Roy, AnirbanAnirbanRoyChakraborty, Arup LalArup LalChakraborty2025-08-312025-08-312019-12-01[9781728147499]10.1109/WRAP47485.2019.90137342-s2.0-85082172688https://d8.irins.org/handle/IITG2025/24350We report the design, development and field deployment of a quantum cascade laser-based tunable diode laser spectroscopy (TDLS) system for high-sensitivity measurement of atmospheric CO and CO<inf>2</inf>. Two distributed-feedback quantum cascade lasers are used to interrogate the rotational-vibrational transitions of CO at 4594.99 nm and CO<inf>2</inf> at 4319.30 nm. The mean mole fraction values for CO and CO<inf>2</inf> for the measurements made at Gandhinagar from 19-25 July 2019 are 477 ppb and 486 ppm respectively. The detection limit of the system is 3 ppb CO and 45 ppb CO<inf>2</inf> for integration time of 17 s and 69 s respectively.falseair quality monitoring | greenhouse gas monitoring | quantum cascade laser | wavelength modulation spectroscopyConference PaperDecember 201919013734cpConference Proceeding1