A Comparison of LPWAN Technologies

A Competition Between LoRaWAN, Mioty, NB-IoT, LTE-M and Sigfox

LPWAN Interview

Data networks that link thousands of sensors via a gateway and enable the reliable transmission of machine status or environmental data are implemented every day using one of several LPWAN technologies. Without these Low Power Wide Area Networks, the vision of the Internet of Things would not yet be a reality.

RFID & Wireless IoT Global spoke to LPWAN expert Wolfgang Weber, former Global Industry Manager at Pepperl+Fuchs, about the individual LPWAN technologies and the status of LPWAN network expansion.

For further information, please contact Daniel Möst, New Business Development Manager, Pepperl+Fuchs.

Technology story powered by: Think WIOT and Pepperl+Fuchs

For further information, please contact Daniel Möst, New Business Development Manager, Pepperl+Fuchs.

LPWAN-based M2M connectivity enables IoT devices to perceive and interact with the environment, anywhere and at any time.

LPWAN is considered a fundamental technology for the Internet of Things.

The abbreviation LPWAN stands for Low Power Wide Area Network. LPWAN has properties that enable companies to optimally implement their objectives in the Internet of Things (IoT). The German term 'Niedrigenergweitverkehrnetz' sounds rather difficult, so the English abbreviation LPWAN has become established. LPWAN stands for network protocols that connect low-energy devices such as battery-powered sensors to a server.

The network consists of end devices called nodes and gateways that act as base stations. The gateways forward the data collected from the end devices to the network server for evaluation. The end devices are thus controlled by the network server.

The physical connection between end devices and gateways can be established via license-free frequencies or mobile radio frequencies. LPWAN is available on the market both in the unlicensed spectrum (LoRaWAN, Sigfox and Mioty) and as cell-based narrowband technology (NB-IoT, LTE-M).

Advantages of the LPWAN Network Protocol

Low energy consumption by end devices
Long communication range
License-free usage
Efficient bandwidth utilization
Simplified network topology
Scalability of the network and capacity expansion
Low acquisition, installation and operating costs
Robustness for M2M communication

LPWAN technologies that are actively represented on the market in Europe include NB-IoT (Narrowband-IoT), LoRaWAN (Long Range Wide Area Network), Sigfox, Mioty and LTE-M (Long Term Evolution for Machines).

In Germany, the use of LoRaWAN, NB-IoT and LTE-M is predominant. Mioty is relatively new. Sigfox is represented throughout Europe, particularly in its country of origin, France.

1. Mr. Weber, how long have you been involved with LPWAN technologies?

Wolfgang Weber: I have been working with LPWAN since 2015. Back then, the city of Heidelberg approached Pepperl+Fuchs as part of a smart city project. We supplied the sensors for this project.

2. Which applications does Pepperl+Fuchs implement with LPWAN technologies?

Weber: We primarily use LoRaWAN technology in sensors for measuring fill levels and distances in liquids, solids, glass and other materials.

We also use LoRaWAN in the field of ultrasonic sensors. We are one of the world's largest producers of these sensors for industrial automation.

Ultrasonic applications are a broad field. We only cover part of the field of industrial applications. Our ultrasonic sensors do not transmit via radio in 99.99 percent of applications. LPWAN is a new application in this field with a comparatively small number of units.

3. Does the development of recent years correspond to the general expectation of LPWAN technologies?

Weber: From a technological point of view, yes. The technologies are fully developed and suitable for many low-energy applications. Each of the LPWAN technologies enables battery operation for 10 years or more.

However, in terms of market penetration, there were greater expectations for LoRaWAN. The number of implementations has not developed according to our expectations.

This certainly has to do with the requirements for the IT structure, which turned out to be very complex. Although data collection works very well, using the data afterwards poses many challenges. It will be several years before this is resolved.

4. Do you see the future of LPWAN at risk because of this?

Weber: No, not at all. We should and will stick with LPWAN and find further opportunities to create solutions with it. The business model on which the application is based will also be decisive for its success.

LoRaWAN

LPWAN-based M2M connectivity enables IoT devices to perceive and interact with the environment, anywhere and at any time.

