Multi-Band Patch Antenna Array for Out-of-Band Aided Millimeter Wave Communication

Future wireless communication systems will integrate both sub-6 GHz and millimeter wave (mmWave) frequency bands within multi-antenna architectures to meet the increasing demand for high data rates. In such multi-band systems, reliable information obtained from the sub-6 GHz band can be exploited to support communication at mmWave frequencies. To ensure that both systems experience similar multi-path propagation effects, the sub-6GHz and mmWave antenna arrays have to be colocated and precisely aligned. However, such a configuration may adversely alter the radiation characteristics of the arrays, potentially degrading their performance. In this paper, we investigate the impact of positioning a mmWave antenna structure in front of a sub-6 GHz antenna structure. Through both simulations and measurements, we evaluate how the presence of the mmWave structure affects the radiation pattern of the sub-6 GHz one. The results demonstrate that the influence of the mmWave structure on the sub-6 GHz performance is minor, indicating that co-located configurations are feasible with negligible degradation.