{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:25:47Z","timestamp":1760235947699,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2021,10,14]],"date-time":"2021-10-14T00:00:00Z","timestamp":1634169600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["Project-ID 287022738 TRR 196"],"award-info":[{"award-number":["Project-ID 287022738 TRR 196"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002347","name":"Federal Ministry of Education and Research","doi-asserted-by":"publisher","award":["grant number 01DD20001"],"award-info":[{"award-number":["grant number 01DD20001"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Self-localization based on passive RFID-based has many potential applications. One of the main challenges it faces is the suppression of the reflected signals from unwanted objects (i.e., clutter). Typically, the clutter echoes are much stronger than the backscattered signals of the passive tag landmarks used in such scenarios. Therefore, successful tag detection can be very challenging. We consider two types of tags, namely low-Q and high-Q tags. The high-Q tag features a sparse frequency response, whereas the low-Q tag presents a broad frequency response. Further, the clutter usually showcases a short-lived response. In this work, we propose an iterative algorithm based on a low-rank plus sparse recovery approach (RPCA) to mitigate clutter and retrieve the landmark response. In addition to that, we compare the proposed approach with the well-known time-gating technique. It turns out that RPCA outperforms significantly time-gating for low-Q tags, achieving clutter suppression and tag identification when clutter encroaches on the time-gating window span, whereas it also increases the backscattered power at resonance by approximately 12 dB at 80 cm for high-Q tags. Altogether, RPCA seems a promising approach to improve the identification of passive indoor self-localization tag landmarks.<\/jats:p>","DOI":"10.3390\/s21206842","type":"journal-article","created":{"date-parts":[[2021,10,14]],"date-time":"2021-10-14T23:02:16Z","timestamp":1634252536000},"page":"6842","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Clutter Suppression for Indoor Self-Localization Systems by Iteratively Reweighted Low-Rank Plus Sparse Recovery"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8451-3430","authenticated-orcid":false,"given":"Jes\u00fas","family":"S\u00e1nchez-Pastor","sequence":"first","affiliation":[{"name":"Institute of Microwave Engineering and Photonics, Technical University of Darmstadt, 64283 Darmstadt, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0009-9496","authenticated-orcid":false,"given":"Udaya S. K. P.","family":"Miriya Thanthrige","sequence":"additional","affiliation":[{"name":"Institute of Digital Communication Systems, Ruhr University Bochum, 44801 Bochum, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8893-3945","authenticated-orcid":false,"given":"Furkan","family":"Ilgac","sequence":"additional","affiliation":[{"name":"Institute of Digital Communication Systems, Ruhr University Bochum, 44801 Bochum, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0468-1352","authenticated-orcid":false,"given":"Alejandro","family":"Jim\u00e9nez-S\u00e1ez","sequence":"additional","affiliation":[{"name":"Institute of Microwave Engineering and Photonics, Technical University of Darmstadt, 64283 Darmstadt, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7679-9697","authenticated-orcid":false,"given":"Peter","family":"Jung","sequence":"additional","affiliation":[{"name":"Institute of Communications and Information Theory, Technical University Berlin, 10587 Berlin, Germany"},{"name":"Data Science in Earth Observation, Technical University of Munich, 82024 Taufkirchen\/Ottobrunn, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3511-2662","authenticated-orcid":false,"given":"Aydin","family":"Sezgin","sequence":"additional","affiliation":[{"name":"Institute of Digital Communication Systems, Ruhr University Bochum, 44801 Bochum, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6568-830X","authenticated-orcid":false,"given":"Rolf","family":"Jakoby","sequence":"additional","affiliation":[{"name":"Institute of Microwave Engineering and Photonics, Technical University of Darmstadt, 64283 Darmstadt, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Sanpechuda, T., and Kovavisaruch, L. 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