Special Issue:
"Space-Based Lidar Winds" -
Sensors JournalGuest Editor:Dr. Wayman BakerNOAA/JCSDA
Joint Center for Satellite Data Assimilation
5200 Auth Road - Room 805B
Camp Springs, MD 20746
Tel. +1 301 763 8000 ext. 7121
E-Mail: Wayman.Baker@noaa.gov;
http://www.jcsda.noaa.gov/personnel.shtml Deadline for Paper submission: 30 June 2008
SummaryThe
measurement of the global tropospheric wind field would address one of
the key unmet observational requirements for understanding and
predicting the future state of the earth-atmosphere system. Accurate,
global tropospheric wind data are needed for several key unresolved
climate questions. For a summary, please see the article by
Baker et al. in the Bulletin of the American Meteorological Society, 1995, Volume 76, pp. 869-888.
Such data would also address one of the important sources of error in
the short - to medium- range (1-7 day) weather forecasts.
A space-based Doppler wind lidar (DWL) would provide accurate, global
tropospheric wind data for both climate studies and weather
forecasting. The objectives of the Working Group on Space-Based Lidar
Winds (hereafter referred to as Lidar Working Group) are to advocate
the earliest possible deployment of a DWL, discuss the various uses of
the data, and exchange information on the latest lidar technology
developments.
Minutes of the Lidar Working Group
meetings, held semi-annually, will be posted at this website as well as
information on future meetings.
Wayman Baker
Chairperson, Working Group on Space-Based Lidar Winds
KeywordsLidar, Wind, DWL (Doppler Wind Lidar), Laser, Earth Remote Sensing
Lidar = Light Detection and Ranging
DWL = Doppler Wind Lidar
IRAD = Internal Research and Development
TRL = Technology Readiness Level
LRRP = Laser Risk Reduction Program
IPO = Integrated Program Office
NASA = National Aeronautics and Space Administration
NOAA = National Oceanic and Atmosphere Administration
Planned Papers
Title:
"A HIGHLY EFFICIENT AIR COOLED UV LASER SOURCE FOR THE LIDAR REMOTE SENSING OF BIOLOGICAL WARFARE AGENTS"Authors: S.K.Sudheer
1, Prathibha.S
2, V.P .Mahadevan Pillai
3, V.U.Nayar
31 Photonics and Microwave Division, School of Electrical Sciences, Vellore Institute of Technology University,
Vellore- 632014, India.
2
Organic and Inorganic Chemistry Division, School of Science and
Humanities, Vellore Institute of Technology University,Vellore-632014,
Tamilnadu, India.
3 Department of Optoelectronics, University of Kerala, Kariavattom, Thiruvananthapuram-695581, Kerala, India.
# For correspondence Email: sudheersk@vit.ac.in
Abstract:
Biological warfare agents have been a threat for many years but recent
advances in biotechnology make the problem potentially more serious.
The dangers caused due to these agents must be controlled by the proper
detection in proper time. Highly reliable and accurate stand off
detection tool is necessary for the detection of biological particles.
Biological warfare agents are increasingly viewed by potential
aggressors as cost effective offensive weapons, particularly when their
potential enemies have a superior conventional capability. Biological
weapons can be dispatched through relatively easy means of delivery.
Distinguishing the biological agents from the myriad of similar
naturally occurring micro organisms in the environment makes this
application more complex. Recent progress in solid state laser
technology and nonlinear optical wavelength conversion techniques can
be utilized effectively for UV LIDAR applications to detect biological
warfare agents to achieve better flexibility and control of the
available optical power. Using such devices, one can achieve highly
accurate and resolved, measurement of the distribution for atmospheric
scattering layers and biological aerosol clouds. In the present
investigation a single diode end pumped high repetition rate, Nd:YAG
laser emitting in the Ultraviolet region is designed, fabricated and
various laser beam parameters have been characterized for
biological warfare agent detection applications. Nonlinear optical
techniques have been employed to generate higher harmonics like 355nm
and 266nm in the UV region for the above studies. The experimental
setup mainly consists of a Fiber coupled pump laser diodes (Model
FAP-81-30C-800B, Coherent Inc,USA) with a maximum output power of
30Watt at a wavelength of 807-810nm at 20oC set temperature. A second
harmonic LBO crystal cut for critical phase matching placed within the
laser resonator is provided for converting a fraction of the
fundamental beam to a second harmonic beam. A type II frequency
tripling LBO non-linear crystal (cut for critical phase matching) is
also located inside the laser resonator. The third harmonic beam and
the unconverted fundamental beam are then directed across a type I
fourth harmonic LBO crystal cut for critical phase matching where a
portion of the fundamental beam and a portion of the third harmonic
beam are converted to a fourth harmonic frequency when both fundamental
and third harmonic beams propagate through the frequency quadrupling
crystal. The resulting beams are the third harmonic(355nm) and fourth
harmonic(266nm) are then directed to a fourth harmonic separator in
which the fourth harmonic beam is separated from the fundamental beam.
Maximum average powers of 5W at 355nm and 3W at 266nm have been
measured at a repetition rate of 10KHz. Minimum pulse widths of 20ns
have been observed. The mechanism of UV LIDAR consists of
transmitting ultraviolet (UV) light and detecting the
wavelength-shifted UV fluorescence that is produced by all biological
material. The fluorescence is a relatively weak light source compared
to the elastic backscattered light from aerosol particulates for either
the transmitted IR or the UV. So the detection performance of the UVF
is significantly lower, for a given laser power, compared to the
backscatter detection performance. So accurate measurement of UV
fluorescence signal and the UV backscatter signal for biosimulants
(Bacillus globigii, an anthrax simulant; Erwinia herbicola, a
vegetative bacteria simulant; and male-specific coliphage type 2, an
infectious viral simulant) and interferents such as road dust, diesel
exhaust, burning vegetation, and smoke. The wavelengths 355nm and 266nm
are suitable for the effective detection of the above biosimulants.
Submission
Sensors (
http://www.mdpi.org/sensors/) is a highly rated journal with a 1.373 impact factor in 2006.
Sensors is indexed and abstracted very quickly by Chemical Abstracts, Analytical
Abstracts, Science Citation Index Expanded, Chemistry Citation Index, Scopus
and Google Scholar.
All papers should be submitted to
sensors@mdpi.org with copy to the guest editors. To be published continuously until the
deadline and papers will be listed together at the special websites.
Please visit the instructions for authors at
http://www.mdpi.org/sensors/publguid.htm before submitting a paper. Open Access publication fees are 1050 CHF
per paper. English correction fees (250 CHF) will be added in certain cases
(1300 CHF per paper for those papers that require extensive additional
formatting and/or English corrections.).
Mr. Matthias BurkhalterAssistant Editor
MDPI Center - Sensors Office
Matthaeusstrasse 11 - CH-4057 Basel / Switzerland
E-mail: sensors@mdpi.org
Tel +41 61 683 7734, Fax +41 61 302 8918
http://www.mdpi.org/sensorsMDPI - Matthias Burkhalter - 12 March 2008