EchoMesh: A Decentralized Off-Grid LoRa Mesh Communication System for Emergency and Remote Connectivity

Modern communication systems rely heavily on centralized infrastructure like cellular towers, internet backbones, and cloud services. During natural disasters, military conflicts, remote expeditions, and large public events, these infrastructures often fail or become congested, causing communication breakdowns. This research introduces EchoMesh, a decentralized LoRa-based mesh communication system designed for off-grid communication using low-power embedded devices. EchoMesh enables text messaging, GPS sharing, emergency SOS signaling, and low-bitrate voice transmission without relying on cellular networks or internet connectivity. The system uses ESP32 microcontrollers, SX1276 LoRa transceivers, Bluetooth Low Energy (BLE), GPS modules, and open-source firmware architecture. It combines mesh routing, AES-128 encryption, and hybrid mobile integration through a Flutter-based smartphone app. This research evaluates how well long-range communication can work with low power consumption while keeping scalability and reliability in disaster-response and rural communication scenarios.