A Compact Quasi-Elliptic Dual-Mode Cavity Filter Using LTCC Technology for V-band WLAN Gigabit Wireless Systems

In this paper, the development of highly integrated dual-mode filter solutions is presented for V-band compact, low-cost wireless front-end modules utilizing multilayer low temperature cofired ceramic (LTCC) technologies. A dual-mode cavity filter experimentally demonstrates a quasi-elliptic response and excellent performance in terms of low insertion loss ( < 2.76 dB) and high rejection. The rectangular shaped cavity resonator is first designed to generate two resonant modes (TE₁₀₂ and TE₂₀₁) that are orthogonal each other. Then, the location of the feeding structures and the size of the external slots are optimized to generate the quasi-elliptic dual-mode response. The filter has been implemented by employing rows of vias as sidewalls represent a new class of devices that enable the three dimensional (3D) integration for V-band WLAN gigabit wireless systems