الفهرس 
Title : An Integrated simultaneous thermal and rf energy harvesting system for wireless sensor networks
SummaryOnly 14 pages are availabe for public view
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Abstract
This work presents an integrated simultaneous thermal/RF energy harvesting
system that is suitable for low power wireless sensor networks. The system has
the ability to combine harvested energy from both DC and AC sources at the
same time and provide a regulated output voltage of 1.75V feeding a current load
from 0.15 mA to 0.77 mA. A triple mode maximum power point tracking (MPPT)
algorithm is implemented to achieve the best possible efficiency at different source
and load conditions. The three reconfigurable parameters in the system are the
number of stages of the DC path, the frequency driving the charge pump, and the
capacitors of the matching network in the RF-path. The energy harvester also
enables the storage of extra power by charging a supercapacitor in order to use
it during power shortage periods. The supercapacitor is charged using a voltage
doubler that has an output of 3.5V. The system is implemented in a 180 nm CMOS
technology and utilizes a total on-chip capacitance of 2.4 nF. Simulations show
that the overall end-to-end efficiency of the system reaches a maximum of 60.5%
at input thermal voltage of 350mV and RF input power of -8 dBmW.