True-Time-Delay Mechanical Phase Shifter in Gap Waveguide Technology for Slotted Waveguide Arrays in Ka-Band

This article proposes a novel all-metal mechanical phase shifter in gap waveguide technology. The phase shifter is aimed at providing beam-scanning capabilities to conventional slot array antennas along the elevation plane. To validate experimentally the beam-steering functionality, a 4x8 slot-array antenna has been designed and fabricated, along with the phase-shifting mechanism. The whole antenna consists of two pieces: a lower rotatable block, which changes the length of concentric groove gap waveguides, and an upper fixed block, where the slot-array antenna is placed. Experimental results validate the proposed concept, having obtained steering angles of up to 25 degrees, with gain levels around 20 dBi with an antenna efficiency close to 90%. A reflection coefficient below -10 dB is achieved for a wide range of rotation angles from 29.5 to 30.5 GHz. The proposed phase shifter is completely scalable to any array size and its true-time-delay nature enables wide steering ranges for closely-spaced slot arrays with wideband radiation performance.

Automated summary

This article introduces a novel all-metal mechanical phase shifter in gap waveguide technology to provide beam-scanning capabilities to conventional slot array antennas. Experimental results validate the effectiveness of the proposed concept, achieving significant steering angles and high gain levels.