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Atmospheric contributions to the column variance in direct-detection dialOne of the most important parameters of a Differential Absorption Lidar (DIAL) system is the delay time between the on and off resonant pulses. It is important that this delay time is sufficiently small to ensure that the atmosphere is effectively frozen between the pulses. Therefore, most Dial systems were designed with two lasers firing alternately less than 1 msec apart. Despite the importance of this parameter in the design of DIAL systems and its contribution to the overall error of a column measurement, very little is known about the size of the error for the case of a direct-detection system using atmospheric backscatter. The ultraviolet DIAL system uses two independent YAG/dye lasers and is therefore suitable for measuring the effects of different pulse delays on the variance of column measurements for a variety of atmospheric conditions. A set of DIAL returns were acquired with the two lasers tuned to the same wavelength and with a range of pulse delay times between 250 microseconds and several minutes. This data set was recorded in full on a computer and was used both to test different averaging techniques and also to evaluate atmospheric contributions to DIAL columns.
Document ID
19870000856
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Milton, M. J. T.
(National Physical Lab. Teddington, United Kingdom)
Woods, P. T.
(National Physical Lab. Teddington, United Kingdom)
Date Acquired
August 13, 2013
Publication Date
August 1, 1986
Publication Information
Publication: NASA. Langley Research Center 13th International Laser Radar Conference
Subject Category
Lasers And Masers
Accession Number
87N10289
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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