Robustness of complementary wearable ungrounded antennas with respect to the human body

Several wearable antennas have been presented in the open scientific literature, showing a good robustness with respect to the body coupling effect, both on the input matching and on the antenna efficiency. In this work, we evaluate and compare the robustness with respect to the coupling with the human body of complementary structures. We focus on structures widely used as wearable antennas, namely the ungrounded meandered printed antennas (which are electric antennas), and the ungrounded meandered slot printed antennas (which are magnetic antennas). We will show that, although in non-wearable context these complementary structures are essentially equivalent, for wearable applications it is preferable to use magnetic antennas configurations, i.e. meandered slot printed antennas, because, by means of appropriate design choices, they can be far less sensitive to the proximity to the human body.