Low‑Power, Wide‑Area (LPWA) Networks: A Comprehensive Overview

Low‑Power, Wide‑Area (LPWA) networks have emerged as the leading solution for connecting IoT devices. However, the terminology can be confusing. This article reviews key LPWA technologies and the companies behind them.

LPWA aims to link IoT sensors to the internet while avoiding cellular costs, Wi‑Fi power consumption, and Bluetooth’s limited range.

While LPWA devices consume more power during transmission than Bluetooth—often tenfold—‘low‑power’ refers to their architecture, which lets them stay asleep over 99 % of the time. With idle currents measured in microamps, many systems can run for years on a single battery.

‘Wide‑Area’ more precisely denotes a high link budget. LPWA’s impressive range results from enhanced receive sensitivity at both ends, enabled by very low data rates and sophisticated processing‑gain techniques.

Multiple‑access schemes allow numerous devices to share the same gateway simultaneously, though each LPWA technology employs a distinct approach.

We examine each technology in terms of:

• How high receive sensitivity is achieved.
• The multiple‑access scheme.
• Key strengths.
• Key weaknesses.
• The business model.

Understanding the business model is crucial—some companies provide networks, others sell technology, and some do both.

Sigfox

Sigfox, now nearly a decade old, pioneered the LPWA market. In the United States it operates as a network provider, while in other regions it supplies technology to carriers.

• Its base stations use an FPGA‑based channelizer to detect low‑bitrate DPSK transmissions across hundreds of potential channels.
• End nodes repeat the same 12‑byte message three times on three distinct frequencies, increasing the likelihood of successful reception.
• Downlink is theoretically possible, but limited because the base station must be off‑air while transmitting, raising the chance of missed traffic.
• The simplicity of the protocol allows a variety of RF transceivers, giving customers multiple supply options.
• Use cases are restricted to very simple IoT payloads, as each transmission carries only 12 bytes.
• Firmware updates or control applications are not feasible over Sigfox.
• In the United States, FCC time‑on‑air limits (400 ms) reduce Sigfox’s link budget by roughly 9 dB compared to Europe, and higher interference in the 900 MHz band further degrades performance.

WAVIOT

• WAVIOT, a Russian company, offers technology that is virtually identical to Sigfox but does not provide network services.
• Unlike Sigfox, any customer can purchase WAVIOT hardware to build a private solution.
• The technology uses a hopped signal that gives it a higher link budget than Sigfox for FCC‑compliant US applications.
• Base‑station equipment is expensive because it requires a large FPGA to implement all DPSK channels.

LoRaWAN

• LoRaWAN builds on the LoRa physical layer, whereas competitors such as Link Labs’ Symphony Link implement a different protocol with advanced features.
• LoRa offers superior receive sensitivity at the end node, resulting in a more balanced link budget compared to Sigfox.
• Like Sigfox, LoRaWAN employs an asynchronous, Aloha‑style access scheme, which imposes similar downlink constraints.
• For deeper insight, read our LoRaWAN considerations guide.
• The business model is complex: Semtech sells the LoRa PHY, the LoRa Alliance develops the protocol, and several operators are testing carrier‑grade networks.
• Carrier and private LoRaWAN deployments can interfere with one another.

LTE‑M1

• LTE‑M delivers the power efficiency of LoRaWAN or Sigfox while offering LTE‑grade data rates and feature sets. Learn how LTE‑M improves power profiles in our LTE‑M power guide.
• Using LTE‑M requires a subscription to a cellular operator.
• Device certification on carrier networks can be expensive.
• LTE‑M1 networks were slated for US rollout in 2017.
• Pricing is expected to be competitive with Sigfox.

NB‑IoT

• NB‑IoT (also known as LTE‑M2) is a 3GPP technology finalized recently, distinct from LTE‑M1 but deployable within LTE spectrum or in guard bands.
• It was designed to fit within legacy GSM 200 kHz blocks, and many European and Asian operators plan to deploy it for IoT.
• Sigfox’s market proof helped carriers see the business potential for NB‑IoT.
• NB‑IoT lags LTE‑M1 by about a year; networks are expected to appear by late 2017 or 2018.
• As with LTE‑M1, using NB‑IoT requires paying a carrier and obtaining device certification.

Ingenu

• Ingenu, formerly Onramp Wireless, operates its own 2.4 GHz DSSS network.
• Its link budget is strong, but the DSSS endpoint modem consumes more power than LoRa‑based solutions.
• Ingenu’s focus is on being an IoT network provider rather than a pure technology vendor, similar to LTE‑M or NB‑IoT.
• Its network is deployed in only a few cities as of now.
• It will be interesting to see how Ingenu fares against large LTE‑M rollouts from carriers like AT&T and Verizon.

In summary, the LPWA landscape offers a range of options. For off‑the‑shelf technology, consider Symphony Link, which remains the most advanced LPWA solution outside of LTE‑M.

Download our whitepaper for a deeper dive into LPWA technologies: