A Compact Dual Linearly-Polarized Single-Plane Monopulse Antenna Array Based on SIW and Strip-Line Feed

A compact dual linearly polarized monopulse antenna array is proposed in this article. The size of the antenna array is
$3.13\lambda _{0} \times 4.38\lambda _{0}$
, and it consists of two comparators, multilayer coupling slots, and a group of
$4\times $
4 square patches. By using high-order-mode cavities and integrating the feeding network with the radiating part, the size of the antenna is considerably reduced. A prototype of the proposed antenna is fabricated and evaluated to the feasibility of the design. The measured total impedance bandwidth for four ports is 1.6% (18.65–18.95 GHz). The peak gains of the sum pattern with vertical and horizontal polarization are greater than 16.02 and 14.92 dBi, respectively. The null depths of the difference pattern at 18.8 GHz are less than −32 dB. The measurement results are in good agreement with the simulation results.