A Dual-band Dual-polarized Microstrip Antenna Array with Wideband and High Isolation for Ku-band

The design of a dual-band dual-polarized (DBDP) microstrip array with wideband, high isolation and low cross polarization working at 12.5 GHz and 14.25 GHz is described in this paper. Cross slots coupled multilayer antenna elements are employed to widen the bandwidth. The feed networks are placed on the opposite side to improve the isolation. Meanwhile, u-shaped delay lines are employed to obtain differential outputs to reduce the cross polarization. The simulation results show that the DBDP array exhibits an impedance bandwidth of 24.8% ranging from 11-14.1 GHz for Port H and 21% ranging from 12.7-15.7 GHz for Port V. The cross polarization level is better than -24 dB in E-plane (xoy) and -36 dB in H plane (yoz), and the isolation between ports is above 35 dB.