What Is LoRa? (For Beginners)
LoRa stands for “"Long Range.”" It is a radio modulation technique from Semtech that enables very long range wireless communication at very low power, at the cost of low data rates —- the physical layer beneath Meshtastic and MeshCore.
How it works
LoRa uses chirp spread spectrum —- the signal is spread across a wide frequency band using a continuously sweeping chirp tone. This spreading gives LoRa extraordinary resilience to noise. A receiver can decode a packet even when the signal is far below the background noise floor —- a capability no conventional modulation scheme matches.
Key characteristics
- Range:
1–1 - 15 km typical;30–30 - 50+ km achievable with elevated antennas - Data rate: 0.
2–2 - 22 kbps depending on preset—- slower than a 1990s modem, but sufficient for text and GPS - Power: Nodes run days to weeks on a small battery;
8–8 - 50 mA active depending on hardware - No subscription: Operates in the unlicensed
902–902 - 928 MHz ISM band in North America. No SIM, no carrier fees. - License-free: Standard operation under FCC Part 15.247 requires no amateur radio license
What LoRa is NOT
- Not WiFi: Far slower, far longer range. No web browsing or streaming.
- Not cellular: No towers, no coverage maps, no subscription. Works anywhere two nodes are within radio range of each other.
- Not LoRaWAN: LoRaWAN is a specific hub-and-spoke IoT architecture. Meshtastic and MeshCore are peer-to-peer mesh networks. Same radio hardware, completely different protocols. See the LoRa Mesh vs. LoRaWAN page for the full comparison.
- Not Bluetooth or Zigbee: Those are short-range (meters). LoRa is long-range (kilometers).
Why 915 MHz?
The 902–902 - 928 MHz ISM band is the North American LoRa mesh standard because it is unlicensed under FCC Part 15, has better building and vegetation penetration than 2.4 GHz, has a low ambient noise floor, and yields practical antenna sizes (~8 cm quarter-wave).
The fundamental tradeoff
LoRa’LoRa's extreme range comes at the cost of speed. A 50-byte text packet takes several hundred milliseconds to transmit. This is fine for messaging and GPS tracking —- and impossible for voice, video, or large files. Design your use case around this constraint and LoRa delivers remarkable results.