{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,28]],"date-time":"2025-10-28T18:43:24Z","timestamp":1761677004338,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,5,18]],"date-time":"2021-05-18T00:00:00Z","timestamp":1621296000000},"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":"publisher","award":["61901514"],"award-info":[{"award-number":["61901514"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Young Talent Program of Early Warning Academy","award":["TJRC425311G11"],"award-info":[{"award-number":["TJRC425311G11"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>As a special micro-motion feature of rotor target, rotational angular velocity can provide a discriminant basis for target classification and recognition. In this paper, the authors focus on an efficient rotational angular velocity estimation method of the rotor target is based on the combination of the time\u2013frequency analysis algorithm and Hough transform. In order to avoid the problems of low time\u2013frequency resolution and cross-term interference in short-time Fourier transform and Wigner\u2013Ville distribution algorithm, a modified short-time fractional Fourier transform (M-STFRFT) is proposed to obtain the time-FRFT domain (FRFD)-frequency spectrum with the highest time\u2013FRFD\u2013frequency resolution. In particular, an orthogonal matching pursuit (OMP)-based algorithm is proposed to reduce the computational complexity when estimating the matched transform order in the proposed M-STFRFT algorithm. Firstly, partial transform order candidates are selected randomly from the complete candidates. Then, a partial entropy vector corresponding to partial transform order candidates is calculated from the FRFT results and utilized to reconstruct the complete entropy vector via the OMP algorithm, and the matched transform order can be estimated by searching minimum entropy. Based on the estimated matched transform order, STFRFT is performed to obtain the time\u2013FRFD\u2013frequency spectrum. Moreover, Hough transform is employed to obtain the energy accumulation spectrum, and the micro-Doppler parameter of rotational angular velocity can be estimated by searching the peak value from the energy accumulation spectrum. Both simulated data and measured data collected by frequency modulated continuous wave radar validate the effectiveness of the proposed algorithm.<\/jats:p>","DOI":"10.3390\/rs13101970","type":"journal-article","created":{"date-parts":[[2021,5,18]],"date-time":"2021-05-18T12:17:16Z","timestamp":1621340236000},"page":"1970","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Efficient Rotational Angular Velocity Estimation of Rotor Target via Modified Short-Time Fractional Fourier Transform"],"prefix":"10.3390","volume":"13","author":[{"given":"Wantian","family":"Wang","sequence":"first","affiliation":[{"name":"Early Warning Academy, Wuhan 430019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yong","family":"Zhu","sequence":"additional","affiliation":[{"name":"Early Warning Academy, Wuhan 430019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ziyue","family":"Tang","sequence":"additional","affiliation":[{"name":"Early Warning Academy, Wuhan 430019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1841-598X","authenticated-orcid":false,"given":"Yichang","family":"Chen","sequence":"additional","affiliation":[{"name":"Early Warning Academy, Wuhan 430019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhenbo","family":"Zhu","sequence":"additional","affiliation":[{"name":"Early Warning Academy, Wuhan 430019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongjian","family":"Sun","sequence":"additional","affiliation":[{"name":"Early Warning Academy, Wuhan 430019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chang","family":"Zhou","sequence":"additional","affiliation":[{"name":"Early Warning Academy, Wuhan 430019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1109\/TAES.2006.1603402","article-title":"Micro-Doppler effect in radar: Phenomenon, model and simulation study","volume":"42","author":"Chen","year":"2006","journal-title":"IEEE Trans. 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