper presents cirrus cloud observations made with the High Spectral Resolution Lidar (HSRL) and the Volume Imaging Lidar (VIL). The HSRL was redesigned to use an iodine absorption filter in place of the Fabry-Perot etalon that was used for spectral ...
A case study is presented of 6.5 h of simultaneous colocated stratospheric Differential Absorption Lidar (DIAL) measurements of ozone concentration and Rayleigh-Mie Doppler (RD) lidar measurements of horizontal wind velocity from the Observatoire de Haute...
The Lidar Atmospheric Sensing Experiment (LASE) Instrument is the first fully-engineered, autonomous Differential Absorption Lidar (DIAL) System for the measurement of water vapor in the troposphere (aerosol and cloud measurements are included). LASE uses...
Active remote sensing using lidar shows high potential for the measurement of atmospheric greenhouse gases like carbon dioxide or methane from spaceborne platforms. Due to the weak atmospheric backscatter in the near IR the IPDA lidar (Integrating Path Differential Absorption Lidar) technique is preferred over the ...
Backscatter absorption gas imaging (BAGI) is a technique that uses infrared active imaging to generate real-time video imagery of gas plumes. We describe a method that employs imaging at two wavelengths (absorbed and not absorbed by the gas to be detected) to allow wavelength-differential BAGI. From the frames collected at each wavelength, an absorbance image is created that ...
The present volume on lidar for remote sensing discusses lidar system techniques for remote sensing of atmospheric pollution, airborne and surface-based lidar for environmental sensing of water and oceans, Doppler lidar for wind sensing and related measurement, aerosol measurements using lidar, ...
Differential absorption lidar and Raman lidar have been applied to the range-resolved measurements of water vapor density for more than 20 years. During this period, there have been considerable advances in laser and lidar technology, as well as in the understanding of the factors required to optimize both ...
Experiments with a blue-green laser radar system were conducted off the coasts of Ireland and Scotland in June, 1999. The purpose of this test was to measure the effect of the water optical properties on the polarization state and decay rate of the lidar return signal. The lidar system, the K-meter Survey System (KSS), was configured to transmit linearly ...
The development of eye-safe, solid-state Lidar systems is discussed, with an emphasis on Coherent Doppler Lidar for Atmospheric Wind Measurements. The following subject areas are covered: tunable Ho DIAL (Differential Absorption Lidar)/lidar atmospheric m...
A measurement of ambient nitrogen dioxide concentration by an air quality monitoring station, and a visible lidar system using a differential absorption lidar (DIAL) technique are performed. The agreement between measured values is within experimental error of the lidar results for average wind speeds of less than ...
The design and preliminary tests of an automated differential absorption lidar (DIAL) that profiles water vapor in the lower troposphere are presented. The instrument, named CODI (for compact DIAL), has been developed to be eye safe, low cost, weatherproof, and portable. The lidar design and its unattended operation are described. ...
We have developed a lidar technique for measuring atmospheric CO2 concentrations as a candidate for NASA�s ASCENDS mission. It uses pulsed laser transmitters to simultaneously measure a CO2 absorption line in the 1570 nm band, O2 extinction in the Oxygen A-band and surface height and backscatter. The lidar measures the energy and ...
Differential Absorption Lidar (DIAL) Investigators: Edward Browell (PI), Johnathan Hair (Co-PI), Syed Ismail
E-print Network
A near infrared differential absorption lidar technique is developed using atmospheric oxygen as a tracer for high resolution vertical profiles of pressure and temperature with high accuracy. Solid-state tunable lasers and high-resolution spectrum analyze...
We are seeking to develop a reliable methodology for multi-chemical detection and discrimination based upon multi-wavelength differential absorption lidar measurements. In this paper, we summarize some preliminary results of our efforts to devise suitable...
Aircraft in situ and Raman lidar profiles of aerosol light extinction (?ep) and 180� backscattering (?p) are compared for 6 days during the Indian Ocean Experiment (INDOEX). The measurements of ?ep and ?p were made from the National Center for Atmospheric Research C-130 aircraft using two integrating nephelometers to measure light scattering and one Radiance Research ...
... This is done by propagating a known output signal, and measuring ... optical signal will attenuate exponentially because of absorption and scattering. ...
The system control and signal conditioning electronics of the NASA three laser airborne differential
Jan 22, 2011 ... dc.title, Infrared Lidar Sensitivity to Cloud Optical and Geometrical Properties : Impluications for Earth-Orbiting Doppler Lidar, en_US ...
Line of sight velocity and measurement position sensitivity analyses for an orbiting coherent Doppler lidar are developed and applied to two lidars, one with a nadir angle of 30 deg. in a 300 km altitude, 58 deg. inclination orbit and the second for a 45 ...
