The further investigation of the true time delay unit based on discrete fiber Bragg gratings

► Phased array antenna (PAA) system based on true time delay (TTD) unit is studied. ► The TTD unit is constructed by discrete fiber Bragg gratings (FBGs). ► Far field pattern of such a PAA system is analyzed by interference theory. ► Pattern is independent of the neighboring grating distance in the first fiber. ► The TTD unit based on discrete FBGs can provide high resolution time delay.