{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,19]],"date-time":"2026-02-19T02:18:20Z","timestamp":1771467500985,"version":"3.50.1"},"reference-count":29,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,15]],"date-time":"2023-09-15T00:00:00Z","timestamp":1694736000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Natural Science Foundation of China","award":["62101518"],"award-info":[{"award-number":["62101518"]}]},{"name":"the National Natural Science Foundation of China","award":["U2241276"],"award-info":[{"award-number":["U2241276"]}]},{"name":"the National Natural Science Foundation of China","award":["JCKYS2022212001"],"award-info":[{"award-number":["JCKYS2022212001"]}]},{"name":"the Foundation of National Key Laboratory of Shock Wave and Detonation Physics","award":["62101518"],"award-info":[{"award-number":["62101518"]}]},{"name":"the Foundation of National Key Laboratory of Shock Wave and Detonation Physics","award":["U2241276"],"award-info":[{"award-number":["U2241276"]}]},{"name":"the Foundation of National Key Laboratory of Shock Wave and Detonation Physics","award":["JCKYS2022212001"],"award-info":[{"award-number":["JCKYS2022212001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A microwave absolute distance measurement method with ten-micron-level accuracy and meter-level range based on frequency domain interferometry is proposed and experimentally demonstrated for the first time. Theoretical analysis indicates that an interference phenomenon occurs instantaneously in the frequency domain when combining two homologous broad-spectrum microwave beams with different paths, and the absolute value of the distance difference between the two paths is only inversely proportional to the period of frequency domain interference fringes. The proof-of-principle experiments were performed to prove that the proposed method can achieve absolute distance measurement in the X-band with standard deviations of 15 \u03bcm, 17 \u03bcm, and 26 \u03bcm and within ranges of 1.69 m, 2.69 m, and 3.75 m. Additionally, a displacement resolution of 100 microns was realized. The multi-target recognition performance was also verified in principle. Furthermore, at the expense of a slight decrease in ranging accuracy, a fast distance measurement with the single measurement time of 20 \u03bcs was achieved by using a digitizer combined with a Fourier transform analyzer. Compared with the current microwave precision ranging technologies, the proposed method not only has the advantages of high precision, large range, and rapid measurement capability, but the required components are also easily obtainable commercial devices. The proposed method also has better complex engineering applicability, because the ten-micron-level ranging accuracy is achievable only by using a simple Fourier transform without any phase estimation algorithm, which greatly reduces the requirement for signal-to-noise ratio.<\/jats:p>","DOI":"10.3390\/s23187898","type":"journal-article","created":{"date-parts":[[2023,9,15]],"date-time":"2023-09-15T04:06:13Z","timestamp":1694750773000},"page":"7898","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Microwave Absolute Distance Measurement Method with Ten-Micron-Level Accuracy and Meter-Level Range Based on Frequency Domain Interferometry"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5436-8754","authenticated-orcid":false,"given":"Longhuang","family":"Tang","sequence":"first","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Xing","family":"Jia","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Heli","family":"Ma","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Shenggang","family":"Liu","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Yongchao","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Tianjiong","family":"Tao","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Long","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Jian","family":"Wu","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Chengjun","family":"Li","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Xiang","family":"Wang","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]},{"given":"Jidong","family":"Weng","sequence":"additional","affiliation":[{"name":"Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"},{"name":"National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1692","DOI":"10.1109\/TMTT.2017.2650911","article-title":"A Review on Recent Progress of Portable Short-Range Noncontact Microwave Radar Systems","volume":"65","author":"Li","year":"2017","journal-title":"IEEE Trans. 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