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Additionally, many chaotic signals lack desirable features for certain sensor applications, such as radar imaging. For instance, these signals introduce large, undesirable ambiguities with a broad mainlobe width and high sidelobe levels, which limit radar sensing capabilities. In this work, we show that a reservoir computer, combined with a nonlinear optimization procedure, can be used to design signals with targeted features. As an example, we consider a high-dimensional R\u00f6ssler chaotic system and optimize it to reduce the mainlobe width and minimize sidelobes, thereby improving radar detection.<\/jats:p>","DOI":"10.1063\/5.0320699","type":"journal-article","created":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T12:58:47Z","timestamp":1780923527000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["Harnessing chaotic dynamics with optimized reservoir computer"],"prefix":"10.1063","volume":"36","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9901-133X","authenticated-orcid":false,"given":"Chandra S.","family":"Pappu","sequence":"first","affiliation":[{"name":"Electrical, Computer and Biomedical Engineering, Union College 1 , Schenectady, NY,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2371-2049","authenticated-orcid":false,"given":"Thomas L.","family":"Carroll","sequence":"additional","affiliation":[{"name":"Retired from U.S. Naval Research Lab 2 , Washington, D.C.,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2026,6,8]]},"reference":[{"key":"2026060808584097900_c1","doi-asserted-by":"publisher","first-page":"R647","DOI":"10.1103\/PhysRevE.50.R647","volume":"50","year":"1994","journal-title":"Phys. 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