A low-loss and compact single-layer butler matrix for a 5G base station antenna. - Idrus, Intan Izafina; Abdul Latef, Tarik; Aridas, Narendra Kumar; Abu Talip, Mohamad Sofian; Yamada, Yoshihide; Abd Rahman, Tharek; Adam, Ismahayati; Mohd Yasin, Mohd Najib (PLoS ONE, 2019)