• A compact 3D-printed dual-band dual-polarized gap waveguide slot antenna array is designed for Ku-band satellite communications, covering both Tx (14.0–14.5 GHz) and Rx (12.25–12.75 GHz) bands.
• Two stacked GWGs excite quasi-TE420 and quasi-TE240 modes via orthogonal slots, enabling dual polarization with high isolation and low sidelobe levels through amplitude-tapered feeding networks.
• An unequal power divider based on ridge gap waveguide achieves a large power division ratio, enabling compact two-dimensional amplitude tapering for sidelobe suppression.
• Measured results demonstrate a maximum gain of 25.6 dBi and radiation efficiency above 72% across both bands, confirming the feasibility of DMLS-based fabrication for high-performance antenna arrays.