Dual Mode Monopulse Conical Horn Antenna for 5G Millimeter-Wave band Applications

A dual mode monopulse network at K-band is presented for 5G space applications. This network consists of two mode converters from rectangular to circular waveguide. The first converter excites the $TE_{11}^{cir}$ mode and the second excites the $TE_{01}^{cir}$ mode in a circular waveguide, both from the $TE_{10}^{rec}$ mode of nominal WR-28 rectangular waveguide sections. This mode converter network is then integrated into a conical horn antenna to radiate the sum and difference patterns associated to each excited mode inside its feeding circular waveguide. This integration process is detailed to properly avoid the propagation of other higher order modes as well as mode mutual coupling. The simulated results such as reflection coefficient associated to each part of the design, pattern and directivity of final structure are presented. The monopulse antenna system provides up to ±11° range per beam in the angular of arrival detection of 5G satellite applications at millimeter-wave band for high data rate operation.