{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,24]],"date-time":"2025-12-24T06:26:45Z","timestamp":1766557605359,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2016,9,24]],"date-time":"2016-09-24T00:00:00Z","timestamp":1474675200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Joint Doctorial Fund Project from the Ministry of Education","award":["2013142012007"],"award-info":[{"award-number":["2013142012007"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper proposes a time-frequency algorithm based on short-time fractional order Fourier transformation (STFRFT) for identification of a complicated movement targets. This algorithm, consisting of a STFRFT order-changing and quick selection method, is effective in reducing the computation load. A multi-order STFRFT time-frequency algorithm is also developed that makes use of the time-frequency feature of each micro-Doppler component signal. This algorithm improves the estimation accuracy of time-frequency curve fitting through multi-order matching. Finally, experiment data were used to demonstrate STFRFT\u2019s performance in micro-Doppler time-frequency analysis. The results validated the higher estimate accuracy of the proposed algorithm. It may be applied to an LFM (Linear frequency modulated) pulse radar, SAR (Synthetic aperture radar), or ISAR (Inverse synthetic aperture radar), for improving the probability of target recognition.<\/jats:p>","DOI":"10.3390\/s16101559","type":"journal-article","created":{"date-parts":[[2016,9,26]],"date-time":"2016-09-26T10:02:44Z","timestamp":1474884164000},"page":"1559","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Micro-Doppler Signal Time-Frequency Algorithm Based on STFRFT"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8523-5196","authenticated-orcid":false,"given":"Cunsuo","family":"Pang","sequence":"first","affiliation":[{"name":"National Key Laboratory for Electronic Measurement Technology, North University of China, Taiyuan 030051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yan","family":"Han","sequence":"additional","affiliation":[{"name":"National Key Laboratory for Electronic Measurement Technology, North University of China, Taiyuan 030051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huiling","family":"Hou","sequence":"additional","affiliation":[{"name":"National Key Laboratory for Electronic Measurement Technology, North University of China, Taiyuan 030051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6579-9798","authenticated-orcid":false,"given":"Shengheng","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Information and Electronics, Beijing Institute of Technology, Beijing 10081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nan","family":"Zhang","sequence":"additional","affiliation":[{"name":"The Second System Design Department of Second Research Academy of CASIC, Beijing 100854, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,9,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1049\/ip-rsn:20030743","article-title":"Analysis of micro-Doppler signatures","volume":"150","author":"Chen","year":"2003","journal-title":"IEEE Proc. 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