CyberMesh LoRaChat

A Decentralized Communication Device for Emergency Situations

🧠 Inspiration

Modern communication systems depend heavily on centralized infrastructure such as electricity grids, cellular networks, internet connections, and cloud servers. While these systems work well in everyday life, they often fail during disasters—floods, earthquakes, wildfires, or large-scale power outages.

When power and network infrastructure collapse, communication is usually the first thing to disappear—exactly when it is most critical.

This reality inspired the development of CyberMesh LoRaChat: a decentralized communication device designed to work without internet, cellular networks, or any central server. The project aims to provide a simple and reliable way to exchange text messages during emergencies using direct device-to-device communication.

Supplies

PICO2 (RP2350A) x2

RYLR998(LoRa) x2

ILI9341 x2

PIN HEADER 40 x2

Step 1: Concept Overview

CyberMesh LoRaChat is a peer-to-peer text messaging system built on LoRa (Long Range Radio) technology. Each device operates as an independent node capable of sending and receiving messages directly from other nodes.

There is no gateway, no cloud backend, and no single point of failure. Even if part of the network becomes unavailable, remaining devices can continue communicating.

This makes CyberMesh LoRaChat suitable for:

1. Emergency and disaster scenarios
2. Off-grid or remote areas
3. Backup communication systems
4. Educational and maker projects

Step 2: System Architecture

Each CyberMesh LoRaChat node consists of:

1. Raspberry Pi Pico 2 – main controller
2. ILI9341 TFT display – user interface
3. LVGL – graphical UI framework
4. MicroPython – firmware development
5. RYLR998 LoRa module – long-range wireless communication

Users can type, send, and receive short text messages through a simple on-device interface, similar to a basic chat terminal.

Step 3: LoRa RYLR998

📡 LoRa (RYLR998) Communication

LoRa technology is designed for long-range, low-power communication, making it ideal for emergency use where power and infrastructure are limited. Unlike Wi-Fi or cellular networks, LoRa operates independently of the internet and can transmit data over several kilometers with minimal energy consumption.

The RYLR998 LoRa module was chosen for this project because it offers:

1. Simple UART (AT command) control
2. Stable long-range performance
3. Low power consumption
4. Easy integration with microcontrollers

By handling the radio protocol internally, the RYLR998 allows the main controller to focus on user interface and message handling, keeping the system simple and reliable.

🔒 Why Decentralized Communication Matters

Traditional communication systems rely on centralized infrastructure such as base stations, servers, and network providers. When any of these components fail, communication stops entirely.

CyberMesh LoRaChat removes these dependencies by enabling:

1. Direct peer-to-peer messaging
2. Offline operation
3. No service fees or subscriptions
4. High resilience during infrastructure failure

With battery or solar power, the system can continue operating even when modern communication services are unavailable.

If you’re interested in building CyberMesh LoRaChat or experimenting with LoRa-based communication, the RYLR998 LoRa module used in this project is available from the following official global stores:

1. Amazon:
2. https://www.amazon.com/REYAX-RYLR998-Interface-Antenna-Transceiver/dp/B099RM1XMG
3. DigiKey:
4. https://www.digikey.com/en/products/detail/reyax/RYLR998/22078252
5. eBay:
6. https://www.ebay.com/itm/185968668254

Step 4: Power & Reliability

CyberMesh LoRaChat is optimized for low power usage:

1. LoRa minimizes transmission energy
2. MicroPython code avoids unnecessary background tasks
3. Can run on batteries for extended periods

This makes the device practical during prolonged outages.

Step 5: Circuit

Step 6: Code

Step 7: Future Development

Planned enhancements include:

1. Multi-node mesh message relaying
2. Group and broadcast messaging
3. Message encryption
4. GPS or sensor-based emergency status sharing

Step 8: Conclusion

CyberMesh LoRaChat demonstrates that reliable communication does not require complex or centralized infrastructure. By combining simple hardware, LoRa technology, and a decentralized design approach, the project provides a practical solution for maintaining communication during emergencies.

This project encourages makers and engineers to rethink communication—not only for convenience, but for resilience.