Faculty Publications

A Joint Power Harvesting And Communication Technology For Smartphone Centric Ubiquitous Sensing Applications

Document Type

Conference

Keywords

3.5mm Audio Interface, Frequency Shift Keying, Power Harvester, Smartphone, Ubiquitous Sensing

Journal/Book/Conference Title

IEEE International Conference on Electro Information Technology

Volume

2015-June

First Page

268

Last Page

273

Abstract

With the popularization of smartphones, various smartphone centric ubiquitous sensing applications have emerged, which use a smartphone in conjunction with external sensors for data acquisition, processing, display, communication, and storage. Because smartphones made by different manufacturers do not have a common data interface, many ubiquitous sensing applications use the 3.5mm audio interface for communications so that they can work with different types of smartphones. The 3.5mm audio interface cannot provide DC power to external sensors. Thus, power needs to be harvested from an earphone channel. The existing technology uses one earphone channel to transfer data from a smartphone to external sensors and harvest power from the other earphone channel. Consequently, for many smartphones the technology cannot harvest enough power to support external sensors. In this paper, based on frequency shift keying (FSK) modulation scheme, we have proposed a joint power harvesting and communication technology that can simultaneously harvest power and transfer data with the same earphone channels. Circuit measurements show that by coherently harvesting power from both earphone channels, the proposed technology can extract more than two times of power as from one earphone channel. Meanwhile, demodulation tests show that our newly developed timer-based FSK demodulator can reliably recover the data transferred from a smartphone to external sensors without any error.

Department

Department of Technology

Original Publication Date

6-10-2015

DOI of published version

10.1109/EIT.2015.7293351

Share

COinS