{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T18:01:21Z","timestamp":1784916081463,"version":"3.55.0"},"reference-count":25,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T00:00:00Z","timestamp":1784851200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"\n This work presents a compact planar four-way\n Gysel<\/jats:italic>\n power divider\/combiner designed for kilowatt-class coherent power combining in L-band pulsed radar transmitters. Unlike previously reported waveguide and coaxial Gysel architectures, the proposed planar implementation achieves a 3 kW peak output on an RO4003C substrate while maintaining low-loss, highly manufacturable microstrip construction. A power-aware full-wave electromagnetic optimization framework is introduced to refine characteristic impedances and electrical lengths, explicitly accounting for current distribution, thermal dissipation, and fabrication tolerance sensitivity, resulting in improved mid-band isolation and stable high-power performance. The fabricated prototype achieves an input return loss better than 15 dB, inter-port isolation exceeding 25 dB, amplitude imbalance within\n \n \n \n \n \n \u00b1<\/mml:mo>\n 0.3<\/mml:mn>\n \u00a0<\/mml:mi>\n \n d<\/mml:mi>\n B<\/mml:mi>\n <\/mml:mrow>\n <\/mml:mrow>\n <\/mml:math>\n <\/jats:alternatives>\n <\/jats:inline-formula>\n , and phase deviation within\n \n \n \n \n \n \u00b1<\/mml:mo>\n \n 1<\/mml:mn>\n \n \u2218<\/mml:mo>\n <\/mml:mrow>\n <\/mml:msup>\n <\/mml:mrow>\n <\/mml:math>\n <\/jats:alternatives>\n <\/jats:inline-formula>\n across 1.2\u20131.4 GHz. Grounded isolation branches equipped with flange-mounted high-power resistors, together with thermally optimized via arrays, ensure efficient dissipation of odd-mode energy under mismatch conditions. Experimental validation shows close agreement with simulation results, demonstrating that the proposed design represents a rare example of a planar microstrip Gysel combiner experimentally validated for reliable kilowatt-class operation in L-band solid-state radar systems, achieving a practical balance between power handling, compactness, and manufacturability.\n <\/jats:p>","DOI":"10.1371\/journal.pone.0354086","type":"journal-article","created":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T17:21:46Z","timestamp":1784913706000},"page":"e0354086","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Kilowatt-class planar four-way gysel combiner with power-aware impedance optimization for L-band pulsed radar"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-1987-9189","authenticated-orcid":true,"given":"Mohamed","family":"Mowafy","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mahmoud A.","family":"Shawky","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4722-1786","authenticated-orcid":true,"given":"Syed Tariq","family":"Shah","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdelhamid A.","family":"Shaalan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Safaa","family":"Ibrahim","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mai F.","family":"Ahmed","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,7,24]]},"reference":[{"key":"pone.0354086.ref001","doi-asserted-by":"crossref","unstructured":"Gysel UH. 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