Experimental Characterization of Wearable Antennas and Circuits for RF Energy Harvesting in WBANs

Field trials have been performed in Covilhã to identify the spectrum opportunities for radio frequency (RF) energy harvesting through power density measurements from 350 MHz to 3 GHz. Based on the identification of the most promising opportunities, a dual-band printed antenna was conceived, operating at GSM bands (900/1800), with gains of 1.8 and 2.06 dBi, and efficiency varying from 77.6 to 82%, for the highest and lowest operating frequency bands, respectively. In this paper, guidelines for the design of RF energy harvesting circuits and choice of textile materials for a wearable antenna are briefly discussed. Besides, we address the development and experimental characterization of three different prototypes of a five-stage Dickson voltage multiplier (with and without impedance matching circuit) responsible for RF energy harvesting. All the three prototypes (1, 2 and 3) can power supply the sensor node for RF received powers of 2 dBm, -3 dBm and -4 dBm, and conversion efficiencies of 6, 18 and 20%, respectively.

Keywords

Radio Frequency Energy Harvesting Wireless Body Area Networks Wearable Antenna Voltage Efficiency

URI

http://hdl.handle.net/10400.6/15169

Citation

Henrique M. Saraiva, Luis Borges, Norberto Barroca, Jorge Tavares, Paulo T. Gouveia, Fernando J Velez, Caroline Loss, Rita Salvado, Pedro Pinho, Ricardo Gonçalves, Nuno Borges de Carvalho, Raúl Chávez-Santiago and Ilangko Balasingham, “Experimental Characterization of Wearable Antennas and Circuits for RF Energy Harvesting in WBANs,” in Proc. of VTC2014-Spring - IEEE 79th Vehicular Technology Conference: VTC2014-Spring, Seoul, South Korea, May 2014.