Grating-Lobe Suppressing Feed Technique for 2D Phased Array with Interpolating Excitation Elements in 300-GHz band

A 3×3 two-dimensional phased array was designed in 300-GHz band. Only corner 2×2 elements are fed from the feeding lines. Interpolating elements are located between the corner fed elements. The interpolating elements are excited by coupling circuits from both sides in intermediate phase. Although the spacing between the fed elements is larger than a wavelength in free space, grating lobes are suppressed by radiation from the interpolating elements and gain increases. The effect of the proposed technique on the phased array was confirmed by simulation in this work.