What is LoRa Radio?
LoRa stands for Long Range. It’s a proprietary radio modulation technique developed by Semtech, now widely available in cheap, mass-produced chips. It sits in the unlicensed radio spectrum (868 MHz in Europe/UK) and is specifically designed for long-range, low-power communication at low data rates.
Why LoRa Works So Well
Standard radio trade-offs look like this: more power means more range, but also more battery drain, and more congestion on the spectrum. Wi-Fi, Bluetooth, and mobile all sacrifice range for speed. LoRa makes the opposite choice.
Chirp Spread Spectrum (CSS) is the key. LoRa encodes data by sweeping (chirping) across a range of frequencies. This spread-spectrum technique makes signals highly resistant to noise and interference — a LoRa signal can be decoded even when it’s 19.5 dB below the noise floor. In practice, that means it can travel enormous distances at extremely low power levels.
Typical LoRa Specifications
| Parameter | Value |
|---|---|
| Frequency (UK) | 868 MHz |
| Maximum transmit power | 25 mW (14 dBm) |
| Typical range (flat ground) | 3–10 km |
| Typical range (line of sight) | 15–100+ km |
| Data rate | 0.3 – 50 kbps |
| Battery life (per device) | Days to months |
These are for reference — real-world performance varies significantly based on terrain, antenna quality, and node placement.
Why 868 MHz Matters for Scotland
Radio wavelength determines how signals behave around obstacles. Lower frequencies diffract more — they bend around hills slightly and penetrate buildings better. 868 MHz hits a useful middle ground: it diffracts more than 2.4 GHz Wi-Fi (which barely goes around corners) and travels much further than higher frequencies at the same power.
In Scotland’s open terrain — moorland, coastline, open water — 868 MHz LoRa with a well-placed antenna performs exceptionally. Line-of-sight links between elevated structures can achieve 20–50km with a standard 25mW transmitter. That’s not exceptional hardware. That’s physics.
The No-Licence Requirement
In the UK, 868 MHz is part of the ISM band — unlicensed radio spectrum. Anyone can operate a LoRa device without an amateur radio licence, provided they stay within power limits (25mW) and duty cycle restrictions (typically 1% — a brief transmission once per 100 seconds).
Meshtastic is designed to operate within these limits by default. The firmware manages duty cycling automatically. You don’t need any licence to use or deploy a Meshtastic node.
LoRa vs. Other Radio Options
| Technology | Range | Power | Licence? | Data |
|---|---|---|---|---|
| LoRa/Meshtastic | 10–100km | ~25mW | Not needed | Text/GPS |
| PMR446 Handsets | 1–5 km | 500mW | Not needed | Voice |
| Amateur VHF/UHF | 5–50km | 1–50W | Yes (M0) | Voice/Data |
| Amateur HF | Global | 100W+ | Yes (M0) | Voice/Data |
| Satellite (SPOT/Garmin) | Global | Medium | Subscription | Text/GPS |
For community-maintained text and GPS coverage across Scotland’s terrain, LoRa/Meshtastic is the only option that combines no-licence, low power, and genuinely long range.