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By replacing the multi-frequency measurements with measurements using multi-length TDR probe, it is possible to retrieve the complex equivalent permittivity of the material in a frequency band of interest. The proposed procedure does not require a priori knowledge of the type of dispersion law of the material, which instead can possibly be inferred from the measured data. The algorithm is validated using numerically simulated data obtained with the commercial code CST Microstudio\u00ae.<\/jats:p>","DOI":"10.3390\/rs14092003","type":"journal-article","created":{"date-parts":[[2022,4,24]],"date-time":"2022-04-24T00:45:21Z","timestamp":1650761121000},"page":"2003","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A Numerical Investigation of the Dispersion Law of Materials by Means of Multi-Length TDR Data"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3213-2879","authenticated-orcid":false,"given":"Raffaele","family":"Persico","sequence":"first","affiliation":[{"name":"Department of Environmental Engineering DIAM, University of Calabria, 87036 Rende, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8401-997X","authenticated-orcid":false,"given":"Iman","family":"Farhat","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Malta, 2080 Msida, Malta"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lourdes","family":"Farrugia","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Malta, 2080 Msida, Malta"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8138-3052","authenticated-orcid":false,"given":"Charles","family":"Sammut","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Malta, 2080 Msida, Malta"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1727","DOI":"10.1109\/TGRS.2005.851163","article-title":"A New Tool for Accurate S-Parameters Measurements and Permittivity Reconstruction","volume":"43","author":"Gorriti","year":"2005","journal-title":"IEEE Trans. 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