The substrate and ground plane size effect on radiation pattern of 60-GHz LTCC patch antenna array

The influence of finite substrate and ground plane size on the radiation pattern performance of L-probe feed thick patch antenna-in-package array in low-temperature co-fired ceramic (LTCC) for 60-GHz wireless communications is investigated and compared when the antenna array is with and without the soft surface structure, which is used to reduce surface wave effect and improve the antenna performance. It is shown that the effect of the substrate and ground plane size effect on the radiation patterns of the array is significant and the shape of the main lobe will be distorted obviously when the antenna array is without the soft surface structure. On the other hand, the antenna radiation performance will not be affected too much by the substrate and ground plane size when the soft surface structure is added into the antenna array to reduce surface wave effect.