Ka-band Rectangular Waveguide to HMSIW Transition Based on Trapezoidal-shaped Probe

Abstract

In this letter, a novel rectangular waveguide-to-half mode substrate integrated waveguide (HMSIW) transition is presented. The transition is realized by using a trapezoidal-shaped probe to terminate the TE10 mode of the standard waveguide within a wide frequency band. A back-to-back transition at Ka-band is designed and fabricated. The simulated results show that the proposed structure has less than 0.35 dB insertion loss and a better than 20 dB return loss within a frequency range from 25 to 40 GHz for a back-to-back structure. In addition, there is no need of intermediate transition for this design. The size of the proposed transition is reduced by approximately 81.8 % as compared with the Waveguide-to-HMSIW transition using antipodal fin-line. The proposed transition has the advantages of compact size and sample structure, and it is suitable for the application of HMSIW technology.