  This paper presents an experimental evaluation on the accuracy of indoor
localisation. The research was carried out as part of a European Union project
targeting the creation of ICT solutions for older adult care. Current
expectation is that advances in technology will supplement the human workforce
required for older adult care, improve their quality of life and decrease
healthcare expenditure. The proposed approach is implemented in the form of a
configurable cyber-physical system that enables indoor localization and
monitoring of older adults living at home or in residential buildings. Hardware
consists of custom developed luminaires with sensing, communication and
processing capabilities. They replace the existing lighting infrastructure, do
not look out of place and are cost effective. The luminaires record the
strength of a Bluetooth signal emitted by a wearable device equipped by the
monitored user. The system's software server uses trilateration to calculate
the person's location based on known luminaire placement and recorded signal
strengths. However, multipath fading caused by the presence of walls, furniture
and other objects introduces localisation errors. Our previous experiments
showed that room-level accuracy can be achieved using software-based filtering
for a stationary subject. Our current objective is to assess system accuracy in
the context of a moving subject, and ascertain whether room-level localization
is feasible in real time.
