{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T15:58:01Z","timestamp":1792079881242,"version":"4.4.0"},"reference-count":28,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T00:00:00Z","timestamp":1789516800000},"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":["52577014"],"award-info":[{"award-number":["52577014"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52577013"],"award-info":[{"award-number":["52577013"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["52577014"],"award-info":[{"award-number":["52577014"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["52577013"],"award-info":[{"award-number":["52577013"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"National Key Laboratory of Electromagnetic Information Control and Effects","award":["20240104"],"award-info":[{"award-number":["20240104"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Microwave imaging is promising for non-contact inspection of radar-absorbing materials (RAMs); however, strong structured non-damage responses in reconstructed microwave images can resemble surface defects and trigger false detections, while hard masking may remove weak damage responses near ambiguous boundaries. To address these issues, this paper proposes dual-channel scale-adaptive clutter suppression with confidence-derived gating as an application-specific front end for surface-damage detection in curved RAM specimens. A normalized microwave-response map and a fixed morphology-enhanced map, both deterministically derived from the same measurement, are jointly encoded. The input-conditioned scale-adaptive pyramid-pooling module (SA-PPM) reweights multi-scale context branches, while confidence-derived adaptive-threshold gating (C-ATG) generates a bounded pixel-wise threshold from the retention confidence and its ambiguity proxy. Continuous-weight filtering (CW-FI) then produces continuous retention weights, enabling gradual attenuation instead of forced binary removal. Experiments were conducted on a paired visible-light\/microwave RAM dataset. On the held-out test subset, the method achieved pixel-level discrimination between clutter and retained responses and improved detection of strip-like cracks and circular spalling under matched detector-side settings.<\/jats:p>","DOI":"10.3390\/s26185854","type":"journal-article","created":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T07:58:59Z","timestamp":1789545539000},"page":"5854","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Dual-Channel Scale-Adaptive Clutter Suppression with Confidence-Derived Gating for Microwave Inspection of Curved Radar-Absorbing Materials"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-7004-4968","authenticated-orcid":false,"given":"Yang","family":"Fang","sequence":"first","affiliation":[{"name":"State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Research Center of NDT and Structural Integrity Evaluation, School of Aerospace Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-6820-6936","authenticated-orcid":false,"given":"Jiaqi","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Research Center of NDT and Structural Integrity Evaluation, School of Aerospace Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-6970-4233","authenticated-orcid":false,"given":"Wei","family":"Cui","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Electromagnetic Information Control and Effects, Shenyang 110037, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6119-1400","authenticated-orcid":false,"given":"Xiaolong","family":"Wei","sequence":"additional","affiliation":[{"name":"Science and Technology on Plasma Dynamics Laboratory, Air Force Engineering University, Xi\u2019an 710000, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Bin","family":"Liu","sequence":"additional","affiliation":[{"name":"Shaanxi Special Equipment Inspection and Research Institute, Xi\u2019an 710049, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"software","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4257-2771","authenticated-orcid":false,"given":"Yong","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Research Center of NDT and Structural Integrity Evaluation, School of Aerospace Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3203-4320","authenticated-orcid":false,"given":"Zhenmao","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Engineering Research Center of NDT and Structural Integrity Evaluation, School of Aerospace Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2303104","DOI":"10.1002\/advs.202303104","article-title":"Carbon-Based Radar Absorbing Materials toward Stealth Technologies","volume":"10","author":"Kim","year":"2023","journal-title":"Adv. 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