title: Long-term outdoor reliability assessment of a wireless unit for air-quality monitoring based on nanostructured films integrated on micromachined platforms.
abstract: We have fabricated and tested in long-term field operating conditions a wireless unit for outdoor air quality monitoring. The unit is equipped with two multiparametric sensors, one miniaturized thermo-hygrometer, front-end analogical and digital electronics, and an IEEE 802.15.4 based module for wireless data transmission. Micromachined platforms were functionalized with nanoporous metal-oxides to obtain multiparametric sensors, hosting gas-sensitive, anemometric and temperature transducers. Nanoporous metal-oxide layer was directly deposited on gas sensing regions of micromachined platform batches by hard-mask patterned supersonic cluster beam deposition. An outdoor, roadside experiment was arranged in downtown Milan (Italy), where one wireless sensing unit was continuously operated side by side with standard gas chromatographic instrumentation for air quality measurements. By means of a router PC, data from sensing unit and other instrumentation were collected, merged, and sent to a remote data storage server, through an UMTS device. The whole-system robustness as well as sensor dataset characteristics were continuously characterized over a run-time period of 18 months.
authors.affiliation: Tethis spa, via Russoli 3, Milano 20143, Italy. matteo.leccardi@tethis-lab.com
authors.forename: Matteo
authors.initials: M
authors.lastname: Leccardi
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Decarli
authors.forename: Leandro
authors.initials: L
authors.lastname: Lorenzelli
authors.forename: Paolo
authors.initials: P
authors.lastname: Milani
authors.forename: Petteri
authors.initials: P
authors.lastname: Mettala
authors.forename: Risto
authors.initials: R
authors.lastname: Orava
authors.forename: Emanuele
authors.initials: E
authors.lastname: Barborini