ASET Fall 2017 - 12

IN THIS CORNER FROM

NAIT

Wi-Fi-Based Trilateration
Location System
PROJECT TEAM
Graeme Pinkoski. I was born in Wainwright, moved to Edmonton upon graduating high school, and enrolled at NAIT
after spending seven years working in the golf industry. I
was general manager of my hometown golf course when
my wife and I had had our first child. We were looking for
a change of pace and decided I should go back to school.
NAIT's Computer Engineering Technology Program (CNT)
was appealing because I've always loved and been interested in all things technology. Upon graduation, I was hired
to develop software for Edmonton's Dynamic Manufacturing Solutions. I spend my leisure time with my wife of seven
years, Melanie, and our two children, three-year-old Lucas
our baby, Liliana.
Ryland Horton. I was born in Edmonton and grew up
in Sherwood Park. I chose to go to NAIT after working in
banking and deciding I'd like to do something more technically oriented. CNT looked like a great fit given that I love
the rush of building something that works and also found
myself drawn to computer programming. In my spare time,
I like to play games and work on personal programming
projects.

PROJECT SUMMARY
GPS is ubiquitous outdoors. Locations are tracked down to
the metre in the most inhospitable environments. Indoors,
however, no system exists to provide the level of location
to which people have grown accustomed. It is our contention that Wi-Fi signal strength information may hold the
key to locating a device, person, or piece of equipment in a
place where GPS cannot penetrate. Using RSS information
and a derived distance model, trilateration can pinpoint a
location between a set of overlapping Wi-Fi receivers. We
successfully built such a system and proved it works in a
real-world environment. Despite being limited by relatively
weak hardware, we achieved an accuracy level of approximately five metres, which could be improved with further
refinement. Additional research and development could
turn this technology into many different forms-from builtin location for valuable equipment to pinpointing your own
location within a mall.
The genesis of this project came from a problem presented by Graeme's wife, a nurse at a large local hospital.
The porters responsible for moving patients to different

12 | FALL 2017 | TECHNOLOGY ALBERTA

wards never know where to find an available stretcher. This
results in lengthy delays while they search different units,
trying to locate the necessary equipment. In trying to solve
this problem, Graeme thought of our upcoming Capstone
project. He and Ryland Horton came up with the idea of
using Wi-Fi to try to locate a transmitter that would be attached to a stretcher or other piece of medical equipment.
Our project summary includes an explanation of the
process we employed to develop the initial concept into a
fleshed-out product-the Wi-Fi Location System. Using a
system of four base units mapped around a known area
(2nd Floor, C Wing of NAIT's HP Centre), we were able to
track a transmitter device to an estimated position accurate to approximately 5 metres. This was accomplished
using a signal strength-to-distance conversion combined
with readings from each base unit, and an averaged trilateration algorithm. The location was saved in a database until
requested through the end-user interface, when it would
appear on an overlay of the mapped area.

Table of Contents for the Digital Edition of ASET Fall 2017