Abstract
In this paper we present a wearable positioning system that requires less
than 10~mW to operate.
The system consists of an infrastructure of ultrasonic
transmitting devices, and a receiver device on the wearable. The receiver
comprises an ultrasonic pick-up, an op-amp, and a PIC. The PIC implements a
particle filter for estimating X and Y positions. The transmitter layout
has been chosen to simplify the maths in the PIC so that the particle
filter reduces to just two multiplication operations per particle. We have
modified the traditional particle filter in order
to operate on a micro-controller with
severely limited memory capabilities. The advantage of using a particle filter over
other filtering techniques is that a particle filter is robust in
environments with limited precision; all our data is stored as 8-bit. The
number of particles is only limited by the amount of memory on the PIC; we
only use 5% of the PIC's computational power.
| Translated title of the contribution | A 10mW Wearable Positioning System |
|---|---|
| Original language | English |
| Publisher | Department of Computer Science, University of Bristol |
| Publication status | Published - 2006 |
Bibliographical note
Other page information: -Other identifier: 2000561