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This paper presents the effect of surface roughness on the performance of the 3D printed near field focused THz Cassegrain antenna configuration. It is found that the roughness affects the focal plane parameters. The nearfield directivity is reduced by ~ 3.5 dB for 60 µm rough surface, there is only a small effect on the focus spot width. A smoothing process, which reduces the conductive coating surface roughness to 4 µm, is also described. The roughness loss is less than 0.1 dB at 300GHz.
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Surface roughness impact of 3D Ti-alloy printed WR-10 waveguide and rectangular horn antenna at W-band (75-110 GHz)
Abstract To investigate the effect of the surface roughness of 3D-metal-printed sub-THz components, the WR-10 3-inch-long waveguide and 24 dBi rectangular horn antenna were 3D-metal-printed using a titanium alloy powder and a high-resolution 3D metal printer. The characterized surface roughness of the printed components was 17.27 µm in RMS from a 3D optical surface profiler, and a nodule ratio of 7.89 µm and surface ratio of 1.52 for Huray model from the analyzed SEM images. The measured results of the 3D-metal-printed waveguide and rectangular horn antenna were compared with the ones of commercial waveguide and horn antenna having the same shapes. The 3D-metal-printed waveguide has 4.02 dB higher loss than the commercial waveguide, which may be caused by an ohmic loss of 0.85 dB and a surface roughness loss of 2.81 dB. The 3D-metal-printed horn antenna has 2 dB higher loss then the commercial horn antenna, which may be caused by an ohmic loss of 0.2 dB, surface roughness of 0.1 dB and fabrication tolerance loss of 1.7 dB. The loss separation was done from the EM simulation by changing the conductor material and surface roughness.
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- Award ID(s):
- 2029086
- PAR ID:
- 10570912
- Publisher / Repository:
- Springer Micro and Nano Systems Letters
- Date Published:
- Journal Name:
- Micro and Nano Systems Letters
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2213-9621
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1186/s40486-024-00220-2
