Waveguide orthogonal mode converter for antenna feed system

The utility model discloses a waveguide orthogonal mode converter for an antenna feed system. The waveguide orthogonal mode converter comprises an impedance converter (1), a main arm (2), a coupling branch A (3), a coupling branch B (4), a diaphragm (7), a tuning screw (8), an asynchronous coupling window (5) and a triangular wedge bulge structure (6). According to the waveguide orthogonal mode converter, by virtue of the asynchronous coupling window (5) and the triangular wedge bulge structure (6) at the top of the asynchronous coupling window (5), a reflection coefficient between the coupling branch B (4) and the main arm (2) is effectively improved, and the signal passing capability is improved; and meanwhile, a high isolation degree between the coupling branch A (3) and the coupling branch B (4) is kept, so that signal crosstalk between the two coupling branches is effectively avoided, and the whole performance of the orthogonal mode converter is improved.