LoRa Wireless Sensor Network
Implemented a long-range, low-power sensor network for remote environmental monitoring using LoRa modulation and ESP32 microcontrollers.
LoRa Wireless Sensor Network
Remote telemetry often requires a balance between range and power consumption. This project implements a point-to-multipoint network using LoRa (Long Range) technology to aggregate data from distributed environmental sensors.
Specifications
- Frequency: 868 MHz (ISM band).
- Hardware: ESP32 + SX1276 LoRa modules.
- Topology: Star network with one Gateway and multiple Sensor Nodes.
Protocol Design
To optimize for battery life, I implemented a simple Time Division Multiple Access (TDMA)-like polling scheme:
- Deep Sleep: Sensor nodes sleep for 10 minutes.
- Wake & Measure: Wake up, read temperature/humidity/pressure.
- Transmit: Send encrypted packet to Gateway.
- Ack: Wait 200ms for acknowledgment.
// Packet Structure
struct LoRaPacket {
uint8_t device_id;
uint32_t timestamp;
float temp;
float humidity;
uint16_t battery_mv;
};Field Test
The system was tested in an urban environment, achieving stable link quality at distances over 2 km line-of-sight using simple wire antennas. The sensor nodes operated for months on a single 18650 Li-Ion cell.