W -Band High-Gain Substrate Integrated Cavity Antenna Array on LTCC

A 4 × 4 high-gain substrate integrated cavity (SIC) antenna array using multilayered low-temperature cofired ceramic (LTCC) technology is proposed and designed for W-band applications. The TM211 mode of the SIC is utilized. Two parasitic patches are introduced on the top surface of the SIC to adjust the aperture electromagnetic field distribution of the TM211 mode in the cavity for obtaining a high-gain broadside radiation pattern. A bow tie shape is adopted for the parasitic patches to improve the matching characteristic of the SIC. The SIC is modified to a stepped flared shape to improve the gain characteristic of the antenna element. Subsequently, a two-layer low-loss substrate integrated waveguide (SIW) feeding network is designed for the 4 × 4 antenna array on the basis of the proposed high-gain SIC radiating element. The proposed antenna array shows a wide measured bandwidth of 17.48% from 81.45 to 97.05 GHz at |S11| <; -10 dB and a measured gain of up to 20.3 dBi.