Image: Thermokon Sensortechnik GmbH – www.thermokon.de

The LoRaWAN protocol controls communication between battery-powered LoRa devices and gateways. LoRaWAN networks function wirelessly and fulfill one of the central requirements for IoT technologies. In Europe, the frequency band from 433.05 to 434.79 MHz (ISM band region 1) and from 863 to 870 MHz (SRD band) is approved for LoRa communication.

In North America, the frequency band from 902 to 928 MHz (ISM band region 2) is available. The frequency spread, based on the Chirp Spread Spectrum modulation, enables high efficiency in data transfer and low energy consumption. At the same time, the modulation used minimizes interference.

Communication from the end device to the gateway and to the application server is encrypted on two levels. Firstly, the protocol level from the end device to the network server, and secondly, the data level (payload) from the end device to the application server (end-to-end).

The History of LoRaWAN

The development work that ultimately led to LoRa began in France in 2009. The founders of LoRa used Chirp Spread Spectrum (CSS) modulation technology, a technology that is widely used in the maritime industry for sonar devices and in aviation for radar devices.

LoRa is actually just a combination of the two English words ‘Long’ and ‘Range’, but was nevertheless registered as a trademark by Semtech in 2012. LoRa therefore stands for ‘long range’.

1. Which key technological data stands out in comparison with other LPWAN technologies? What do users need to consider?

Wolfgang Weber: LoRaWAN is classified as the LPWAN technology with the longest data transmission range. In urban areas, data can be transmitted up to 2 kilometers with one device and one gateway. This is partly due to the high building penetration. In rural areas, there is often talk of a range of up to 15 kilometers.

Users must bear in mind that the general technical key data does not provide any information about what a LoRaWAN network can achieve in a specific application.

The topography at a project location usually has a major influence on the range. When it comes to flood protection in valleys, for example, the limits of any radio technology are quickly reached.

2. What advantages and performance would you attribute to LoRaWAN technologies?

Weber: In my opinion, the biggest advantage is that LoRaWAN is license-free. This does result in some restrictions, for example in the frequency of data transmission. However, the acquisition costs for LoRaWAN are low and network access is easy with the appropriate hardware. Companies can become network operators themselves.

Furthermore, no SIM cards are required. This results in flexible scalability, which LoRaWAN was also designed for. Large IoT deployments, where thousands of devices are networked with a manageable number of gateways that monitor multiple channels and process multiple messages at the same time, can be set up easily

3. How far has the network construction progressed?

Weber: Nationwide LoRaWAN networks have now been set up in the Netherlands, Switzerland and in South Korea. In Germany, the number of applications is increasing. The Rhine-Neckar region, with Heidelberg and Mannheim, has one of the largest LoRaWAN networks in Germany.

More are in the pipeline. The energy provider SH Netz in Schleswig Holstein, for example, has decided to set up a nationwide LoRaWAN network in the district of Rendsburg-Eckernförde in 2023.

It will primarily be used for smart city applications such as smart parking and smart waste. These are just a few examples. Hundreds of other LoRaWAN applications are already in use.

4. For which applications is LoRaWAN suitable?

Weber: LoRaWAN is always suitable when access to power and data lines is not available or would be too costly to provide because the location is difficult to access or very remote. Due to the excellent object penetration, smart city applications such as those already mentioned, the recording of meter readings and environmental sensor data and lighting control are now typical areas of application. In the industrial environment, LoRaWAN can be used for machine condition monitoring and predictive maintenance.

5. What disadvantages are associated with this technology?

Weber: : The maximum file size must not exceed 51 bytes. LoRaWAN is therefore not suitable for transmitting large amounts of data. In addition, the license spectrum may only be used one percent of the time, i.e. only 36 seconds per hour. A further restriction for applications is the dependence on terrestrial connections. However, solutions can be found for this in connections with satellite combinations in the 2 GHz spectrum.

