Wideband $W$ -Band Substrate-Integrated Waveguide Magnetoelectric (ME) Dipole Array Antenna

In this communication, a W-band substrate-integrated waveguide (SIW) magnetoelectric (ME) dipole array antenna is reported with a wide operating bandwidth. By combing a longitudinal slot, which is functioned as a magneto dipole, on the top surface of the SIW, and a loaded short-circuited patch functioned as an electric dipole, an SIW ME dipole is designed. Thus, both merits of the low-loss character of the SIW and the wideband performance of the ME dipole are utilized. The proposed technique is capable of designing a large planar array with a wide operating bandwidth. As a demonstration, a W-band $4\times 8$ SIW array antenna is designed and fabricated by using a low-cost printed circuit board technology. The experimental results show that the 10 dB impedance bandwidth of the designed prototype is 13.89%, i.e., from 78.4 to 90.1 GHz. Stable radiation patterns, high radiation efficiencies, and low cross-polarization levels are achieved within a wide operating frequency band. In addition, a stable gain of 19.6±0.7 dBi is obtained as well. The proposed antenna is a good candidate for the millimeter-wave wireless system.