Influence of the directional coupler’s parameters on the characteristics of Butler matrix 4×4. Visnyk NTUU KPI Seriia - Radiotekhnika Radioaparatobuduvannia, [S. l.], n. 57, p. 43–50, 2014. DOI: 10.20535/RADAP.2014.57.43-50. Disponível em: https://radap.kpi.ua/radiotechnique/article/view/783. Acesso em: 14 mar. 2025.