{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:40:47Z","timestamp":1760244047220,"version":"build-2065373602"},"reference-count":18,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2009,6,12]],"date-time":"2009-06-12T00:00:00Z","timestamp":1244764800000},"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>Accurate models are used today for infrared and microwave satellite radiance simulations of the first two Stokes elements in the physical retrieval, data assimilation etc. of surface and atmospheric parameters. Although in the past a number of theoretical and experimental works have studied the polarimetric emission of some natural surfaces, specially the sea surface roughened by the wind (Windsat mission), very limited studies have been conducted on the polarimetric emission of rain cells or other natural surfaces. In this work, the polarimetric emission (four Stokes elements) of a rain cell is computed using the polarimetric radiative transfer equation assuming that raindrops are described by Pruppacher-Pitter shapes and that their size distribution follows the Laws-Parsons law. The Boundary Element Method (BEM) is used to compute the exact bistatic scattering coefficients for each raindrop shape and different canting angles. Numerical results are compared to the Rayleigh or Mie scattering coefficients, and to Oguchi\u2019s ones, showing that above 1-2 mm raindrop size the exact formulation is required to model properly the scattering. Simulation results using BEM are then compared to the experimental data gathered with a X-band polarimetric radiometer. It is found that the depolarization of the radiation caused by the scattering of non-spherical raindrops induces a non-zero third Stokes parameter, and the differential phase of the scattering coefficients induces a non-zero fourth Stokes parameter.<\/jats:p>","DOI":"10.3390\/rs1020107","type":"journal-article","created":{"date-parts":[[2009,6,12]],"date-time":"2009-06-12T12:03:20Z","timestamp":1244808200000},"page":"107-121","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Polarimetric Emission of Rain Events: Simulation and Experimental Results at X-Band"],"prefix":"10.3390","volume":"1","author":[{"given":"Nuria","family":"Duffo","sequence":"first","affiliation":[{"name":"Dept. of Signal Theory and Communications, Universitat Polit\u00e8cnica de Catalunya, UPC Campus Nord D3, E-08034 Barcelona, Spain, and SMOS Barcelona Expert Centre, Pg. Mar\u00edtim de la Barceloneta 37-49, E-08003, Barcelona, Spain"}]},{"given":"Mercedes","family":"Vall llossera","sequence":"additional","affiliation":[{"name":"Dept. of Signal Theory and Communications, Universitat Polit\u00e8cnica de Catalunya, UPC Campus Nord D3, E-08034 Barcelona, Spain, and SMOS Barcelona Expert Centre, Pg. Mar\u00edtim de la Barceloneta 37-49, E-08003, Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9514-4992","authenticated-orcid":false,"given":"Adriano","family":"Camps","sequence":"additional","affiliation":[{"name":"Dept. of Signal Theory and Communications, Universitat Polit\u00e8cnica de Catalunya, UPC Campus Nord D3, E-08034 Barcelona, Spain, and SMOS Barcelona Expert Centre, Pg. Mar\u00edtim de la Barceloneta 37-49, E-08003, Barcelona, Spain"}]},{"given":"Ignasi","family":"Corbella","sequence":"additional","affiliation":[{"name":"Dept. of Signal Theory and Communications, Universitat Polit\u00e8cnica de Catalunya, UPC Campus Nord D3, E-08034 Barcelona, Spain, and SMOS Barcelona Expert Centre, Pg. Mar\u00edtim de la Barceloneta 37-49, E-08003, Barcelona, Spain"}]},{"given":"Francesc","family":"Torres","sequence":"additional","affiliation":[{"name":"Dept. of Signal Theory and Communications, Universitat Polit\u00e8cnica de Catalunya, UPC Campus Nord D3, E-08034 Barcelona, Spain, and SMOS Barcelona Expert Centre, Pg. Mar\u00edtim de la Barceloneta 37-49, E-08003, Barcelona, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2009,6,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Liu, Q., Weng, F., Han, Y., and van Delst, P. (,  2008). Community Radiative Transfer Model for Scattering Transfer and Applications. 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AGU."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1029\/RS008i001p00031","article-title":"Attenuation and phase rotation of radio waves due to rain: calculations at 19.3 and 34.8 GHz","volume":"8","author":"Oguchi","year":"1973","journal-title":"Radio Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"691","DOI":"10.1029\/RS016i005p00691","article-title":"Scattering from hydrometeors: a survey","volume":"16","author":"Oguchi","year":"1981","journal-title":"Radio Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1029\/RS012i001p00041","article-title":"Scattering properties of pruppacher-and-pitter form raindrops and cross polarization due to rain: calculations at 11, 13, 19.3 and 34.8 GHz","volume":"12","author":"Oguchi","year":"1977","journal-title":"Radio Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"682","DOI":"10.1109\/22.3572","article-title":"Three-dimensional finite, boundary, and hybrid element solutions of the maxwell equations for lossy dielectric media","volume":"36","author":"Paulsen","year":"1988","journal-title":"IEEE Trans. Microwave Theory"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/1\/2\/107\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:10:34Z","timestamp":1760220634000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/1\/2\/107"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,6,12]]},"references-count":18,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2009,6]]}},"alternative-id":["rs1020107"],"URL":"https:\/\/doi.org\/10.3390\/rs1020107","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2009,6,12]]}}}