Using thermoelectric energy harvesting to power a self-sustaining temperature sensor in body area networks

In this paper a thermoelectric energy harvester with an active area of 0.5×0.2mm² fabricated in a 130nm process is presented. By using automatic frequency adaptation the circuit is able to operate even in the sub-threshold region at about 230mV. The harvester powers a self-sustaining active wireless sensor node for temperature measurement in body area networks. Therefore it extracts power from a difference in temperature of about 1K using 2 thermo electric generators. This sensor measures the temperature and transmits data at a rate of 250kBit/s in the 868MHz ISM-band using ASK-modulation to the receiver side. The sensor is operated in a duty-cycle mode.