NB-IoT

NB-IoT is a mobile radio-based LPWAN that runs in the licensed frequency band spectrum. NB-IoT uses only (narrow) 200 KHz of the available (wide) bandwidth. NB1, standardized in 2016, transmits up to 66 kbit/s in the uplink and 26 kbit/s in the downlink. NB2 from 2017 achieves 159 and 127 kbit/s respectively. This makes it ideal for transmitting the small amounts of data produced by simple sensors and tracking devices.

NB-IoT is a 3GPP industry standard that uses existing network infrastructure such as sites, base stations, antennas and backhaul in the licensed spectrum. Since NB-IoT uses LTE security mechanisms based on the specifications of the 3GPP standard, a SIM card is always required to use NB-IoT. The use of a standardized SIM profile also enables international use.

NB-IoT roaming is available in all European countries. Cross-border applications are possible between the networks of the participating mobile network operators. These include the networks of Deutsche Telekom in Germany, the Netherlands, Austria, the Czech Republic, Slovakia, Hungary, Greece, Poland and Croatia; the networks of Swisscom in Switzerland and Liechtenstein, as well as Telia Company in Denmark, Finland, Norway and Sweden; and the networks of Vodafone in Spain, Italy, Germany, the Netherlands and the UK.

NB-IoT is a high-performance LPWAN radio technology standard developed by 3GPP for mobile network devices and services.

The application areas for NB-IoT present typical application scenarios for LPWAN.

1. What characterizes NB-IoT?

Wolfgang Weber: The energy-efficient capture and transmission of small amounts of data is also handled exceptionally well by NB-IoT networks. There is no limit to the number of participants in the network or per radio mast. As with other LPWAN technologies, the transmission range here is also very long, at up to 10 kilometers. Of course, it can be much shorter in individual cases.

2. What advantages and performance would you attribute to this technology?

Weber: Like all LPWAN technologies in the licensed spectrum, NB-IoT has a higher transmission frequency than LoRaWAN and enables the transmission of larger amounts of data.

At the same time, the performance is still so energy-efficient that battery operation of 10 years can be expected. This LPWAN is also characterized by its high reliability, which is based on the repetition of transmissions. This ensures that a signal actually reaches the receiver.

3. How far has the NB-IoT network construction progressed?

Weber: Data on this should always be viewed with caution, as it is not really about areas, but about the number of subscribers that can be reached. We know how many dead spots there still are, despite alleged 98 percent coverage in the mobile network.

4. For which applications is NB-IoT suitable?

Weber: The application examples for NB-IoT are many and varied. There is an opportunity to benefit from NB-IoT wherever things can be networked with each other. Smart city applications are again the first to be mentioned here, but also: transportation & logistics, production & industry, and applications in agriculture and security technology.

NB-IoT is also suitable for localizing objects, people or animals. Furthermore, due to the slightly higher transmission power, body-worn sensors and wearables can also be operated with NB-IoT.

5. What disadvantages are associated with this technology?

Weber: Use in the licensed spectrum results in costs that are not incurred with license-free LPWAN technologies. In addition, the technology itself has a number of disadvantages.

This LPWAN technology does not offer an optimal solution for higher data requirements. Furthermore, the latency with NBIoT can be up to 10 seconds. In conjunction with the low transmission rate, this means that NB-IoT devices transmit more frequently and therefore have a slightly higher power consumption.

The dependence on the mobile network results in a further disadvantage: if regional or national network operators have not concluded roaming agreements for NB-IoT, network use must be restricted to the region.

6. What is your final assessment?

Weber: NB-IoT is a reliable LPWAN technology. It is currently on the upswing and will continue to grow. At Pepperl+Fuchs, we are noticing this in the increasing number of project inquiries for NB-IoT.

Sigfox

Sigfox connects a wide range of industries and operates many IoT networks in Europe.

Sensor data of all kinds is transmitted to the gateway and from there to the Sigfox Cloud.

Sigfox stands for a license-free UNB (Ultra-Narrow-Band) technology signal with a bandwidth of only 200 kHz. The technology uses the 868 MHz or 902 MHz frequency ranges. It is theoretically possible to achieve a nominal range of 30 to 50 kilometers for a Sigfox transmission in rural areas.

In densely built-up urban areas, three to ten kilometers can be achieved. The packet size for the uplink is limited to 140 messages of 12 bytes per day. The downlink packets are smaller and limited to four messages of eight bytes per day.

The History of Sigfox

Sigfox was founded in France in 2010. The first IoT networks were set up there. Sigfox refers to these networks as 0G networks. Sigfox operated as an independent network operator in Germany, France, Spain and the United States of America until 2020. Sigfox Germany was acquired by Heliot in 2020 and Sigfox France by Unabiz in 2022. Heliot Europe has been the exclusive operator of the global Sigfox 0G network in Germany, Switzerland, Austria, Slovenia and Liechtenstein since 2022.

This makes Heliot Europe the largest 0G network operator in Europe. Sigfox 0G networks are operated in 75 countries worldwide and are thus theoretically available to over 1.3 billion people. The 0G network operated by SigFox Germany achieves a nationwide coverage of 90 percent. Its customers and partners today include companies such as Deutsche Post DHL, Siemens, Weber Betonwerke, AlpsAlpine, ACP Digital and Box ID.

1. How does Sigfox differ from other LPWAN technologies? What do users need to consider?

Wolfgang Weber: Like all LPWAN technologies, Sigfox is also capable of implementing low-energy applications with low data transmission rates and small data packets over long distances. The maximum range of a data transmission is nominally 50 kilometers in clear view, which is extremely far.

Like LoRaWAN, Sigfox is a proprietary technology and, like LoRaWAN, operates in the license-free spectrum but, like NB-IoT, is offered by a network operator. There are various subscription models for billing the usage costs.

2. What advantages would you attribute to this technology?

Weber: Sigfox is suitable for mass use in the IoT. Millions of devices can transfer data to the Sigfox Cloud via a gateway. Its suitability for use in the Industrial IoT has already been proven several times by large logistics companies and industrial groups.

Another advantage is that the Sigfox network can be set up easily by the operator. There are no roaming charges for data transfer across national borders, which is also an advantage.

3. How far has the network construction progressed?

Weber: It is actually very advanced throughout Europe. In continental Europe, it is available everywhere, although not nationwide. According to a study by Fraunhofer IML, Sigfox has only been proven to be available in 10 out of 24 countries in Europe. [1]

4. For which applications is this technology suitable?

Weber: Like all other LPWAN technologies, Sigfox can generate great benefits in smart city applications. The most prominent applications can be found in tracking and tracing, i.e. tracking goods in the logistics sector (see DHL).

I am not aware of any applications in the waste disposal sector. Due to the very limited amount of data, I do not see any potential applications for sophisticated measurement technology. Temperature or CO₂ would certainly work.

5. What disadvantages are associated with this technology?

Weber: The fact that Sigfox is not yet available throughout Europe creates some restrictions. It is also a proprietary standard that only works with the Sigfox network. If customers want to change providers, they would need new end devices.

Mioty

Mioty was developed by researchers at Fraunhofer IIS and presented to the public for the first time in 2018. Mioty uses the license-free 868 MHz band in Europe and the 915 MHz band in North America. Firstly, it differs from other LPWAN technologies in that it is a software-based solution and can therefore be used independently of the hardware used.

Secondly, the development focus of the Fraunhofer researchers was on overcoming the susceptibility to interference of data transmission in free, unlicensed radio bands. The result is the Telegram Splitting Multiple Access (TSMA) data transmission method.

The basic idea of Telegram Splitting is not to send the data to be transmitted in its entirety, but to split it into several redundant sub-packets that are sent several times over different frequencies in the band. Only 50 percent of the packets need to be received correctly for a complete transmission. Collisions, including those caused by other Mioty devices, are no longer a cause of interference.

In the near future, more than 30 billion devices will be connected to the Internet. Mioty was invented to avoid interference during mass data transmission.

Large numbers of Mioty sensors can be operated on widespread industrial sites with just one base station.

1. What technical features stand out with Mioty?

Wolfgang Weber: Mioty has been developed to enable low-interference radio transmissions over long distances with many devices. Interference is generated both by other Mioty devices and by external devices transmitting in the same frequency range and is a particular problem when radio users want to scale. The transmissions of the different sensors can then generate interference.

TSMA eliminates this problem. From a technical point of view, the signal to be sent by the sensors is divided into many small sub-packets and sent by radio at different frequencies and with time intervals. On reception, the packets are reassembled into the original information.

The low self-interference makes it possible to receive up to one million transmitters simultaneously. The transmission range, which depends on various factors, is also very long with Mioty. It is nominally up to 15 kilometers.

2. How far has the network expansion at Mioty progressed?

Weber: Munich Airport, for example, measures temperature, air pressure and humidity precisely in many places and can thus improve its CO₂ energy balance. However, as Mioty is still relatively new, the nationwide expansion of the network is still in its infancy.

3. What disadvantages are associated with Mioty?

Weber: The initial installation costs are not as low as for licensed LPWANs. Users have to procure the base stations and end devices themselves. Finding a provider should not be difficult, but there are not yet many providers.

LTE-M

LTE-M was developed by 3GPP specifically for extensive machine-to-machine and IoT applications.

LTE-M, also known as CAT-M1, is an important LPWAN technology for bridging the gap between the existing LTE/4G network and NarrowBand IoT. It is considered the future-proof successor to 2G and 3G, whose networks are being dismantled worldwide. LTE-M is primarily predestined for the transmission of small and medium data volumes.

LTE-M was created in Release 13 of 3GPP as a supplementary standard to 4G/ LTE for eMTC (Enhanced Machine-type Communications). In terms of its basic structure, it is therefore designed for machine communication in the IoT. LTE-M works like LTE cellular, but the maximum data speed is limited to 1 MBit/s in order to save power and enable battery operation of the modules. The licensed frequency spectrum of the conventional 4G network at 800 MHz is used.

1. What technical possibilities can be achieved with LTE-M?

Wolfgang Weber: It transmits small amounts of data very reliably. The transmission power is slightly higher than that of other LPWAN technologies, but is low enough for battery operation. LTE-M is a bit like the more powerful "brother" of NB-IoT. Both use the existing mobile radio infrastructure. The maximum number of users that can be supported by an LTE cell is roughly estimated at over 10,000 active users per cell.

2. What makes LTE-M stand out compared to other LPWAN technologies?

Weber: Basically, it can be said that Cat M has a significantly higher bandwidth, a much higher data rate and lower latency compared to NB-IoT. This applies even more so compared to all other LPWAN technologies, as NB-IoT is already much more powerful.

However, the range is lower and the power consumption higher. How high, of course, depends on the amount of data being transmitted. And this can be much higher than both other technologies. Battery operation can then become problematic. I think the 20 kilometer range is unrealistic. It also does not match the data in the other chapters.

Basically, the following ranking applies to the ranges: LoRaWAN, NBIoT, LTE Cat M. Sigfox and Mioty are about the same with LoRaWAN. LoRaWAN still has a range of 15 kilometers in an open field, approx. 3.5 kilometers in urban areas and 1.5 kilometers in basements. NB-IoT and Cat M both fall short of this.

3. For which areas of application is it particularly suitable?

Weber: LTE-M is recommended for IoT applications with a large number of users. Production plants with hundreds of sensors that transmit machine status and process data are an ideal area of application. LTE-M is also particularly suitable for smart city, wearables, e-health and smart tracking applications.

4. How far has the network expansion for LTE-M progressed?

Weber: LTE-M is currently offered as a nationwide network in 17 countries in Central Europe. The core area of network coverage extends in a west-east arc from France in the west via the Benelux countries and Germany to Poland. In Germany, it is the IoT network with the largest flat coverage after NB-IoT.

5. What disadvantages are associated with LTE-M?

Weber: The biggest disadvantage is closely linked to the great strength of this IoT network. Because comparatively large volumes of data can be transmitted, the energy consumption here is higher than with other LPWAN technologies.

Weber: In order to save even more energy and thus enable a battery life of up to 10 years, 3GPP also codified NB-IoT as a standard in the same release that defined LTE-M.