Shorted Trapezoidal SIW Antenna With Quasi-Hemispherical Pattern for 2D Wide Scanning Planar Phased Array Antenna

This communication presents a shorted trapezoidal substrate integrated waveguide (SIW) antenna with a quasi-hemispherical pattern composed of a 64-element (8 $\times $ 8) 2-D planar phased array. The proposed low-profile SIW antenna is analyzed in terms of resonating mode and magnetic current and is simulated. The proposed antenna is composed of a trapezoidal patch and shorting vias. The upper side of the trapezoid is the shorting wall, and the middle of the bottom side provides shorting with a via. The resonance produced by the structure causes the magnetic currents to have three different directions. Hence, the single element has a quasi-hemispherical beam pattern on a large ground. The 64-element (8 $\times $ 8) 2-D planar phased array was implemented and measured. Because the constituent elements have a quasi-hemispherical pattern, the phased array antenna has a wide scanning range in all azimuth directions. The measured scanning range with 5 dB gain fluctuation in the $\phi = 0^\circ $ plane, $\phi = 45^\circ $ plane, and $\phi = 90^\circ $ plane are 170°, 143°, and 168°, respectively.