A Rectangular Waveguide Filter With Integrated E-Plane Probe Transition

A novel Rectangular waveguide (RWG) filter with integrated transitions is proposed in this letter. The E-plane probe transition, which is employed to couple the energy from the RWG resonator to the microstrip line (MSL), is used as the external coupling mechanism. The integrated design of the filter and transition can reduce the design complexity and size of the circuit. In order to verify the design, a prototype of the filter is fabricated and measured. It provides an in-band return loss and insertion loss of better than 14.6 and 1.5 dB, respectively, in the frequency range of 8.39 to 8.85 GHz.