Indoor Positioning Using Infrastructure
Indoor Positioning using
Infrastructure
Nicolas Constantinou
January 8, 2013
1
Abstract
Outdoor positioning has proved to be very functional during the years, recently indoor positioning systems which I will be referred to as IPSs have been designed to provide location information of persons and devices. Numerous IPSs are being developed using different infrastructure so the best solution for every situation can be found. This paper gives information and talks about the different IPSs, some comparing occurs, what can be improved and aims to review current development and future scope of this technology.
2
Introduction
Traditionally location aware applications have been used to outdoor environments, using mostly GPS. However very large and complex buildings exist these days, people have difficulties finding what they are looking for in the stated buildings (museums, hospitals, shopping centers, etc). Knowing where you are and navigating faster in such environments can increase the productivity and the quality of service provided by those services. IPSs haven’t had as much research as Outdoor Positioning Systems. Reasons of these are two technical problems. First GPS signals cannot reach indoor environments and second the complexity of indoor environments makes triangulation based approaches (which are used for GPS) less effective. Some early systems using infrared, laser and ultrasonic range finders got good system performance in field tests but such an approach isn’t appropriate because of its size, complexity and cost. Some researchers have been working on using WiFi even though it was not designed for this purpose. Most of these systems use a fingerprinting approach due to the infeasibility of indoor triangulation. Fingerprinting
1
is based on the Received Signal Strength (RSS) transmitted by nearby WiFi access points. Although RSS may be of low cost and low complexity due to the large signal variance, insufficient data and changing
Infrastructure
Nicolas Constantinou
January 8, 2013
1
Abstract
Outdoor positioning has proved to be very functional during the years, recently indoor positioning systems which I will be referred to as IPSs have been designed to provide location information of persons and devices. Numerous IPSs are being developed using different infrastructure so the best solution for every situation can be found. This paper gives information and talks about the different IPSs, some comparing occurs, what can be improved and aims to review current development and future scope of this technology.
2
Introduction
Traditionally location aware applications have been used to outdoor environments, using mostly GPS. However very large and complex buildings exist these days, people have difficulties finding what they are looking for in the stated buildings (museums, hospitals, shopping centers, etc). Knowing where you are and navigating faster in such environments can increase the productivity and the quality of service provided by those services. IPSs haven’t had as much research as Outdoor Positioning Systems. Reasons of these are two technical problems. First GPS signals cannot reach indoor environments and second the complexity of indoor environments makes triangulation based approaches (which are used for GPS) less effective. Some early systems using infrared, laser and ultrasonic range finders got good system performance in field tests but such an approach isn’t appropriate because of its size, complexity and cost. Some researchers have been working on using WiFi even though it was not designed for this purpose. Most of these systems use a fingerprinting approach due to the infeasibility of indoor triangulation. Fingerprinting
1
is based on the Received Signal Strength (RSS) transmitted by nearby WiFi access points. Although RSS may be of low cost and low complexity due to the large signal variance, insufficient data and changing