Double-layer slotted waveguide array antennas with corporate-feed by diffusion bonding of laminated thin metal plates

We demonstrate two types of double-layer slotted waveguide array antennas by diffusion bonding of laminated thin metal plates. Etching metal plates gives high precision at low cost and diffusion bonding gives perfect electrical connection in the slotted waveguide array, in millimeter-wave bands. Corporate feed is adopted to increase the bandwidth of a series-fed array antenna. A 38GHz antenna with partially corporate feed gives 73.2% peak efficiency with 33.9dBi at 38.5GHz in measurement at this moment. A 60GHz antenna with full corporate feed gives more than 32dBi and 80% efficiency over about a 5GHz bandwidth in measurement.