An energy efficient MAC protocol for mobile in-vivo body sensor networks

Body sensor networks (BSNs) is a challenging research area that have attracted many researchers in recent times. Examples of BSN applications include those that are used to detect vital signs of the human body. As these body sensor devices are typically powered by batteries that are difficult to replace, energy efficient MAC protocols play an important role in BSNs. In this paper, we propose a novel TDMA-based energy efficient MAC protocol for in-vivo communications between mobile nodes in BSNs using an uplink/downlink asymmetric network architecture. A TDMA scheduling scheme and changeable frame formats are also proposed. An adaptive power control scheme is designed especially for the mobile sensor scenarios presented. Simulation results based on the random mobility pattern show that the power consumption of the proposed MAC protocol is much lesser than that of the star topology TDMA. Furthermore, it is also shown that the latency performance can be improved by reducing the data slot duration.