A self-powered body area network node that uses thermal energy harvesting

The extensive research and increasing maturity in wireless and miniaturization technologies have empowered the development of small wireless sensors that are organized in a network. A keystone in this development is the body area network which places a network of wireless sensors on a human body to continuously monitoring physiological parameters. These millimeter size sensors need power to process data and to transmit these. Conventionally, batteries are used; however, the low amount of energy provided by these limits the data processing capability and the wireless communication range. In addition, recharging and replacing batteries are significantly impractical. In this paper an energy harvesting system is proposed to overcome the limitations of the batteries. The energy is harvested from the body-heat generated by a human body and converted to electrical power. A considerable part of this power is used to power a radio-transceiver to overcome the significant path loss and to provide wireless connectivity. From the simulations it have been found that the energy harvested from a small sensor is able to provide enough power to transmit a short message over a short distance.