{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,1]],"date-time":"2025-11-01T05:15:18Z","timestamp":1761974118576,"version":"build-2065373602"},"reference-count":17,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,10,30]],"date-time":"2025-10-30T00:00:00Z","timestamp":1761782400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["62374092","62371470","62404098"],"award-info":[{"award-number":["62374092","62371470","62404098"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Key Research and Development Program of Jiangsu Province","award":["BE2023083"],"award-info":[{"award-number":["BE2023083"]}]},{"name":"Key R&D Program of Zhejiang","award":["2024SSYS0045"],"award-info":[{"award-number":["2024SSYS0045"]}]},{"name":"Ningbo Natural Science Foundation Youth Doctoral Innovation Research Project","award":["2023J397"],"award-info":[{"award-number":["2023J397"]}]},{"name":"Natural Science Foundation of Jiangsu Province of China","award":["BK20241196"],"award-info":[{"award-number":["BK20241196"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>This paper presents a Doppler lidar system based on a mode-locked semiconductor laser (ML-SL) source. The ML-SL consists of two sections: a Fabry\u2013P\u00e9rot (F-P) cavity and a saturable absorber (SA) region. The system utilizes multiple phase-correlated modes of the optical frequency comb to acquire multiple Doppler shift signals; through cross-referencing of these signals, the robustness of the velocimetry system is enhanced. Experimental validation of precise velocity measurements for moving objects was conducted within the speed range of 0.005 m\/s to 0.5 m\/s. For target speeds of 0.563 m\/s and 0.00563 m\/s, the maximum and minimum absolute errors were 0.00064 m\/s and 0.00003 m\/s, respectively, with relative errors consistently below 1%. Comparative experiments demonstrated that utilizing multiple comb teeth reduces the maximum absolute error from 0.001286 m\/s (observed when using a single tooth) to 0.000833 m\/s. Furthermore, the velocity resolution of the system was analyzed: a frequency resolution of 30 Hz corresponds to a velocity resolution of 0.1117 m\/s, while improving the frequency resolution to 1 Hz yields a velocity resolution of 0.0037 m\/s.<\/jats:p>","DOI":"10.3390\/mi16111239","type":"journal-article","created":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T01:23:59Z","timestamp":1761873839000},"page":"1239","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Doppler Lidar Based on Mode-Locked Semiconductor Lasers"],"prefix":"10.3390","volume":"16","author":[{"given":"Yibing","family":"Chen","sequence":"first","affiliation":[{"name":"College of Electronic and Optical Engineering and College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mengxi","family":"Zhou","sequence":"additional","affiliation":[{"name":"College of Electronic and Optical Engineering and College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenxuan","family":"Ma","sequence":"additional","affiliation":[{"name":"College of Electronic and Optical Engineering and College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhenxing","family":"Sun","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Nanjing 210023, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuechun","family":"Shi","sequence":"additional","affiliation":[{"name":"Yongjiang Laboratory, Ningbo 315201, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hui","family":"Zou","sequence":"additional","affiliation":[{"name":"College of Electronic and Optical Engineering and College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7531-2701","authenticated-orcid":false,"given":"Yunshan","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Electronic and Optical Engineering and College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,30]]},"reference":[{"doi-asserted-by":"crossref","unstructured":"Fackelmeier, A., Morhart, C., and Biebl, E. 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