{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T09:41:14Z","timestamp":1767865274483,"version":"3.49.0"},"reference-count":32,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,5,15]],"date-time":"2022-05-15T00:00:00Z","timestamp":1652572800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)","award":["287022738 TRR 196"],"award-info":[{"award-number":["287022738 TRR 196"]}]},{"name":"University of Duisburg-Essen","award":["287022738 TRR 196"],"award-info":[{"award-number":["287022738 TRR 196"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Synthetic aperture radar (SAR) at the terahertz (THz) spectrum has emerging short-range applications. In comparison to the microwave spectrum, the THz spectrum is limited in propagation range but benefits from high spatial resolution. The THz SAR is of significant interest for several applications which necessitate the mapping of indoor environments to support various endeavors such as rescue missions, map-assisted wireless communications, and household robotics. This paper addresses the augmentation of the high-resolution indoor mapped environment for object recognition, which includes detection, localization, and classification. Indoor object recognition is currently dominated by the usage of optical and infrared (IR) systems. However, it is not widely explored by radar technologies due to the limited spatial resolution at the most commonly used microwave frequencies. However, the THz spectrum provides a new paradigm of possible adaptation of object recognition in the radar domain by providing image quality in good compliance to optical\/IR systems. In this paper, a multi-object indoor environment is foremost mapped at the THz spectrum ranging from 325 to 500 GHz in order to investigate the imaging in highly scattered environments and accordingly create a foundation for detection, localization, and classification. Furthermore, the extraction and clustering of features of the mapped environment are conducted for object detection and localization. Finally, the classification of detected objects is addressed with a supervised machine learning-based support vector machine (SVM) model.<\/jats:p>","DOI":"10.3390\/s22103762","type":"journal-article","created":{"date-parts":[[2022,5,15]],"date-time":"2022-05-15T09:48:22Z","timestamp":1652608102000},"page":"3762","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Object Recognition in High-Resolution Indoor THz SAR Mapped Environment"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4526-8081","authenticated-orcid":false,"given":"Aman","family":"Batra","sequence":"first","affiliation":[{"name":"Institute of Digital Signal Processing, Universit\u00e4t Duisburg-Essen, 47057 Duisburg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4112-5988","authenticated-orcid":false,"given":"Fawad","family":"Sheikh","sequence":"additional","affiliation":[{"name":"Institute of Digital Signal Processing, Universit\u00e4t Duisburg-Essen, 47057 Duisburg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1422-7244","authenticated-orcid":false,"given":"Maher","family":"Khaliel","sequence":"additional","affiliation":[{"name":"Institute of Digital Signal Processing, Universit\u00e4t Duisburg-Essen, 47057 Duisburg, Germany"},{"name":"Benha Faculty of Engineering, Benha University, Benha 13511, Egypt"}]},{"given":"Michael","family":"Wiemeler","sequence":"additional","affiliation":[{"name":"Institute of Digital Signal Processing, Universit\u00e4t Duisburg-Essen, 47057 Duisburg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2571-8441","authenticated-orcid":false,"given":"Diana","family":"G\u00f6hringer","sequence":"additional","affiliation":[{"name":"Chair of Adaptive Dynamic Systems, Technische Universit\u00e4t Dresden, 01069 Dresden, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9679-5968","authenticated-orcid":false,"given":"Thomas","family":"Kaiser","sequence":"additional","affiliation":[{"name":"Institute of Digital Signal Processing, Universit\u00e4t Duisburg-Essen, 47057 Duisburg, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"29","DOI":"10.3389\/frobt.2015.00029","article-title":"Object Detection: Current and Future Directions","volume":"2","author":"Verschae","year":"2015","journal-title":"Front. 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