A Beam-Steerable Conformal Waveguide Slot Array Based on a Mechanical Tunable Phase Shifter

This letter proposes a novel conformal waveguide slot array with characteristics of wideband and high gain for beam-scanning applications. The antenna comprises two key modules: an arc ridge waveguide mechanical phase shifter and a 4 × 6 conformal ridge waveguide slot array. The mechanical tunable phase shifter dynamically rotates the SMA feeding position along concentric arc-shaped waveguides to vary the path difference of propagating waves, thereby achieving equivalent phase shift modulation and enabling the antenna with beam-scanning capability in its elevation plane. Experimental results demonstrate that the measured S ₁₁ of the proposed antenna is below −10 dB in the 4.5 GHz to 5.5 GHz range. Moreover, the array demonstrates a beam-scanning angle of up to 24° in the H-plane and 13° in the E-plane, with a peak gain of 22 dBi. By combining the low-cost, tunable phase control of mechanical actuation with the geometric versatility of additive manufacturing, the proposed design offers a compact, high-performance, and highly integrated beam-steering solution, which is promising for advanced mobile communication and sensing platforms.