[LFOD1]

Many thanks for your question! It prompted me to rethink a problem in Home Telehealth and Elder-Care having to do with tracking Dementia patients. Anyway, a PubMed paper published 2018-1-24 titled: Passive Infrared (PIR)-Based Indoor Position Tracking for Smart Homes Using Accessibility Maps and A-Star Algorithm (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5855945/) may help you.

The paper is about using passive infrared sensors (active badge etc.) to accomplish indoor position tracking. This may be overkill for your need but I figured I'd put it out there for you anyway. I hope to have some follow up information in a couple of days and will revisit this question.