Design and fabrication of a double-layer slotted waveguide array with a partially-corporate feed for 38GHz fixed wireless access systems

A 20x20-element double-layer array is designed at 38.7GHz. A broadband structure with 2x2 sub-arrays is realized by introducing the partially-corporate feed circuit. As the design results, a maximum directivity of 35.0dB and a high antenna efficiency of 94.0% are realized at 38.7GHz. For demonstration, the designed antenna is fabricated by diffusion bonding of thin copper plates. As the measurement results, a high aperture efficiency of 87.5% with the directivity of 34.7dB is realized in the first fabrication. The maximum antenna gain of 33.9dBi is measured at 38.5GHz, where the corresponding antenna efficiency is 73.2%. The screwing penetrating the antenna is adopted to install two separated antennas on the wireless terminal. By introducing a shielding metal wall of 12mm in width and 10mm in height, a high isolation of 75dB is predicted with the radome taken into account.