Abstract

There are many positioning technologies that operate using high frequency radio signals, such as GPS , WiFi and UWB . Due to the radio-complex environment in which they operate and the short wavelength, radio propagation is typically subject to multipath, scattering and absorption. This in turns leads to ever more sophisticated algorithms to mitigate the effects of the disturbance. In this talk, I will discuss a fresh approach to positioning and communication using low frequency ( < 100 kHz) magnetic fields. By measuring the vector field, our technique has the unique ability of being able to position in 3-D using a single transmitter and single receiver, unlike traditional trilateration approaches which typically require at least four spatially separate transmitters. Operating in the near-field, there is no possibility for multipath to occur, resulting in accurate and low noise positioning. In addition, low frequency fields have the ability to penetrate soil, rock and water with minimal attenuation, opening up the possibility of localizing in challenging environments such as underground or indoors. I will discuss some of the techniques and algorithms we are currently developing and present some recent results, as well as highlight challenges in using low frequency fields.