Design of 2×2 Interpolating-Fed 5×5-Element Phased Array Antenna-in-Package in 300-GHz Band

A 5×5 two-dimensional phased array was designed in 300-GHz band. Only 2×2 elements are fed from the feeding lines. Interpolating elements are located between the fed elements and surrounding the fed elements. The interpolating elements are excited through coupling circuits from adjacent elements. Although the fed elements are only 2×2 in a 5×5-arrangement, grating lobes are suppressed and the effective aperture is extended by surrounding elements. Thus, the directivity increases. The effect of the proposed technique on the phased array was confirmed by simulation in this work.