Aperture-Shared Base-Station Antenna Array Design Based on EM Transparency

A dual-polarized antenna designed for electromagnetic (EM) transparency is introduced as a low-band (LB) antenna within an aperture-shared antenna system ensuring the radiation pattern of high-band (HB) antenna remains intact. The EM transparency is accomplished by incorporating two types of cross-slots into the radiator of LB antenna. These two types of cross-slots are overlapped together to form a composite resonant slot. Since the bandpass response in HB, the composite resonant slots contribute to counter the radiation of HB induced currents on the LB antenna, resulting in minimal impact on the radiation patterns of the HB antenna. For demonstration, a prototype dual-band antenna array has been constructed, covering the LB of 1.7-2.56GHz (VSWR<1.5) and the HB of 3.3-3.8GHz (VSWR<1.5), is fabricated. The simulation results confirm effectiveness of the array in preserving the radiation performance of the HB antenna.