{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T05:40:42Z","timestamp":1770529242350,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2023,7,21]],"date-time":"2023-07-21T00:00:00Z","timestamp":1689897600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"PID2020-114172RB-C21","award":["MCIN\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["MCIN\/AEI\/10.13039\/501100011033"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper reports on the design and experimental validation of a fully-metallic double-ridged waveguide 10 \u00d7 10 Rotman lens additively manufactured as a single part. The wide band operation of this quasi-optical beamformer enables us to cover the uplink and downlink frequencies allocated to satellite communications in the K\/Ka-band, from 17.3 GHz to 30 GHz. The feeding port design was adjusted to enable vertical printing, thus minimizing the use of supporting structures. A prototype was manufactured and tested. The reported results indicate losses in the range of 0.5 dB in the lower-frequency band and 0.8 dB in the upper-frequency band, including the waveguide transitions added for test purposes. The measured reflection and coupling coefficients remain below \u221211.5 dB over the operating band. The standard deviation of the residual phase error across the array ports is below 5\u00b0 in simulation and below 10\u00b0 in measurements. Array factors synthesized using the scattering parameters confirm the good stability of the beamforming functionality over the wide frequency band analyzed. This monolithic design is a promising step toward more integrated antenna systems, such as a compact dual-stack configuration for planar array design.<\/jats:p>","DOI":"10.3390\/s23146573","type":"journal-article","created":{"date-parts":[[2023,7,24]],"date-time":"2023-07-24T03:03:25Z","timestamp":1690167805000},"page":"6573","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Fully-Metallic Additively Manufactured Monolithic Double-Ridged Waveguide Rotman Lens in the K\/Ka-Band"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7971-8706","authenticated-orcid":false,"given":"Nelson J. G.","family":"Fonseca","sequence":"first","affiliation":[{"name":"European Space Agency, 2200AG Noordwijk, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9257-3476","authenticated-orcid":false,"given":"Sophie-Abiga\u00ebl","family":"Gomanne","sequence":"additional","affiliation":[{"name":"European Space Agency, 2200AG Noordwijk, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7703-9526","authenticated-orcid":false,"given":"Jos\u00e9","family":"Rico-Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"TheNextPangea SL, 33418 Asturias, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2505-1886","authenticated-orcid":false,"given":"Petar","family":"Jankovic","sequence":"additional","affiliation":[{"name":"European Space Agency, 2200AG Noordwijk, The Netherlands"}]},{"given":"Jaione","family":"Galdeano","sequence":"additional","affiliation":[{"name":"European Space Agency, 2200AG Noordwijk, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0301-5289","authenticated-orcid":false,"given":"Giovanni","family":"Toso","sequence":"additional","affiliation":[{"name":"European Space Agency, 2200AG Noordwijk, The Netherlands"}]},{"given":"Piero","family":"Angeletti","sequence":"additional","affiliation":[{"name":"European Space Agency, 2200AG Noordwijk, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2487-121X","authenticated-orcid":false,"given":"Manuel","family":"Arrebola","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Universidad de Oviedo, 33203 Gij\u00f3n, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4900-4788","authenticated-orcid":false,"given":"Oscar","family":"Quevedo-Teruel","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, 11428 Stockholm, Sweden"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"807","DOI":"10.1109\/OJAP.2021.3093622","article-title":"Quasi-Optical Multi-Beam Antenna Technologies for B5G and 6G mmWave and THz Networks: A Review","volume":"2","author":"Guo","year":"2021","journal-title":"IEEE Open J. 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