Powering the next Billion devices with wi-fi

Abstract

-We present the first power over Wi-Fi system that delivers power and works with existing Wi-Fi chipsets. Specifically, we show that a ubiquitous piece of wireless communication infrastructure, the Wi-Fi router, can provide far field wireless power without compromising the network's communication performance. Building on our design we prototype, for the first time, battery-free temperature and camera sensors that are powered using Wi-Fi chipsets with ranges of 20 and 17 feet respectively. We also demonstrate the ability to wirelessly recharge nickel-metal hydride and lithium-ion coin-cell batteries at distances of up to 28 feet. Finally, we deploy our system in six homes in a metropolitan area and show that our design can successfully deliver power via Wi-Fi in real-world network conditions.

Radio Frequency Energy Harvesting Sources

“…Olgun [22], also in 2012 successfully powered a temperaturehumidity sensor with a 3x3 miniaturised antenna array from a Wi-Fi router. In 2013, Hong [35] [20,21] designed a novel Power Over Wi-Fi (POWIFI) harvester that successfully harvested energy from a 2.4 GHz Wi-Fi router. The harvesters successfully powered a camera, a temperature sensor, Li-Ion and NiMH battery chargers.…”

“…Energy can be harvested from external sources such as solar radiation [1][2][3], thermal energy [3-5], mechanical vibrations [5-10] and radio frequency (RF) sources [5][6][7][8][9]. Among these ambient energy sources, there has been a dramatic growth of RF energy harvesting mainly because of the abundant availability of electromagnetic signals such as television/ digital television (TV/DTV) [11][12][13], FM/AM radio [14,15], mobile base stations and mobile phones [16][17][18][19], and Wi-Fi signals [20][21][22][23][24]. The recent interest in RF harvesting has also been driven by the great progress in both wireless communication systems and broadcasting technologies that have availed a lot of freely propagating ambient RF energy [25][26][27][28][29].…”

Optimization of Power Transfer Efficiency and Energy Efficiency for Wireless-Powered Systems With Massive MIMO

“…Remark 3: We note that the LS channel estimate is a scalar multiple of that obtained with the MMSE approach. Specifically,ĝ LS i = 1 + σ 2 βiτ pTr,i ĝ MMSE i for i ∈ I K , which follows by simplifying (6) and (13). In other words, the phase of the estimated channel remains the same with LS and MMSE.…”

“…An RF or wireless energy harvesting device extracts energy from the incident RF signals. Such wirelessly powered systems are becoming more feasible due to the reduction in the power consumption requirements of devices and the advancement in energy harvesting technologies [9], [11]- [13]. T This work was presented in part at IEEE 2017 VTC-Spring [1].…”

Information and Energy Transmission With Experimentally Sampled Harvesting Functions

“…Moving beyond the point-to-point case, we also consider a multiterminal setting. As well as other multiterminal settings [22], [23], a setting of medium access as in the Wi-Fi downlink protocol has been of recent interest in energy transmission using downlink Wi-Fi, but largely disconnected from optimal physical-layer designs [24]. In particular we consider multicast from a central access point, where energy and the same message are desired by several receivers, as in the beacon signal and protocol information that take up much of Wi-Fi traffic.…”