Single-Layer Planar Waveguide Array Antenna With High Antenna Efficiency

This letter proposes a 60 GHz planar waveguide array antenna with high antenna efficiency, low cost, and low processing difficulty. The array integrates the radiating elements and the hollow
E
-plane waveguide feed network in a single-layer structure in a simple way. To demonstrate the idea, a 16×16 prototype was designed, fabricated, and measured. The measured 10 dB impedance bandwidth (|S
₁₁
| ≤ −10 dB) is 16.4% with the antenna efficiency being 89.1% at 61.5 GHz. To the best of our knowledge, it has the highest antenna efficiency and the lowest processing difficulty among similar waveguide arrays.