Local positioning in a bluetooth wireless network

Design team members: Cameron Woloshyn, Jeff Cote

Supervisor: Dr. Sagar Naik


As the world of wireless technology and its applications continue to grow, so does the periphery of technologies that are of value to this market. Location tracking is one of these technologies whose future growth and resultant need are undeniably.

Enhanced-911 (E911) is a federal mandate that is driving location tracking technology. In 1996 the FCC adopted a new mandate demanding wireless service providers to offer a location service equivalent to hard-line 911 location service.

E911 is not the only driving force behind location technology. Other promising applications are accident reporting, navigational services, automated billing, fraud detection, roadside assistance, and cargo tracking. These new services will provide revenues for wireless carriers estimated at 8 billion dollars by 2005. Position location technology will not only provide customers with new service options but also features that will differentiate services and markets. Lastly, location based systems will allow wireless carriers to adapt and charge their services depending on the location of mobile users, within a city, cell site.

Project description

The goal of this project is to enable position location at local level, appropriately called local positioning. The motivation behind local positioning is increasing the accuracy of existing position location systems. Existing generic infrastructure, specifically cellular networks, are not tailored for position location. It is thus possible to increase the accuracy of positioning systems by deploying an ad-hoc radio infrastructure whose purpose is solely to determine local positioning.

This increase in accuracy will allow location tracking systems to be used in situations where precise location (a few tens of meters) is desired. A newly feasible application now resides with real-time location tracking of firefighters and emergency medical services (EMS) in emergency situations.

Specific implementation technologies include utilising the Bluetooth ad-hoc wireless network standard to deploy the wireless network, and utilise a received signal strength indicator to determine distance from a mobile wireless source. Base stations with known positions across the network will triangulate their distances from the mobile source to determine the exact local position.

It is hoped that this system will be accurate to within 3-10 m.

Design methodology

A heuristic and iterative design methodology was employed to facilitate the design of this project. This methodology was created solely for the design of this project. Due to the minimal background knowledge the group members share in this field of research, an iterative approach needed be employed to allow redesign of components when new background information was uncovered. The flow of the methodology is presented below:

flow of the methodology in a flow diagram

Initially, a design solution is hyptothesised. This hypothesis is researched and an initial implementation is designed. This design is verified using qualitative and quantitative metrics, and renogotiated if the design is not suitable. This cycle is continued until the design is deemed suitable.