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High-Efficiency Autonomous Coherent LidarA useful measure of sensor performance is the transceiver system efficiency n (sub sys). Which consists of the antenna efficiency n (sub a) and optical and electronic losses. Typically, the lidar equation and the antenna efficiency are defined in terms of the telescope aperture area. However, during the assembly of a coherent transceiver, it is important to measure the system efficiency before the installation of the beamexpanding telescope (i.e., the untruncated-beam system efficiency). Therefore, to accommodate both truncated and untruncated beam efficiency measurements, we define the lidar equation and the antenna efficiency in terms of the beam area rather than the commonly used aperture area referenced definition. With a well-designed Gaussian-beam lidar, aperture area referenced system efficiencies of 15 to 20 % (23-31% relative to the beam area) are readily achievable. In this paper we compare the differences between these efficiency definitions. We then describe techniques by which high efficiency can be achieved, followed by a discussion several novel auto alignment techniques developed to maintain high efficiency.
Document ID
20000013014
Acquisition Source
Marshall Space Flight Center
Document Type
Conference Paper
Authors
Gatt, Philip
(Coherent Technologies, Inc. Lafayette, CO United States)
Henderson, Sammy W.
(Coherent Technologies, Inc. Lafayette, CO United States)
Hannon, Stephen M.
(Coherent Technologies, Inc. Lafayette, CO United States)
Date Acquired
August 19, 2013
Publication Date
November 1, 1999
Publication Information
Publication: Tenth Biennial Coherent Laser Radar Technology and Applications Conference
Subject Category
Instrumentation And Photography
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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