Project: Vortex Ring – Introduction and Theory

Introduction

Now that I have finally wrapped up EOGee/EOGlass I can focus on my next project. I decided to do something with magnetics because I wanted to build a little more applied intuition and understanding of magnetic sensors and actuators. My original plan was to investigate building my own electro-permanent magnets, because I can think of some interesting applications for a switchable magnet. However in the process of my research I came up with a new idea for a wearable communication technology.

Human Body Communication (HBC) is a catch-all term for communication methods that use the human body as a communication channel. This means that the signals are contained within the human body and do not travel through a wire or through the air. This is potentially useful in wearable devices that may need to communicate with each other, for example a smart-watch can communicate with a heart rate monitor on the user’s chest, or an accelerometer on their leg, or even a medical device like pacemaker or cochlea implant. In such a network, all devices can communicate with a central hub (e.g. smart-watch) that then communicates to the user’s phone or other device to deliver the data to the user. Advantages of this approach potentially include reduced power consumption (due to the body’s higher channel gain compared to air), reduced network congestion (as each human will constitute a separate network rather than all sharing the air), as well as increased security and/or privacy (since the signals are constrained to the user’s body).

There are two broad classes of HBC – galvanic (where current is used to transmit information) and capacitive coupling (where voltage is used to transmit information). These are described in the paper A Review on Human Body Communication: Signal Propagation Model, Communication Performance, and Experimental Issues by Zhao et al.

Galvanic and Capacitive Coupling Human Body Communication
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