A Review on State of Art Techniques of Antennas for Body Area Networks

In this paper, we explore some of the notable research works that will open a new dimension in the field of antenna research applicable to body area networks. Different types of antennas for body area networks include implantable antenna, ingestible pill antenna, and wearable antennas. The antennas for body area networks gained the attention of the researchers after the demands of the compact as well as efficient wearable devices increased. The design of antennas for body area network applications is very interesting and challenging, as a researcher has to ensure that the antenna should have a small footprint, and be flexible. Simultaneously, the radiation must be in a particular direction with a workable gain, and low Specific Absorption Rate (SAR) to avoid damage. These antennas require performing well in proximity to the living bodies that tend to degrade the performance. The antennas that are in demand include implantable antennas, ingestible antennas, on-body antennas, and antennas for off-body communications. In this paper, the earlier works have been analyzed well and verified with a compact CPW-fed circular patch antenna design, backed by a metal conductor. This antenna exhibits the perfect matching at two frequency bands. These are S11 (below -10 dB) bandwidth of 3.4 GHz ranging from 2.45 – 5.89 GHz and an S11 bandwidth of 0.99 GHz ranging from 9.10 – 10.09 GHz. While in contact with the human body, the antenna exhibits a bandwidth of 2.54 GHz between 3.02-5.56 GHz and a bandwidth of 3.01 GHz between 9.8-12.81 GHz. The SAR values are 0.82 W/kg and 0.56 W/kg. The antenna is a suitable candidate for off-body communication in wearable applications.