MPPM Based Bi-directional Long Range Visible Light Communication for Indoor Particulate Matter Monitoring

In this study, we have focused on monitoring indoor particulate matter by using multiple pulse position modulation (MPPM) to transfer fine particulate matter (PM) data in long distance. According to the world health organization, PM has a dangerous effect on the human body and causes different deadly diseases. Previous studies have showed that exposure to PM-related pollution causes cardiovascular and other respiratory diseases. Thus, it is crucial to measure PM concentration in places like hospitals and nursing homes. Visible light communication (VLC) is used for short-range optical communication. VLC has features like electromagnetic interference-free, virtually unlimited bandwidth, no known health effect to the human body, and secure communication. MPPM is a modulation technique which is power efficient compared to other modulation schemes. We have applied the MPPM by (4, 2) formation where 4 is the slot length and 2 pulses in each slot, to send bits in long-distance transmission using VLC. Two nodes used to complete the bidirectional communication, one node requests the sensor data, and another sends the response. We have achieved a 15 m distance between two nodes with a reliable error rate.