A new type of the air‐filled substrate integrated gap waveguide resonator

Abstract

This article presents the design and analysis of an air‐filled substrate integrated gap waveguide (ASIGW) resonator. The electromagnetic field of each resonant mode in the resonator is studied by theoretical modeling and EM simulation. Besides, the relationship between the dimensions and Qu is analyzed and the Qu of the resonator can be as high as 2080 at Ku band. Compared with conventional rectangular waveguide resonator and gap waveguide (GW) resonator, the proposed ASIGW resonator can be fabricated more easily. Compared with the substrate integrated waveguide resonator, the ASIGW resonator is more tolerant with dimensional errors and with less degenerate modes. As an example, a fifth‐order band‐pass filter based on the ASIGW resonators is presented to verify the previous conclusions.

A 3D printed bullet‐shaped filter based on zero‐gap circular waveguide cavities

“…For example, Fangfang Fan proposed the half-height GW pins in References [10,11] to reduce the fabrication difficulty which eases the situation, and the glide-symmetric holy GW structures given by Mahsa Ebrahimpouri in References [13][14][15] replace the long and thin pins with glide-symmetric holes, but unfortunately, the loss is much higher than conventional ones. On the other hand, our former paper 12 shows that a considerable deterioration can be produced due to the air gap variation. Moreover, the zero-gap waveguide pin is proposed by Abbas Vosoogh in Reference [16] in which the air gap is reduced to almost zero to achieve flexible mechanical assembly meanwhile the stopband characteristics are maintained.…”

“…8 The sidewall of the GW is a bed of pins, and the GW pins are in the forms of square, cylindrical, or conical pins 8,9 (the mushroom type of pins in the inverted microstrip gap waveguide and substrate-integrated gap waveguide are not included since the dielectric loss can be considerable). However, there are two primary obstacles for engineering applications: the first one is that the long and thin GW pins are easy to be broken in fabrication, transportation, and post-processing 10,11 ; The other reason is that the performances of the resonating components based on the GW are so sensitive to the air gap variation 12 that expansive and complicated post-processing procedures are required to obtain highly accurate air gap and reasonable performance with the design specifications. Besides, a highly accurate assembly process is required, too.…”