Design of a coaxial radiation feeder structure applied to dual-band feed

A novel dual-band feeder is investigated. The structure converts two TM01 modes from two separate non-coaxial microwave sources effectively, and coaxial radiation has been achieved. A dual-bend circular waveguide mode converter is designed with parallel axes of both input and output ports, realizing the conversion from TM10 to TE11 circular waveguide mode at high band. Another mode converter is designed to realize axes superposition of different radiation systems and mode conversion from TM011 to TE11 coaxial waveguide mode based on intermediate TE10 rectangular waveguide mode at low band. Simulations have verified the design.