IMep: Device-Free Multiplayer Step Counting With WiFi Signals

Currently, most of the mature WiFi-based step applications can only count the steps of a single individual, and their methods cannot capture amplitude information about each person's overall actions in multiuser scenes. It is still a challenging task to build a multiplayer step counting system in a device-free manner. In this paper, we present IMep, a novel device-free system based on WiFi that can obtain the amplitude information of each person's overall step actions and count the steps of multiple people simultaneously. Our main strategy is to establish a Multiplayer Stepping Amplitude Relation Model (MSARM) and design a Multiplayer Amplitude Decomposition Algorithm (MADA) that uses Block Term Decomposition (BTD). Moreover, we put forward a new Moving Energy Method (MEM) that captures each person's step number more clearly and accurately. The experimental results show that, IMep can function successfully in an environment of up to 7 people. The accuracies in three different room settings are 95.57%, 94.66%, and 89.94%, respectively, suggesting that IMep is effective in multi-person scenarios.