Antenna Design for Ultra-Wideband System Using a Fractal H-Shaped Structure for Enhanced Filtering and Narrowband Operation. Al-Nahrain Journal for Engineering Sciences, [S. l.], v. 28, n. 4, p. 515–523, 2025. DOI: 10.29194/NJES.28040515. Disponível em: https://nahje.journalpath.com/nahje/article/view/2. Acesso em: 11 apr. 2026.