Development of an Integrated Hybrid Energy Harvesting System for Wireless Sensor Network Applications Using 180nm CMOS Process Technology

The presented hybrid energy combiner in the paper offers a promising solution for improving the energy efficiency of wireless sensor network (WSN) applications. By integrating Radio Frequency, piezoelectric, and thermal energy sources, the combiner maximizes energy harvesting capabilities. In addition, the results show that the combiner achieves high-efficiency levels ranging from 99.47% to 1.50% across different resistance values from 1-ohm to 10k ohms with ideal input voltage. Moreover, the highest peak end-to-end-efficiency of all the related works is 82.91% at power output of 160uW. Thus, this work has a 14.56% higher peak end-to-end than other related works. For the system to measure if there's an input, the conventional hysteresis comparator uses voltage level detection to make it pass through and then combine the energy sources. The combiner's three operating modes provide flexibility for adapting to various energy availability scenarios. Even with fewer energy sources, the combiner maintains notable efficiency.