{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T20:39:31Z","timestamp":1768682371008,"version":"3.49.0"},"reference-count":25,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2022,9,19]],"date-time":"2022-09-19T00:00:00Z","timestamp":1663545600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ESA","award":["ITT AO9359"],"award-info":[{"award-number":["ITT AO9359"]}]},{"name":"ESA","award":["RTI2018-099008-B-C21\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["RTI2018-099008-B-C21\/AEI\/10.13039\/501100011033"]}]},{"name":"ESA","award":["FISDUR2020\/105"],"award-info":[{"award-number":["FISDUR2020\/105"]}]},{"name":"project SPOT: Sensing with Pioneering Opportunistic Techniques","award":["ITT AO9359"],"award-info":[{"award-number":["ITT AO9359"]}]},{"name":"project SPOT: Sensing with Pioneering Opportunistic Techniques","award":["RTI2018-099008-B-C21\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["RTI2018-099008-B-C21\/AEI\/10.13039\/501100011033"]}]},{"name":"project SPOT: Sensing with Pioneering Opportunistic Techniques","award":["FISDUR2020\/105"],"award-info":[{"award-number":["FISDUR2020\/105"]}]},{"name":"recruitment of early stage research staff of the Ag\u00e8ncia de Gesti\u00f3 d\u2019Ajuts Universitaris i de Recerca (AGAUR) Generalitat de Catalunya, Spain","award":["ITT AO9359"],"award-info":[{"award-number":["ITT AO9359"]}]},{"name":"recruitment of early stage research staff of the Ag\u00e8ncia de Gesti\u00f3 d\u2019Ajuts Universitaris i de Recerca (AGAUR) Generalitat de Catalunya, Spain","award":["RTI2018-099008-B-C21\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["RTI2018-099008-B-C21\/AEI\/10.13039\/501100011033"]}]},{"name":"recruitment of early stage research staff of the Ag\u00e8ncia de Gesti\u00f3 d\u2019Ajuts Universitaris i de Recerca (AGAUR) Generalitat de Catalunya, Spain","award":["FISDUR2020\/105"],"award-info":[{"award-number":["FISDUR2020\/105"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This work presents the first RFI detection and mitigation algorithm for the interferometric radiometers that will be implemented in its correlator unit. The algorithm operates in the time and frequency domains, applying polarimetric and statistical tests in both domains, and exhibiting a tunable and arbitrary low probability of false alarm. It is scalable to a configurable number of receivers, and it is optimized in terms of quantization bits and the implementation of the cross-correlations in the time or frequency domains for hardware resource saving. New features of this algorithm are the computation of the Stokes parameters per frequency bin in the Short-Time Fourier Transform and a new parameter called Polarimetric Kurtosis. If RFI is detected in one domain or in both, it is removed using the calculated blanking masks. The optimum algorithm parameters are computed, such as length of the FFTs, the threshold selection for a given probability of false alarm, and the selection of the blanking masks. Last, an important result refers to the application of Parseval\u2019s theorem for the computation of the cross-correlations in the frequency domain, instead of in the time domain, which is more efficient and leads to smaller errors even when using moderate quantization levels. The algorithm has been developed in the framework of the ESA\u2019s technology preparation for a potential L-band radiometer mission beyond SMOS. However, it is also applicable to (polarimetric) real aperture radiometers, and its performance would improve if more than one bit is used in the signal quantization.<\/jats:p>","DOI":"10.3390\/rs14184672","type":"journal-article","created":{"date-parts":[[2022,9,20]],"date-time":"2022-09-20T04:28:55Z","timestamp":1663648135000},"page":"4672","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["RFI Detection and Mitigation for Advanced Correlators in Interferometric Radiometers"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2736-1028","authenticated-orcid":false,"given":"Adrian","family":"Perez-Portero","sequence":"first","affiliation":[{"name":"CommSensLab, Department of Signal Theory and Communications, Universitat Polit\u00e8cnica de Catalunya, c\/Jordi Girona 1\u20133, 08034 Barcelona, Spain"},{"name":"MITIC Solutions S.L., 08017 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8500-5534","authenticated-orcid":false,"given":"Jorge","family":"Querol","sequence":"additional","affiliation":[{"name":"MITIC Solutions S.L., 08017 Barcelona, Spain"},{"name":"Interdisciplinary Centre for Security, Reliability and Trust (SnT), University of Luxembourg, 1855 Luxembourg, Luxembourg"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9514-4992","authenticated-orcid":false,"given":"Adriano","family":"Camps","sequence":"additional","affiliation":[{"name":"CommSensLab, Department of Signal Theory and Communications, Universitat Polit\u00e8cnica de Catalunya, c\/Jordi Girona 1\u20133, 08034 Barcelona, Spain"},{"name":"MITIC Solutions S.L., 08017 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7626-7033","authenticated-orcid":false,"given":"Manuel","family":"Martin-Neira","sequence":"additional","affiliation":[{"name":"European Space Agency, ESTEC, 2201 Noordwijk, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Martin","family":"Suess","sequence":"additional","affiliation":[{"name":"European Space Agency, ESTEC, 2201 Noordwijk, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juan Ignacio","family":"Ramirez","sequence":"additional","affiliation":[{"name":"Airbus Madrid, 28001 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alberto","family":"Zurita","sequence":"additional","affiliation":[{"name":"Airbus Madrid, 28001 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Josep","family":"Closa","sequence":"additional","affiliation":[{"name":"Airbus Madrid, 28001 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roger","family":"Oliva","sequence":"additional","affiliation":[{"name":"Zenithal Blue Technologies, 08023 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raul","family":"Onrubia","sequence":"additional","affiliation":[{"name":"Zenithal Blue Technologies, 08023 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,19]]},"reference":[{"key":"ref_1","unstructured":"Gasiewski, A., Klein, M., Yevgrafov, A., and Leuskiy, V. 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