Millington Effect and Propagation Enhancement in 60-GHz Body Area Networks

Millington effect for on-body propagation enhancement is presented in the 60-GHz band. Millington's equations are developed to describe propagation above a flat inhomogeneous surface. This study focuses on mixed paths (human skin-metallic) for on-body scenarios. It is shown that adding metallic paths on the human skin can improve the power link budget between two nodes placed on the body. Two different schemes are studied experimentally to assess the analytical model using a flat phantom with electric properties of human skin and different lengths of metallic inserts. The first scheme considers a metallic plate between the transmitting and receiving antennas, while the second scheme proposes locating the metallic plates under the antennas. It is shown that the second scheme yields a better link budget than the first one for the same length of metal. Moreover, a numerical study is performed to assess the impact of the following different parameters: the location of the metal plate, size of the plate, and the height of the antennas. Excellent agreement between numerical and experimental results has been shown. In the best cases, the presented techniques allow to improve the path loss of 10-20 dB.