W-Band Waveguide Bandpass Filters Fabricated by Micro Laser Sintering

This paper presents a fifth-order W-band waveguide bandpass filter with a Chebyshev response, operating at center frequency of 90 GHz and having fractional bandwidth of 11%. The filter is fabricated by micro laser sintering process which is a powder bed based additive manufacturing technology. Use of this technology allows the filter to be made accurately with high resolution and good surface quality in one piece. This results in better performance in term of insertion loss and reproducibility. For the purpose of comparison, two similar filters are presented in this paper with the same structure and specification, one made from stainless steel and the other made from stainless steel coated with copper. Both filters are tested and have excellent agreement between measurements and simulations.