{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T19:15:59Z","timestamp":1774379759540,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2021,8,17]],"date-time":"2021-08-17T00:00:00Z","timestamp":1629158400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005416","name":"Norges Forskningsr\u00e5d","doi-asserted-by":"publisher","award":["270959"],"award-info":[{"award-number":["270959"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010198","name":"Ministerio de Econom\u00eda, Industria y Competitividad, Gobierno de Espa\u00f1a","doi-asserted-by":"publisher","award":["ESP2016-79184-R"],"award-info":[{"award-number":["ESP2016-79184-R"]}],"id":[{"id":"10.13039\/501100010198","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["SOE1\/P4\/E0437"],"award-info":[{"award-number":["SOE1\/P4\/E0437"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Radio interference in the uplink makes communication to satellites in the UHF amateur radio band (430\u2013440 MHz) challenging for any satellite application. Interference measurements and characterisation can improve the robustness and reliability of the communication system design. Most published results focus on average power spectrum measurements and heatmaps. We apply a low complexity estimator on an SDR (Software-Defined Radio) to study the interference\u2019s dispersion and temporal variation on-board a small satellite as an alternative. Measuring the Local Mean Envelope (LME) variability with different averaging window lengths enables the estimation of time variability of the interference. The coefficient of variation for the LME indicates how much the signals vary in time and the spread in magnitudes. In this article, theoretical analysis, simulations, and laboratory results were used to validate this measurement method. In-orbit measurements were performed on-board the LUME-1 satellite. Band-limited interference with pulsed temporal behaviour and a high coefficient of variation was detected over North America, Europe, and the Arctic, where space-tracking radars are located. Wide-band pulsed interference with high time variability was also detected over Europe. These measurements show why operators that use a communication system designed for Additive White Gaussian Noise (AWGN) at power levels obtained from heatmaps struggle to command their satellites.<\/jats:p>","DOI":"10.3390\/rs13163252","type":"journal-article","created":{"date-parts":[[2021,8,17]],"date-time":"2021-08-17T21:17:06Z","timestamp":1629235026000},"page":"3252","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["In-Orbit Measurements and Analysis of Radio Interference in the UHF Amateur Radio Band from the LUME-1 Satellite"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6853-6202","authenticated-orcid":false,"given":"Gara","family":"Quintana-Diaz","sequence":"first","affiliation":[{"name":"Department of Electronic Systems, Norwegian University of Science and Technology (NTNU), 7030 Trondheim, Norway"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3413-191X","authenticated-orcid":false,"given":"Torbj\u00f6rn","family":"Ekman","sequence":"additional","affiliation":[{"name":"Department of Electronic Systems, Norwegian University of Science and Technology (NTNU), 7030 Trondheim, Norway"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7976-5166","authenticated-orcid":false,"given":"Jos\u00e9 Miguel","family":"Lago Agra","sequence":"additional","affiliation":[{"name":"Al\u00e9n Space, 36350 Nigr\u00e1n, Spain"}]},{"given":"Diego","family":"Hurtado de Mendoza","sequence":"additional","affiliation":[{"name":"Al\u00e9n Space, 36350 Nigr\u00e1n, Spain"}]},{"given":"Alberto","family":"Gonz\u00e1lez Mu\u00ed\u00f1o","sequence":"additional","affiliation":[{"name":"Al\u00e9n Space, 36350 Nigr\u00e1n, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2713-1943","authenticated-orcid":false,"given":"Fernando","family":"Aguado Agelet","sequence":"additional","affiliation":[{"name":"Department of Electronic Systems, Norwegian University of Science and Technology (NTNU), 7030 Trondheim, Norway"},{"name":"Escola de Enxe\u00f1ar\u00eda de Telecomunicaci\u00f3n, AtlanTTic, University of Vigo, 36350 Vigo, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,17]]},"reference":[{"key":"ref_1","unstructured":"CCSDS (2012). 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