Double-frequency duplexer based on substrate integrated waveguide

The invention discloses a double-frequency duplexer based on a substrate integrated waveguide. The double-frequency duplexer comprises a filter dielectric substrate, a top metal layer arranged on theupper surface of the filter dielectric substrate, a bottom metal layer arranged on the lower surface of the filter dielectric substrate, and a metal layer arranged between the upper surface of the filter dielectric substrate and the lower surface of the filter dielectric substrate; T-shaped output ports are formed in the metal layers on the upper surface and the lower surface of the filter mediumsubstrate; and an input feed network is arranged on the middle metal layer. The double-frequency duplexer is simple in design structure and easy for industrial processing; firstly a miniaturized double-frequency SIW-based double-frequency duplexer is introduced, so that the problem of relatively large size of a filter is solved to a relatively great extent; and secondly, the input feed network structure of the middle metal layer is introduced, so that the gain based on the SIW filter is further increased, and a foundation is laid for improvement of the passband gain of the double-frequency SIWfilter and improvement of the echo loss.