Challenges of wearable antenna design

Antenna design for wearable technologies is a challenging task due to the body being in the near-field of the antenna, the highly dynamic nature of the channel and the user acceptance issues. The antenna should be insensitive to the near field effects of the body in order to minimize detuning and to keep its efficiency high which translates to longer battery life time. Preferably, it could have a reconfigurable gain pattern to satisfy almost contradictory requirements of different links and to cope with the dynamic channel conditions. Finally the antenna should be either small or flexible for the users satisfaction while keeping the SAR levels low for safety. This paper discusses the aforementioned requirements in detail and proposes antennas tackling these challenges.