{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T11:07:07Z","timestamp":1790075227913,"version":"4.0.1"},"reference-count":35,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T00:00:00Z","timestamp":1790035200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Reliable AI-assisted interpretation of radar-derived micro-Doppler images requires evaluation protocols that separate image-archive regularities from physical generalization. We audited 4849 DIAT-\u03bcSAT JPEG spectrograms and evaluated partition sensitivity, image controls, and representation-randomized training. Raw radar recordings and acquisition metadata were unavailable. A post hoc feature audit found within-class continuity in filename order and a measurable shift between early training and late test blocks in all six classes, using both frozen ResNet18 and HOG features; the source of this order structure remains unknown. Frozen ResNet18 balanced accuracy decreased from 97.71% under a random split to 88.64% under the class-stratified, late-index S3 split. Boundary-restricted images retained class information but did not identify a non-physical artifact or prove shortcut learning. Native JPEG file attributes were separately class-associated but were not supplied to the image classifiers. In a confirmatory long-budget comparison with ten paired optimization seeds and matched checkpoint selection, representation-randomized F2 exceeded the ColorJitter-plus-RandomGrayscale A3WC comparator by 1.69 percentage points in mean seed-wise worst-case balanced accuracy over the protocol-defined K0\/K1\/K3\/K4 rendering set (seed-bootstrap 95% interval +0.45 to +2.78; exact two-sided sign-flip p = 0.0352). F2 did not improve the held-out K2 rendering stress test. The results establish an image-level archive-order evaluation stress and a limited finite-rendering training benefit, not acquisition-independent radar recognition.<\/jats:p>","DOI":"10.3390\/s26195989","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T10:21:48Z","timestamp":1790072508000},"page":"5989","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Assessing the Reliability of Micro-Doppler Spectrogram Classification from the DIAT-\u03bcSAT JPEG Archive"],"prefix":"10.3390","volume":"26","author":[{"given":"Mert","family":"Karahan","sequence":"first","affiliation":[{"name":"Department of Electronics and Communication Engineering, Turkish Military Academy, National Defence University, 06420 Ankara, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]},{"given":"\u015eevki Gani","family":"\u015eanl\u0131\u00f6z","sequence":"additional","affiliation":[{"name":"Faculty of Engineering and Natural Sciences, Istanbul Atlas University, 34408 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,22]]},"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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