Single-Layer 2-D SIW monopulse slot antenna array with dual-mode comparator

A single-layer 2-D substrate integrated waveguide (SIW) monopulse slot antenna is proposed in this paper. By adopting the dual-mode monopulse comparators (DMCs), the feeding network exhibited excellent amplitude -phase consistency and high isolations between input ports. Additionally, the structure of the proposed an-tenna is effectively simplified by integrating the feeding network with the radiation part on a single-layer sub-strate. Based on it, a monopulse antenna prototype is fabricated and measured. The measured results show that the-10 dB shared impedance bandwidth of 4 ports is 2.05 % (9.65-9.85 GHz) and the isolations between ports are better than 25 dB. The measured gain of the sum pattern is 13.93 dBi at 9.75 GHz, and the null depths of the difference patterns are lower than-30 dB.