Summary and Future Challenges
Body area communications is a short range wireless communication technique in the vicinity of, or inside, a human body. The different operating environments mean that the body area communications is classified into on-body, in-body or in-body/on-body to off-body communication scenarios. It can provide a wide range of applications such as medical and healthcare services, assistance to people with disabilities, and consumer electronic connectivity and user identification.
As an introduction to body area communications, we have started with basic electromagnetic characterization and modeling methodology for the human body in various possible frequency bands. Based on the basic knowledge, we have focused on three major areas: channel modeling, modulation/demodulation performance, and EMC consideration in body area communications.
Body area communications is being considered to operate in UWB, MICS, ISM and HBC bands. Since electrical properties of human tissue are frequency-dependent, a Debye-type approximation expression is a useful means for modeling them. The basis for modeling the frequency dependence uses the dispersion phenomena in the dielectric spectrum of tissue. The dielectric spectrum is characterized by several dispersion regions. Each of them can be characterized by a single relaxation time constant in the Debye expression. The dielectric properties of the human body are then expressed as a summation of terms corresponding to the ...