A differential absorption lidar based on a tunable TEA CO2 laser emitting at 42 lines of the 'hot' 0111 � 1110 band in the range from 10.9 to 11.4 ?m is developed for detecting natural gas leakages from oil pipelines by measuring the ethane content in the atmosphere. The ethane detection sensitivity is 0.9 ppm km. The presence of ...
Remote measurements of atmospheric trace gases are critical to the understanding of both Earth and planetary meteorological systems. The conventional lidar technique currently applied is Differential Absorption lidar (DIAL). A potentially more sensitive method is Frequency Modulation (FM) spectroscopy. An original ...
A differential absorption lidar based on a tunable TEA CO{sub 2} laser emitting at 42 lines of the 'hot' 01{sup 1}1 - 11{sup 1}0 band in the range from 10.9 to 11.4 {mu}m is developed for detecting natural gas leakages from oil pipelines by measuring the ethane content in the atmosphere. The ethane detection ...
We present a new method to measure the spectral absorption properties of aerosol layers. Combined airborne spectral measurements of irradiance and actinic flux density can be employed to estimate the spectral mean absorption coefficient of an atmospheric layer. If extinction measurements, e.g. from a LIDAR, are also available, then the ...
Both lasers are pulsed at a absorption ... CO2 absorption profiles to 5 km, and relative errors of 1% at. <7 km height. ...
The measurement sensitivity of CO{sub 2} differential absorption LIDAR (DIAL) can be affected by a number of different processes. The authors address the interaction of two of these processes: effects due to beam propagation through atmospheric turbulence and effects due to reflective speckle. Atmospheric turbulence affects the beam ...
... planning, national and international politics, and ... Tactical decision aid, Sensitivity, Lidar. ... DATA SYSTEMS, *DECISION AIDS, *SENSITIVITY, HIGH ...
Until now monostatic type lidar systems have been mainly utilized in the field of lidar measurements of the atmosphere. We propose here a range-resolved bistatic lidar system using a high-sensitive cooled charge coupled device (CCD) camera. This system ha...
Active remote sensing using lidar appears to be very attractive for the measurement of atmospheric greenhouse gases like carbon dioxide from spaceborne platforms. Feasibility studies are currently being performed to demonstrate the required measurement performance. Due to the high precision required (less than 0.3 %) for climate studies, space-borne IPDA (Integrating Path ...
With atmospheric carbon dioxide concentrations rising steadily, investigations into locations and magnitudes of the sources, sinks and net surface fluxes are of increasing importance. Active space-borne measurement systems such as LIDAR offer one potential technique to derive global, near-surface concentrations. However, significant instrumental challenges need to be overcome ...
This paper presents an evaluation of the random and systematic error sources associated with differential absorption lidar (DIAL) measurements of tropospheric water vapor (H(2)O) profiles from airborne and spaceborne platforms. The results of this analysis are used in the development and performance evaluation of the Lidar Atmospheric ...
The measurement sensitivity of CO{sub 2} differential absorption lidar (DIAL) can be affected by a number of different processes. We have previously developed a Huygens-Fresnel wave optics propagation code to simulate the effects of two of these process: effects caused by beam propagation through atmospheric optical turbulence and ...
... PL-TR-91-2074 AIRCRAFT LIDAR SENSITIVITY STUDY FOR MEASURING WATER VAPOR R. J. Rieder 0. Shepherd ... Aircraft Water Vapor 32 ...
This dissertation investigates the feasibility of a novel, low power miniature lidar intended to measure the vertical distribution of atmospheric water vapor on Mars. This instrument could provide valuable information crucial to understanding the past and present climate of Mars. The emphasis is to develop a compact, efficient, all-semiconductor laser transmitter and ...
An extension of the Kalman-Bucy algorithm for on-line estimation of multimaterial path-integrated concentration from multiwavelength differential absorption lidar time series data is presented in which the system model covariance is adaptively estimated from the input data. Performance of the filter is compared with that of a nonadaptive Kalman-Bucy filter ...
In this study, we perform wind observation in the lower troposphere using the incoherent Doppler wind lidar that we previously developed for the upper troposphere and stratosphere. This Doppler lidar uses both slopes of the iodine absorption spectrum, and the Doppler shift is obtained from the ratio of the two transmission signals. ...
... the relationship between th extinction coefficient and the backscatter coefficient. Data were generated with known extinction coefficients and known ...
integrated total cross section for the Raman backscat- .... Conversion of Frequency Shifts to. Absolute Wavelengths. Band Positions and ...
of the optical system and for a fixed pulse energy show continuous improvement in sensitivity as the telescope diameter is increased. ...
... It is seen that the influence of refractive index on the lidar backscatter to extinction ratio is most sensitive for ... 5.2 Aerosol Mass Concentrations ...
