Design and implementation of DP-DQPSK DWDM transmission system by using direct detection. Periodicals of Engineering and Natural Sciences, [S. l.], v. 9, n. 4, p. 166–179, 2021. DOI: 10.21533/pen.v9.i4.936. Disponível em: https://pen.ius.edu.ba/index.php/pen/article/view/936. Acesso em: 23 aug. 2026.