{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T11:00:06Z","timestamp":1783335606950,"version":"3.54.6"},"reference-count":23,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,10,28]],"date-time":"2024-10-28T00:00:00Z","timestamp":1730073600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Korea Research Institute for defense Technology planning and advancement (KRIT)","award":["KRIT-CT-21-033"],"award-info":[{"award-number":["KRIT-CT-21-033"]}]},{"name":"Korea government (DAPA (Defense Acquisition Program Administration))","award":["KRIT-CT-21-033"],"award-info":[{"award-number":["KRIT-CT-21-033"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>The importance of information gathering is emphasized to minimize casualties and economic losses in warfare. Through electronic warfare, which utilizes electromagnetic waves, it is possible to discern the enemy\u2019s intentions and respond accordingly, thereby leading the battle advantageously. Consequently, related research is actively underway. The development of various radar signal modulation techniques has revealed limitations in the existing modulation recognition methods, necessitating the development of distinguishing features to overcome these limitations. This paper proposes and analyzes distinguishing features that can differentiate various modulation schemes. Eleven distinguishing features were employed, and twenty-two types of modulated signals, including analog, digital, and composite modulation, were classified using hierarchical classification approach and maximum likelihood estimation (MLE). The proposed method achieves a recognition performance of 99.76% at an SNR of 20 dB and 98.45% at an SNR of 8 dB.<\/jats:p>","DOI":"10.3390\/e26110915","type":"journal-article","created":{"date-parts":[[2024,10,28]],"date-time":"2024-10-28T11:52:47Z","timestamp":1730116367000},"page":"915","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["LPI Radar Waveform Recognition Based on Hierarchical Classification Approach and Maximum Likelihood Estimation"],"prefix":"10.3390","volume":"26","author":[{"given":"Kiwon","family":"Rhee","sequence":"first","affiliation":[{"name":"Department of Intelligent Semiconductors, Soongsil University, Seoul 06978, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jaeyoung","family":"Baik","sequence":"additional","affiliation":[{"name":"Department of Information and Communication, Soongsil University, Seoul 06978, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Changhoon","family":"Song","sequence":"additional","affiliation":[{"name":"EW AI & Jamming Technology R&D, LIG Nex1 Co., Ltd., Suwon 16347, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyun-Chool","family":"Shin","sequence":"additional","affiliation":[{"name":"Department of Intelligent Semiconductors, Soongsil University, Seoul 06978, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,28]]},"reference":[{"key":"ref_1","unstructured":"Adamy, D.L. 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