{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T13:13:53Z","timestamp":1790082833139,"version":"4.0.1"},"reference-count":21,"publisher":"AIP Publishing","issue":"9","funder":[{"DOI":"10.13039\/501100013282","name":"National Magnetic Confinement Fusion Program of China","doi-asserted-by":"publisher","award":["2019YFE03020001"],"award-info":[{"award-number":["2019YFE03020001"]}],"id":[{"id":"10.13039\/501100013282","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,9,1]]},"abstract":"<jats:p>Millimeter-wave interferometry is a standard diagnostic for line-integrated electron density, but conventional implementations typically rely on discrete high-frequency sources, mixers, and separately aligned reference paths. Here, we report an integrated frequency-modulated continuous-wave interferometer for plasma diagnostics using a commercial 60\u201364\u00a0GHz radar system-on-chip and, critically, an in situ common-path reference architecture that enables phase-stable operation with industrial hardware. The key design feature is the intentional use of aperture-clipping reflection from the diagnostic-window flange as a stationary reference echo, while the transmitted beam core traverses the plasma and is reflected by a mirror. Because the reference and measurement echoes are generated by the same chirp and share the same transceiver, launch optics, and diagnostic port, differential phase extraction suppresses common-mode oscillator drift, thermal drift, and mechanical vibration without a separate reference arm. A high-duty-cycle chirp configuration and chirp-by-chirp FFT phase retrieval provide a temporal resolution of 120 \u03bcs. Experiments on the Keda Linear Magnetized Plasma device show that the common-path-referenced scheme reduces the phase standard deviation from 0.34\u00b0 to 0.17\u00b0 and suppresses the dominant 22\u00a0Hz vibration component by more than 12 dB, yielding a minimum detectable line-integrated density of 2 \u00d7 1014\u00a0m\u22122. These results demonstrate a compact and scalable interferometer architecture for plasma diagnostics based on commercially integrated millimeter-wave hardware.<\/jats:p>","DOI":"10.1063\/5.0335743","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T12:55:50Z","timestamp":1790081750000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["Integrated frequency-modulated continuous-wave (FMCW) interferometer with\n                    <i>in situ<\/i>\n                    common-path referencing for plasma diagnostics using a commercial radar system-on-chip"],"prefix":"10.1063","volume":"97","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-4684-9226","authenticated-orcid":false,"given":"Jinuo","family":"Yu","sequence":"first","affiliation":[{"name":"Department of Plasma Physics and Fusion Engineering, School of Nuclear Science and Technology, University of Science and Technology of China 1 , 96 Jinzhai Road, Hefei,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8902-672X","authenticated-orcid":false,"given":"Jinlin","family":"Xie","sequence":"additional","affiliation":[{"name":"Department of Plasma Physics and Fusion Engineering, School of Nuclear Science and Technology, University of Science and Technology of China 1 , 96 Jinzhai Road, Hefei,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"RuoXuan","family":"Guo","sequence":"additional","affiliation":[{"name":"Binhu Campus, Hefei No. 1 High School 2 , Hefei, Anhui,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinchen","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Plasma Physics and Fusion Engineering, School of Nuclear Science and Technology, University of Science and Technology of China 1 , 96 Jinzhai Road, Hefei,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yiduo","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Plasma Physics and Fusion Engineering, School of Nuclear Science and Technology, University of Science and Technology of China 1 , 96 Jinzhai Road, Hefei,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6048-8568","authenticated-orcid":false,"given":"Ge","family":"Zhuang","sequence":"additional","affiliation":[{"name":"Department of Plasma Physics and Fusion Engineering, School of Nuclear Science and Technology, University of Science and Technology of China 1 , 96 Jinzhai Road, Hefei,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2026,9,22]]},"reference":[{"issue":"6","key":"2026092208554413000_c1","doi-asserted-by":"publisher","first-page":"605","DOI":"10.1088\/0029-5515\/11\/6\/005","article-title":"Plasma equilibrium in a tokamak","volume":"11","year":"1971","journal-title":"Nucl. 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