This paper introduces a four-way power combiner operating in the 94 GHz millimeter-wave based on spatial power combining technology. The four millimeter-waves with Gaussian beams are combined in the waveguide, increasing the output power. The combiner is composed of five circular waveguides connected by four long and narrow coupling slots. Four sub-waveguides are separately connected to four input ports and one main waveguide is connected to a common output port. The TE₁₁-mode is used as the input mode, which has two vertical and horizontal polarization directions. Four sub-waveguides are respectively input corresponding to polarization directions TE₁₁-wave with Gaussian beams. The power of TE₁₁-wave is transmitted to the main waveguide by the coupling slots, combined in the main waveguide, and output with the common port. We analyze the combiner and verify the availability of the design structure by numerical stimulation with CST MWS (Microwave Studio) software. The power-combining efficiency can be over 97%, and the output beams remain Gaussian beams with nearly fourfold increased power. The proposed model provides technological approaches for power combiner application in millimeter-wave.

The terahertz (THz) rotation mirror imaging system is an alternative to the THz array imaging system. A THz rotation mirror imaging system costs less than a THz array imaging system, while the imaging speed of a THz rotation mirror imaging system is much higher than the imaging speed of a THz raster-scan imaging system under the same hardware conditions. However, there is some distortion in the THz image from the THz rotation mirror imaging system. The distortion, which makes images from the THz rotation mirror imaging system difficult to identify, results from the imaging principle of the THz rotation mirror imaging system. In this article, a method based on the scale-recurrent network (SRN) is put in place to correct the distortion. A comparison between distorted THz images and corrected images shows that the proposed method significantly increases the structural similarity between the THz images and the samples.