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Top1. Introduction
Body area network is showing tremendous growth in the domains of health monitoring and tracking, soldiers monitoring, sports and entertainment industry. The electronic devices and gadgets use wireless communication to transfer data and antenna is most important part of these devices. The Body area network uses licensed wireless medical telemetry services (WMTS), licensed Medical Implant Communication services (MICS), unlicensed Industrial, Scientific, and medical (ISM) band, and ultra-wide band(UWB), etc. (Ullah et al.., 2009). There are some restraints related to the design of these antennas: small size, robustness, low power consumption and easiness (Gareth A. et al.,2009; Rahmat-Samii et al., 2005).
Integration of antennas over the wearable textile is investigated by many investigators including (Rahmat-Samii et al., 2005; Ouyang et al., 2005; Tanaka et al., 2005), it presents linearly polarized wearable antennas. Electromagnetic band gap structures based fabric antennas are investigated in (Zhu et al., 2007). As a part of Body Area Network MICS band antennas are analyzed by (Guo et al., 2007), working in 402-405MHz.The state-of-the-art in the research field of implanted devices has shown that MICS (402–405 MHz) band can be utilized in communication with medical implants (IEEE1999). The European Telecommunications Standards Institute (ETSI) and FCC have standardized the MICS: the maximum emission bandwidth to be occupied is 300 kHz, the equivalent radiated power (ERP), i.e. the maximum field-strength in any direction should be equal to, or lower than, what a resonant dipole would give in its maximum direction at the same distance, with the dipole being fed with a signal of 25 micro watt (FCC 1996). International Telecommunication Union (ITU) defined ISM bands (2.4–2.4835 GHz) and the use of radio frequency (RF) energy is for industrial, scientific and medical purposes other than communications.
Figure 1. Locations of Implanted antennas on human body (a) Arm (b) Head (Kiourti et al. & Yazdandoost, 2012)
The performance of planar inverted F antenna (PIFA) for body worn applications and proximity of human body to antenna is discussed by (Terence SP. Et al, 2005). Similarly, different ISM band antennas are reported in (Kamarudin MR., 2005) e.g.; monopole antennas, patch antenna and its arrays in proximity of human body. Large dimensions of the antennas are major limitations for implanted of body worn antennas.