Fundamental study on a perturbed patch antenna on small ground plane aimed at multi polarization and matching stability on WBAN applications

Characteristics of antennas and propagation channels in on-body communications have been ascertained. Earlier studies indicated that not only maximization of path loss between body-mounted devises by use of monopole-like antennas but also countermeasures against fading by use of multi polarization antennas may be an important issue. Multi polarization can be obtained by perturbing the patch antennas. That is well known as circularly polarized patch antennas. In this paper, a perturbed patch antenna on a small ground plane in vicinity of the human body is characterized for some purposes such as challenge for co-existence of antenna and the human body rather than shutting out the body effects. Specifically, variation of input impedance, axial ratio, radiation efficiency, and radiation pattern of the antenna are evaluated by use of numerical calculation.