{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T04:46:04Z","timestamp":1792644364377,"version":"4.5.0"},"reference-count":39,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,2,11]],"date-time":"2025-02-11T00:00:00Z","timestamp":1739232000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"\u201cPioneer\u201d and \u201cLeading Goose\u201d R&amp;D Program of Zhejiang Province","award":["2023C01148"],"award-info":[{"award-number":["2023C01148"]}]},{"name":"\u201cPioneer\u201d and \u201cLeading Goose\u201d R&amp;D Program of Zhejiang Province","award":["TD2022006"],"award-info":[{"award-number":["TD2022006"]}]},{"name":"Hangzhou Leading Innovation and Entrepreneurship Team","award":["2023C01148"],"award-info":[{"award-number":["2023C01148"]}]},{"name":"Hangzhou Leading Innovation and Entrepreneurship Team","award":["TD2022006"],"award-info":[{"award-number":["TD2022006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we present a low-cost, low-power millimeter-wave (mmWave) skeletal joint localization system. High-quality point cloud data are generated using the self-developed BHYY_MMW6044 59\u201364 GHz mmWave radar device. A sliding window mechanism is introduced to extend the single-frame point cloud into multi-frame time-series data, enabling the full utilization of temporal information. This is combined with convolutional neural networks (CNNs) for spatial feature extraction and a bidirectional gated recurrent unit (BiGRU) for temporal modeling. The proposed spatio-temporal information fusion framework for multi-frame point cloud data fully exploits spatio-temporal features, effectively alleviates the sparsity issue of radar point clouds, and significantly enhances the accuracy and robustness of pose estimation. Experimental results demonstrate that the proposed system accurately detects 25 skeletal joints, particularly improving the positioning accuracy of fine joints, such as the wrist, thumb, and fingertip, highlighting its potential for widespread application in human\u2013computer interaction, intelligent monitoring, and motion analysis.<\/jats:p>","DOI":"10.3390\/s25041070","type":"journal-article","created":{"date-parts":[[2025,2,11]],"date-time":"2025-02-11T05:34:32Z","timestamp":1739252072000},"page":"1070","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["A Sliding Window-Based CNN-BiGRU Approach for Human Skeletal Pose Estimation Using mmWave Radar"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-4437-3777","authenticated-orcid":false,"given":"Yuquan","family":"Luo","sequence":"first","affiliation":[{"name":"School of Electronic Information Engineering, Beihang University, Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-5250-772X","authenticated-orcid":false,"given":"Yuqiang","family":"He","sequence":"additional","affiliation":[{"name":"School of Electronic Information Engineering, Beihang University, Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8112-8756","authenticated-orcid":false,"given":"Yaxin","family":"Li","sequence":"additional","affiliation":[{"name":"Hangzhou Innovation Institute of Beihang University, Hangzhou 310052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huaiqiang","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Electronic Information Engineering, Beihang University, Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Electronic Information Engineering, Beihang University, Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1489-0812","authenticated-orcid":false,"given":"Fei","family":"Gao","sequence":"additional","affiliation":[{"name":"School of Electronic Information Engineering, Beihang University, Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Moreira, R., Teixeira, S., Fialho, R., Miranda, A., Lima, L.D.B., Carvalho, M.B., Alves, A.B., Bastos, V.H.V., and Teles, A.S. 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