{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T15:50:35Z","timestamp":1772207435536,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2019,8,12]],"date-time":"2019-08-12T00:00:00Z","timestamp":1565568000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>Plasma diagnostics is a topic of great interest in the physics and engineering community because the monitoring of plasma parameters plays a fundamental role in the development and optimization of plasma reactors. Towards this aim, microwave diagnostics, such as reflectometric, interferometric, and polarimetric techniques, can represent effective means. Besides the above, microwave imaging profilometry (MIP) may allow the obtaining of tomographic, i.e., volumetric, information of plasma that could overcome some intrinsic limitations of the standard non-invasive diagnostic approaches. However, pursuing MIP is not an easy task due to plasma\u2019s electromagnetic features, which strongly depend on the working frequency, angle of incidence, polarization, etc., as well as on the need for making diagnostics in both large (meter-sized) and small (centimeter-sized) reactors. Furthermore, these latter represent extremely harsh environments, wherein different systems and equipment need to coexist to guarantee their functionality. Specifically, MIP entails solution of an inverse scattering problem, which is non-linear and ill-posed, and, in addition, in the one-dimensional case, is also severely limited in terms of achievable reconstruction accuracy and resolution. In this contribution, we address microwave inverse profiling of plasma assuming a high-frequency probing regime when magnetically confined plasma can be approximated as both an isotropic and weak penetrable medium. To this aim, we adopt a finite-difference frequency-domain (FDFD) formulation which allows dealing with non-homogeneous backgrounds introduced by unavoidable presence of plasma reactors.<\/jats:p>","DOI":"10.3390\/jimaging5080070","type":"journal-article","created":{"date-parts":[[2019,8,12]],"date-time":"2019-08-12T06:38:02Z","timestamp":1565591882000},"page":"70","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["A Finite-Difference Approach for Plasma Microwave Imaging Profilometry"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2504-0223","authenticated-orcid":false,"given":"Loreto","family":"Di Donato","sequence":"first","affiliation":[{"name":"Department of Electrical, Electronics and Computer Engineering (DIEEI), University of Catania, viale A. Doria 6, 95126 Catania, Italy"},{"name":"Laboratori Nazionali del Sud, National Institute of Nuclear Physics (INFN), Via Santa Sofia 62, 95125 Catania, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3861-1547","authenticated-orcid":false,"given":"David","family":"Mascali","sequence":"additional","affiliation":[{"name":"Laboratori Nazionali del Sud, National Institute of Nuclear Physics (INFN), Via Santa Sofia 62, 95125 Catania, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7502-6238","authenticated-orcid":false,"given":"Andrea F.","family":"Morabito","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, Infrastructures and Sustainable Energy (DIIES), University \u201cMediterranea\u201d of Reggio Calabria, via Graziella, Loc. Feo di Vito, 89124 Reggio di Calabria, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5081-3486","authenticated-orcid":false,"given":"Gino","family":"Sorbello","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronics and Computer Engineering (DIEEI), University of Catania, viale A. Doria 6, 95126 Catania, Italy"},{"name":"Laboratori Nazionali del Sud, National Institute of Nuclear Physics (INFN), Via Santa Sofia 62, 95125 Catania, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,8,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"035012","DOI":"10.1088\/1361-6595\/ab093c","article-title":"Sparse data recovery of tomographic diagnostics for ultra-large-area plasmas","volume":"28","author":"Park","year":"2019","journal-title":"Plasma Sour. Sci. 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