Fig. 1. Comparison of conventional filter with rectangular insert and novel filter with triangular insert

Fig. 2. Structure of the diplexer

Fig. 3. Equivalent impedance matching network of a bandpass filter

Fig. 4. Frequency response of the waveguide bend

Fig. 5. Frequency response of the filter when l and w change

Fig. 6. Frequency responses of two filters with central frequencies of 9.15 GHz and 9.75 GHz

Fig. 7. Simulation model of the diplexer

Fig. 8. Simulated frequency response of the diplexer

Fig. 9. Electric field distribution of the diplexer

Fig. 10. Photo of the diplexer

Fig. 11. Photo of the diplexer test

Fig. 12. Frequency response of the diplexer