Full 2-D Submillimeter-Wave Frequency Scanning Array

A 2-D frequency scanning array operating in the 220–320-GHz frequency band is presented. The array is composed of 64 open-ended rectangular waveguides arranged in an ${8\times 8}$ configuration. The feeding circuit comprises two waveguide-based phase shifting networks, which provides the required phase shift between adjacent radiating elements when the working frequency is modified. The array was manufactured over brass sheets through a mechanical procedure and experimentally characterized, providing beam steering along a $ {50 {^{\circ }}\times 45 {^{\circ }}}$ space region while the working frequency is swept between 220 and 320 GHz, with a maximum −10-dB secondary lobe level and a measured 17-dBi gain at 275 GHz.