An ultra-wideband 1-D monopulse antenna based on tightly coupled dipole linear array

A low-profile and ultra-wideband (UWB) 1-D monopulse antenna based on the tightly coupled dipole linear array (TCDLA) is proposed in this paper. First, a compact UWB monopulse feeding network is discussed. It consists of a UWB monopulse comparator and a pair of miniaturized 1-to-4 power dividers with tapered baluns. Then, a TCDLA element with frequency selective surfaces (FSS) superstrates is designed for radiation. Meanwhile, the feeding network is arranged at the bottom layer to avoid spurious radiation on radiation patterns. Finally, by connecting the feeding network and radiation part, a UWB monopulse antenna prototype is fabricated and measured. The proposed monopulse antenna array achieved an 82.35% (5-12 GHz) shared bandwidth and the isolation is greater than 16 dB. The measured results are in good agreement with the simulated results.