Design and Analysis of a Large-Scale BLE Mesh Network

In the Bluetooth mesh network specifications, nodes supporting mesh network specifications can only transmit on advertising channels, and forwarding is based on flooding, causing many redundant packets to be transmitted in the network, wasting the already very limited Bluetooth network bandwidth. Due to these reasons, when the number and density of nodes increase or when the network transmission volume is large, the probability of packet collisions in the network will be significantly increased, easily causing channel congestion, making it impossible to increase the size and density of Bluetooth mesh networks. Therefore, we propose a hierarchical clustering architecture, where cluster heads in the upper layer form a unicast multi-hop tree backbone network for Bluetooth Low Energy, and each cluster in the lower layer uses an improved mesh broadcast. Not only does the broadcast range shrink to within a single cluster, but it also allows inter-cluster communication using BLE data channels. This enables effective transmission between network nodes, maintaining the entire network's stability and throughput while increasing the topology's size and density.