{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T01:53:54Z","timestamp":1772762034333,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2012,5,9]],"date-time":"2012-05-09T00:00:00Z","timestamp":1336521600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>We demonstrate compact, low power, lightweight laser-based sensors for measuring trace gas species in the atmosphere designed specifically for electronic unmanned aerial vehicle (UAV) platforms. The sensors utilize non-intrusive optical sensing techniques to measure atmospheric greenhouse gas concentrations with unprecedented vertical and horizontal resolution (~1 m) within the planetary boundary layer. The sensors are developed to measure greenhouse gas species including carbon dioxide, water vapor and methane in the atmosphere. Key innovations are the coupling of very low power vertical cavity surface emitting lasers (VCSELs) to low power drive electronics and sensitive multi-harmonic wavelength modulation spectroscopic techniques. The overall mass of each sensor is between 1\u20132 kg including batteries and each one consumes less than 2 W of electrical power. In the initial field testing, the sensors flew successfully onboard a T-Rex Align 700E robotic helicopter and showed a precision of 1% or less for all three trace gas species. The sensors are battery operated and capable of fully automated operation for long periods of time in diverse sensing environments. Laser-based trace gas sensors for UAVs allow for high spatial mapping of local greenhouse gas concentrations in the atmospheric boundary layer where land\/atmosphere fluxes occur. The high-precision sensors, coupled to the ease-of-deployment and cost effectiveness of UAVs, provide unprecedented measurement capabilities that are not possible with existing satellite-based and suborbital aircraft platforms.<\/jats:p>","DOI":"10.3390\/rs4051355","type":"journal-article","created":{"date-parts":[[2012,5,9]],"date-time":"2012-05-09T12:14:00Z","timestamp":1336565640000},"page":"1355-1368","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":116,"title":["Low Power Greenhouse Gas Sensors for Unmanned Aerial Vehicles"],"prefix":"10.3390","volume":"4","author":[{"given":"Amir","family":"Khan","sequence":"first","affiliation":[{"name":"Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544, USA"},{"name":"Center for Mid-Infrared Technologies for Health and the Environment NSF-ERC, Princeton University, Princeton, NJ 08540, USA"}]},{"given":"David","family":"Schaefer","sequence":"additional","affiliation":[{"name":"William B. Hanson Center for Space Science, Department of Physics, University of Texas, Dallas, TX 75080, USA"}]},{"given":"Lei","family":"Tao","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544, USA"},{"name":"Center for Mid-Infrared Technologies for Health and the Environment NSF-ERC, Princeton University, Princeton, NJ 08540, USA"}]},{"given":"David J.","family":"Miller","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544, USA"},{"name":"Center for Mid-Infrared Technologies for Health and the Environment NSF-ERC, Princeton University, Princeton, NJ 08540, USA"}]},{"given":"Kang","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544, USA"},{"name":"Center for Mid-Infrared Technologies for Health and the Environment NSF-ERC, Princeton University, Princeton, NJ 08540, USA"}]},{"given":"Mark A.","family":"Zondlo","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544, USA"},{"name":"Center for Mid-Infrared Technologies for Health and the Environment NSF-ERC, Princeton University, Princeton, NJ 08540, USA"}]},{"given":"William A.","family":"Harrison","sequence":"additional","affiliation":[{"name":"William B. Hanson Center for Space Science, Department of Physics, University of Texas, Dallas, TX 75080, USA"}]},{"given":"Bryan","family":"Roscoe","sequence":"additional","affiliation":[{"name":"William B. Hanson Center for Space Science, Department of Physics, University of Texas, Dallas, TX 75080, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4265-9543","authenticated-orcid":false,"given":"David J.","family":"Lary","sequence":"additional","affiliation":[{"name":"William B. Hanson Center for Space Science, Department of Physics, University of Texas, Dallas, TX 75080, USA"}]}],"member":"1968","published-online":{"date-parts":[[2012,5,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"L06303","DOI":"10.1029\/2007GL032508","article-title":"Unmanned aerial vehicle measurements of volcanic carbon dioxide fluxes","volume":"35","author":"McGonigle","year":"2008","journal-title":"Geophys. Res. 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