Sigfox

Direct Answer

Sigfox is a proprietary, global Low-Power Wide-Area Network (LPWAN) protocol developed by Sigfox (now UnaBiz). Operating in unlicensed sub-GHz ISM bands (868 MHz EU / 902 MHz US), it utilizes Ultra-Narrowband (UNB) modulation with a microscopic 100 Hz channel bandwidth to transmit tiny 12-byte payloads over extreme distances with ultra-low power.

Source: UnaBiz / Sigfox Global Network Specifications · Last reviewed Aug 28, 2026

Specs

Modulation Scheme	UNB (Ultra-Narrowband) DBPSK uplink / GFSK downlink
Channel Bandwidth	100 Hz (Europe) / 600 Hz (US)
Frequency Bands	RC1 (868 MHz EU), RC2 (902 MHz US), RC3 (Japan), RC4 (Latin America/APAC)
Uplink Payload Limit	12 bytes per message
Daily Message Cap	140 messages/day per device (ETSI 1% duty cycle limit)
Transmission Data Rate	100 bps (EU) / 600 bps (US)
Typical Range	10 km (urban) / up to 40–50 km (rural line-of-sight)

Ultra-Narrowband (UNB) Physics

While LoRa spreads a signal across 125 kHz, Sigfox concentrates RF energy into an ultra-narrow 100 Hz slice of spectrum. This extreme spectral density provides exceptional resistance to in-band noise and yields link budgets up to 160 dB. When an endpoint transmits, it broadcasts its 12-byte payload on three distinct randomized frequencies sequentially (spatial, temporal, and frequency diversity) without listening for a clear channel (ALOHA protocol).

Public Network Model vs LoRaWAN

Unlike LoRaWAN, which allows private individuals or enterprises to install private gateways and run autonomous network servers, Sigfox operates as a centralized global public telecommunications utility (operated by licensed national partners). Endpoints require subscription contracts per device to access national base station networks.