What Is NB-IoT NarrowBand Internet of Things?

NB-IoT is a standards-based LPWAN that enables a range of new IoT devices and services. In some cases, it reduces power consumption and improves system capacity and spectrum efficiency, especially in deep coverage, remote, and hard-to-reach locations.

NB-IoT also minimizes device complexity. The underlying technology is much simpler than GSM/GPRS and can co-exist with 2G, 3G, and 4G mobile networks.

Today, cellular gateways are frequently used to aggregate data from many sensors and send that information to the server. NB-IoT devices, however, can send data directly, eliminating the need for a cellular gateway and the costs associated with it.

However, because NB-IoT does not operate within the LTE band, providers often incur higher deployment expenses which, if passed along, could negate any cost advantages. In fact, depending on the network operator, connectivity costs per MB can be double that of 2G/3G/LTE CAT1 connectivity.

Is NB-IoT the Best Solution for Your IoT Program?

While NarrowBand Internet of Things (NB-IoT) has been gaining traction as the leader in next-gen IoT connectivity, alternatives like CAT-M provide benefits that may actually be better suited for many use cases. NB-IoT may be a viable option for utilities, smart cities, agriculture, and manufacturing applications. But vendors are advised to thoroughly evaluate NB-IoT as well as competitive technologies to ensure they’re choosing the best one for their specific needs.

The Key Benefits of NB-IoT
Lower Device Manufacturing Costs

NB-IoT protocols feature much simpler construction. Using chipsets specifically engineered for them reduces the connectivity component cost, which lowers the cost of the overall device. Further reductions are anticipated as popularity increases.

Security and Reliability

Because it operates within a licensed spectrum, NB-IoT features guarantee quality of service which ensures reliability. It also benefits from the security features of mobile networks, including device identification, user privacy, authentication, and data integrity.

Stronger Coverage

Whether the device is used indoors or out, above ground or below, or deep within an urban environment, it should provide sufficient coverage—even when power sources are unavailable.

Power Efficiency

Due to its simpler waveform and the fact that the device disconnects when not collecting and sending data, battery lifetime expectancy can be as high as ten years.

Scalability

Through its ability to support large numbers of devices over a wide geographic area, millions of devices could potentially connect via a single deployment.

Simple Implementation

By installing on current networks and leveraging existing cellular infrastructures, NB-IoT integrates relatively easily into a mobile operator’s existing IoT platform.

The Limitations of NB-IoT
Limited Data Transmission

With the ability to transmit less than a kilobyte of data per day—the equivalent of a text message—voice or video transmission is not an option. The NB-IoT data upload rate is about 20Kbps, which is low compared to competing technologies. Its bandwidth is about 200 KHz. Carefully consider the data requirements of the device you’re developing.

Limited Device Mobility

NB-IoT devices will remain connected only within a finite environment and only to a single network operator. This could mean limitations for uses like wearables that leave a designated perimeter. If the device enters another country, it’s at risk of becoming unusable if the operator has no local presence there.

Inflated Marketing

NB-IoT was designed to meet many specific device requirements. But its purported range of potential applications may be increasing faster than the technology is actually evolving. Beware of unsubstantiated or unverifiable claims. Understand what it’s capable of today, and what’s scheduled for the future.

Lacking Proof of Concepts

Commercial roll-outs have been relatively limited, so a clear picture of success is difficult to find.

Data Costs

Connectivity costs are typically higher than 2G/3G/LTE CAT1 pricing, placing additional limitations on the use of the device.

There are several alternatives that may be better suited to provide the functionality required for your device’s specific use cases. Among the most common is LTE-M.

LTE-M (CAT-M): Alternative to NB-IoT

“We analysed three key KPIs including coverage, cost and power consumption. While the market perception is that NB-IoT has a clear advantage over CAT-M1 for these KPIs, we conclude that CAT-M1 actually offers advantages for coverage and power, and only a minimal cost disadvantage when compared to NB-IoT.”

—Iot-now.com

LTE-M is an alternative LPWAN technology also built to support a longer device lifespan. As with NB-IoT, by allowing the device to sleep when not in use, its battery can last for years. LTE-M can co-exist with 2G, 3G, and 4G and also deliver the benefits of mobile networks—mainly security and privacy features.

However, because LTE-M is compatible with the existing LTE network and uses existing LTE base stations, device mobility isn’t a problem. This could make it better suited for some applications.

Unlike NB-IoT, LTE-M allows for higher data rates, which is important for more data-rich use cases. And bandwidth optimizations can be used to achieve the same in-building and rural coverage as NB-IoT. LTE Network compatibility also means new antennas aren’t required—carriers simply need to upload new software.

When Should Organizations Consider NB-IoT?

Each IoT device has its own unique set of requirements. The connectivity option that’s perfect for one may be entirely wrong for another. The good news is, there are many to choose from. The first step is to ensure you have a thorough understanding of your requirements. NB-IoT might be the best option if your device:

  • Is likely to be placed in remote, underground or hard-to-access locations.
  • Will remain stationary.
  • Will not require the high-bandwidth necessary to transfer large amounts of data, including large files, voice or video.
  • Will require very long battery life.
  • Will be part of a massive network of sensors.
What Is LPWAN Technology?

Organizations looking to reduce the manufacturing and lifetime operating costs of an IoT device, often consider Low-Power Wide-Area Networks (LPWANs) like NB-IoT and LTE-M. LPWANs are a class of IoT connectivity solutions that share common characteristics: They require less power, have extended operating ranges and typically can transmit up to a kilobyte of data per day.

LPWAN technologies work best when devices are located underground, in remote areas, or deep within urban infrastructures. Without LPWAN, these devices would require transmitters that use excessive amounts of power to operate and therefore quickly drain their batteries. Primary applications for LPWAN might include smart lighting, smart grid, water metering, gas detectors and smart agriculture.

For more information about NB-IoT as well as alternative technologies that might be a better fit for your project, contact an Arm salesperson.

For a webinar on NB-IoT, register here.

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