{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:30:22Z","timestamp":1787027422709,"version":"build-2736575974"},"reference-count":24,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,15]],"date-time":"2026-08-15T00:00:00Z","timestamp":1786752000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Shenzhen Science and Technology R&D Funding","award":["KJZD20240903100200001"],"award-info":[{"award-number":["KJZD20240903100200001"]}]},{"name":"Shenzhen Science and Technology R&D Funding","award":["KJZD20231023094659001"],"award-info":[{"award-number":["KJZD20231023094659001"]}]},{"name":"Shenzhen Project","award":["7BJB25010A"],"award-info":[{"award-number":["7BJB25010A"]}]},{"name":"Shenzhen Outstanding Science and Technology Innovation Talent","award":["RCJC20221008092806008"],"award-info":[{"award-number":["RCJC20221008092806008"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["62301126"],"award-info":[{"award-number":["62301126"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"award":["62301126"],"award-info":[{"award-number":["62301126"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012226","name":"Fundamental Research Funds for the Central Universities","doi-asserted-by":"crossref","award":["ZYGX2024Z012"],"award-info":[{"award-number":["ZYGX2024Z012"]}],"id":[{"id":"10.13039\/501100012226","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100012226","name":"Fundamental Research Funds for the Central Universities","doi-asserted-by":"crossref","award":["ZYGX2024XJ009"],"award-info":[{"award-number":["ZYGX2024XJ009"]}],"id":[{"id":"10.13039\/501100012226","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100012226","name":"Fundamental Research Funds for the Central Universities","doi-asserted-by":"crossref","award":["ZYGX2024J006"],"award-info":[{"award-number":["ZYGX2024J006"]}],"id":[{"id":"10.13039\/501100012226","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>This paper presents a 67\u2013110 GHz millimeter-wave RF front end for 6G high-speed wireless communications. A broadband diplexer based on a staggered branch-waveguide structure is first proposed to achieve low insertion loss and high isolation simultaneously. The fabricated diplexer exhibits better than 12 dB return loss, 48.6% fractional bandwidth, and less than 1.5 dB insertion loss. A filtering waveguide-to-microstrip transition is then developed to suppress harmonics and spurious signals while maintaining efficient mode conversion. Back-to-back measurements demonstrate over 50 dB out-of-band suppression at 99.5 GHz with a center frequency of 89 GHz. Finally, the proposed components are integrated with broadband amplifiers, filters, and a local oscillator to realize a 67\u2013110 GHz RF front end with 4\u201326 GHz IF output. Experimental results show harmonic suppression better than 60 dBc, demonstrating excellent spectral purity and validating the proposed architecture as a compact, broadband, and highly integrated solution for future millimeter-wave and terahertz communication systems.<\/jats:p>","DOI":"10.3390\/mi17080962","type":"journal-article","created":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T13:42:17Z","timestamp":1786974137000},"page":"962","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A 67\u2013110 GHz Multi-Carrier Communication Front End Based on Broadband Diplexer and Filtering Waveguide-to-Microstrip Transitions"],"prefix":"10.3390","volume":"17","author":[{"given":"Yujie","family":"Zhi","sequence":"first","affiliation":[{"name":"School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yulong","family":"Zhong","sequence":"additional","affiliation":[{"name":"Chongqing Institute of Microelectronics Industry Technology, University of Electronic Science and Technology of China, Chongqing 401332, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bo","family":"Zhang","sequence":"additional","affiliation":[{"name":"Shenzhen Institute for Advanced Study, University of Electronic Science and Technology of China, Shenzhen 518038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yibo","family":"Fan","sequence":"additional","affiliation":[{"name":"National Local Joint Engineering Laboratory of System Credibility, School of Mathematics, Southwest Jiaotong University, Chengdu 610031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zuqiang","family":"Ou","sequence":"additional","affiliation":[{"name":"Chongqing Institute of Microelectronics Industry Technology, University of Electronic Science and Technology of China, Chongqing 401332, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jincai","family":"Qiao","sequence":"additional","affiliation":[{"name":"Chongqing Institute of Microelectronics Industry Technology, University of Electronic Science and Technology of China, Chongqing 401332, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"220301","DOI":"10.1007\/s11432-025-4604-4","article-title":"Large-capacity long-distance photonics-aided terahertz wireless communication system: Key techniques and experimental demonstration","volume":"68","author":"Zhu","year":"2025","journal-title":"Sci. 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Microw."}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/17\/8\/962\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:15:46Z","timestamp":1787026546000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/17\/8\/962"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,15]]},"references-count":24,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["mi17080962"],"URL":"https:\/\/doi.org\/10.3390\/mi17080962","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,15]]}}}