3D Printed PLA-based SIW Bandpass Filter with Artificial Dielectric Material

It is well-known that filter is an essential component in wireless communication systems. Recently the development of wireless communication systems requires a compact and lightweight device. Therefore, in this paper, the structures of substrate integrated waveguide (SIW) and artificial dielectric material (ADM) are proposed for the development of compact and lightweight bandpass filter. The utilization of SIW structure can minimize losses at high frequencies while reducing the dimension. Whilst, the involvement of ADM structure can reduce the dimension of radio frequency (RF) device without deteriorating its performance. However, the combination of these two structures can increase the complexity of fabrication process, as well as the weight of filter significantly. Therefore, a 3D printing technology can be considered as a means in the fabrication process of SIW bandpass filter with ADM. Furthermore, the use of 3D printing technology with polylactic acid (PLA) as a filament can also reduce the weight of filter. It is noted that PLA is a lightweight material and widely used in 3D printing technology. After fabrication and coating process with high conductivity paint, the prototype of 3D printed PLA-based SIW bandpass filter with ADM is characterized experimentally. The characterization results show that the prototype can operate at multiple frequency bands with the center frequencies of 2.71 GHz, 3.835 GHz, 5.14 GHz, and 7.615 GHz, and the bandwidth responses of 0.27 GHz, 0.675 GHz, 1.25 GHz, and 0.63 GHz, respectively.