SigFox Explained: Technology, Market Impact, and How It Compares to Link Labs

At first glance, it may seem unusual for Link Labs to discuss our biggest competitor. Yet analysts and customers alike are asking about SigFox’s recent $110 million fundraising round. Below is a concise overview of the news, its implications for the IoT market, and a detailed look at SigFox’s network and business model.

See also: Sigfox Resource Page

Ultimately, SigFox’s announcement validates the growth we anticipated when we founded Link Labs. It underscores the promise of the low‑power wide‑area (LPWA) segment—a niche within the broader machine‑to‑machine (M2M) market that today is commonly referred to as the Internet of Things (IoT).

What Is SigFox?

SigFox operates by installing antennas on existing cell towers, then collecting data from devices such as parking sensors, water meters, or simple alarm systems. The network uses unlicensed radio frequencies: in the U.S. the 915 MHz ISM band (similar to a cordless phone) and in Europe a narrower 868 MHz band. All regions have comparable bands, though regulatory rules vary.

Data transmissions are tiny—just 12 bytes—sent at a slow 300 baud rate. The protocol employs phase‑shift keying (DBPSK) for uplink and frequency‑shift keying (GFSK) for downlink. This low‑speed, long‑range design is grounded in information theory: slower transmissions are easier for the receiver to decode, allowing coverage of large distances.

Because of these characteristics, SigFox excels in scenarios that require occasional, low‑volume data, such as basic alarm systems, location tracking, and one‑way metering. Messages are typically retransmitted a few times to improve reliability, but battery life and delivery confirmation remain challenges.

SigFox has expressed interest in adding bi‑directional capability, akin to a smartphone. While the company has yet to launch a true two‑way network, success in this area would broaden the range of feasible applications, even though the link would still be asymmetrical.

Entering the U.S. market has presented regulatory hurdles. Under FCC Part 15, a transmission cannot exceed 0.4 seconds, whereas SigFox’s packets last about 3 seconds. This discrepancy forced a redesign of their architecture and slowed deployment. Additionally, U.S. frequency bands experience higher interference than those used in Europe, further complicating rollout.

In May 2014, pet‑tracking firm Whistle announced a partnership to deliver solutions over SigFox. However, the lack of a mature U.S. network stalled product launches, prompting Whistle to acquire cellular‑based tracker Snaptracks (maker of Tagg) a few weeks later.

How Does Link Labs Differ?

While SigFox and other LPWA players carve out their own niches, Link Labs has engineered a distinct technology stack that supports demand‑response grid control, asset tracking, commercial security, and more. For a deeper technical comparison, visit our Symphony Link page.

In short, the LPWA market offers tremendous opportunity. We welcome healthy competition with SigFox and look forward to defining the next generation of IoT connectivity.