Design of Filtering Power Divider Based on LTCC with Double Folded Substrate Integrated Waveguide

In this paper, a double-folded substrate-integrated waveguide (DFSIW) filter power divider based on low-temperature co-fired ceramic (LTCC) technology is proposed. By stacking four DFSIW resonant cavities, the filter is operated at the center frequency of 26 GHz by using the TE<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">101</inf> main mode, and the energy coupling efficiency is improved by adjusting the size and position of the two coupling slots to reduce the insertion loss of the device. Meanwhile, by connecting the Wilkinson power divider with a metal through-hole in the uppermost resonant cavity, the energy is conducted from the filter unit to the power divider unit, thus realizing the function of filter power division. In addition, the isolation of the output is improved by loading isolation resistors at the two outputs of the power divider. In order to verify the design content, a filtered power divider operating at 26 GHz with a 3 dB relative bandwidth of 16.4% is designed and implemented in the high frequency structure simulation software HFSS.