A 77 GHz Phased Array Antenna Based on Substrate-Integrated Waveguide

In this study, a 77 GHz phased array antenna based on substrate-integrated waveguide (SIW) is proposed. The proposed phased array antenna includes two columns of transmitting (TX) linear antenna arrays and two rows of receiving (RX) linear antenna arrays, which form a rectangular ring distribution. These TX and RX antennas are vertically polarized cavity antennas fed by SIW slots. Simulation results show that the TX antennas and RX antennas have good phased scanning capabilities of ±30° in the elevation direction and ±45° in the azimuth direction at 75–81 GHz, respectively. In order to verify the performance of the proposed antenna, we excite each one of the TX and RX linear phased array antennas using two SIW power dividers and two WR12 waveguide ports. The measured bandwidths of the TX and RX antenna arrays with voltage standing wave ratio less than 2 are 14.5% from 73.7 to 85 GHz and 13.7% from 72.5 to 83.2 GHz, respectively. The measured boresight gains of the TX and RX antenna arrays at the operating frequency band are around 12 and 11.5 dBi, respectively.