Compact Wide-Beam Scanning Dual-Polarized mmWave Array for Mobile Terminals

A compact wide-beam scanning dual-polarized (DP) array is designed for millimeter-wave (mmWave) applications in mobile terminals. The element is a coupled shorted patch antenna with quarter-wavelength resonance. Orthogonally slot coupled feeding is used to achieve the DP radiation. A close element distance of 0.4
λ₀
is chosen to construct the array. In order to decrease the coupling between close elements, the elements' positions are misaligned. Finally, the proposed DP mmWave array with a small size of 1.39
λ₀
× 0.42
λ₀
is achieved. A bandwidth of 24–28 GHz is realized for both polarizations. Within this band, the mutual couplings among adjacent elements are below −15 dB and the isolations between DP ports are above 20 dB. A wide 3 dB beam scanning range of ±60° for horizontal polarization radiation and ±50° for vertical polarization radiation is achieved. Within the beam scanning range, an acceptable less than −6.2 dB sidelobe level and a moderate below −15 dB cross-polarization level can be maintained. This compact wide-beam scanning DP mmWave array has the potential for future applications of mobile terminals.