Can You Hear Me Now? A Survey of Communications Platforms During Emergencies

Slava opens with a practical question: when roads are blocked and normal infrastructure is down, how does an individual reach family miles away and coordinate with others? He frames radio as a frequency range combined with a modulation scheme, then uses that lens to compare the services available to private citizens in the United States.

The middle of the talk covers Citizens Band, Family Radio Service, General Mobile Radio Service and amateur radio. For each, he goes through licensing cost and effort, power limits, channel counts and typical range. He notes that CB can sometimes travel far through atmospheric propagation, while FRS and GMRS are mostly line of sight. He then turns to LoRa and Meshtastic, a low-cost mesh platform on ESP32-class hardware. The key security point is that encryption is permitted under the unlicensed Part 15 rules but prohibited under amateur Part 97, so an operator must choose between identifying with a call sign and using encrypted channels. He also demonstrates telemetry, GPIO control of remote hardware and MQTT bridging, and notes that crowded default channels saturate at large events.

He closes with practical advice. Antenna quality and height usually matter more than transmitter power, a station must be able to receive as well as send, and people should identify their likely risks and prepare before an emergency. The audience questions covered legal gray areas, node triangulation and power limits.