{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T07:02:15Z","timestamp":1769151735207,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,4,5]],"date-time":"2024-04-05T00:00:00Z","timestamp":1712275200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper describes different variants of broadband and simple attenuator modules for beamforming applications, based on radio frequency micro electro-mechanical systems (RF-MEMS), framed within coplanar waveguide (CPW) structures. The modules proposed in the first part of this work differ in their actuation voltage, topology, and desired attenuation level. Fabricated samples of basic 1-bit attenuation modules, characterized by a moderate footprint of 690 \u00d7 1350 \u00b5m2 and aiming at attenuation levels of \u22122, \u22123, and \u22125 dB in the 24.25\u201327.5 GHz range, are presented in their variants featuring both low actuation voltages (5\u20139 V) as well as higher values (~45 V), the latter ones ensuring larger mechanical restoring force (and robustness against stiction). Beyond the fabrication non-idealities that affected the described samples, the substantial agreement between simulations and measurement outcomes proved that the proposed designs could provide precise attenuation levels up to 40 GHz, ranging up to nearly \u22123 dB and \u22125 dB for the series and shunt variants, respectively. Moreover, they could be effective building blocks for future wideband and reconfigurable RF-MEMS attenuators. In fact, in the second part of this work, combinations of the discussed cells and other configurations meant for larger attenuation levels are investigated.<\/jats:p>","DOI":"10.3390\/s24072308","type":"journal-article","created":{"date-parts":[[2024,4,5]],"date-time":"2024-04-05T08:27:52Z","timestamp":1712305672000},"page":"2308","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Discussion and Demonstration of RF-MEMS Attenuators Design Concepts and Modules for Advanced Beamforming in the Beyond-5G and 6G Scenario\u2014Part 1"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7611-6435","authenticated-orcid":false,"given":"Girolamo","family":"Tagliapietra","sequence":"first","affiliation":[{"name":"Center for Sensors and Devices (SD), Fondazione Bruno Kessler (FBK), 38123 Trento, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6009-0103","authenticated-orcid":false,"given":"Flavio","family":"Giacomozzi","sequence":"additional","affiliation":[{"name":"Center for Sensors and Devices (SD), Fondazione Bruno Kessler (FBK), 38123 Trento, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Massimiliano","family":"Michelini","sequence":"additional","affiliation":[{"name":"Center for Sensors and Devices (SD), Fondazione Bruno Kessler (FBK), 38123 Trento, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4815-9470","authenticated-orcid":false,"given":"Romolo","family":"Marcelli","sequence":"additional","affiliation":[{"name":"CNR-IMM, 00133 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3850-2685","authenticated-orcid":false,"given":"Giovanni Maria","family":"Sardi","sequence":"additional","affiliation":[{"name":"CNR-IMM, 00133 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6462-4814","authenticated-orcid":false,"given":"Jacopo","family":"Iannacci","sequence":"additional","affiliation":[{"name":"Center for Sensors and Devices (SD), Fondazione Bruno Kessler (FBK), 38123 Trento, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2547","DOI":"10.1109\/JSSC.2007.907205","article-title":"A 10\u201350-GHz CMOS Distributed Step Attenuator with Low Loss and Low Phase Imbalance","volume":"42","author":"Min","year":"2007","journal-title":"IEEE J. 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