Radio frequency (RF) energy harvesting is an emerging
technology that will enable to drive the next generation of wireless sensor networks (WSNs) without the need of using batteries. In this paper, we present RF energy harvesting circuits specifically developed for GSM bands (900/1800) and a wearable dual-band
antenna suitable for possible implementation within clothes for
body worn applications. Besides, we address the development and experimental characterization of three different prototypes of a five-stage Dickson voltage multiplier (with match impedance
circuit) responsible for harvesting the RF energy. Different
printed circuit board (PCB) fabrication techniques to produce the
prototypes result in different values of conversion efficiency.
Therefore, we conclude that if the PCB fabrication is achieved by
means of a rigorous control in the photo-positive method and
chemical bath procedure applied to the PCB it allows for attaining better values for the conversion efficiency. All three prototypes (1, 2 and 3) can power supply the IRIS sensor node for RF received powers of -4 dBm, -6 dBm and -5 dBm, and conversion efficiencies of 20, 32 and 26%, respectively.