The 5G standard, developed by the 3rd Generation Partnership Project (3GPP), which includes the European Telecommunications Standards Institute (ETSI) and China Communication Standards Association (CCSA), introduces New Radio (NR). Erik Ekudden, Group CTO at Ericsson, explained that defining NR is a key focus in the first release. In this case, rather than introducing a new modulation and coding scheme, the 3GPP targeted the IoT and connected environments.
“The main focus this time has been on flexibility to support a large range of devices and services with vastly different characteristics, different types of deployments and frequency allocations that range from below 1 GHz well up into the mmWave bands,” he wrote.
The inclusion of the NR standard will enable Ultra-Reliable Low Latency Communications (URLLC) Antenna systems, beam forming and energy efficiency have also been addressed to support the significant growth in data volume, from connectivity and machine intelligence, which 5G is expected to bring.
In this connected future, with smart homes, workplaces and cities, it will not be a case of one-size fits all. Self-driving cars, for example, will be processing a lot of data from multiple sources, whereas smart meters or a network of sensors in a building will not require such heavy data processing.
For these tasks, Low Power Wide Area Networks (LPWANs) will be used – Narrow Band Internet of Things (NB-IoT) or Long Range (LoRa)-based WANs. Both are low power standards, the first is a radio technology, standardised by the 3GPP, the second is based on Semtech’s LoRa IP and curated by the LoRa Alliance.
Richard Landsdowne, Senior Director of LoRa Cloud Services at Semtech, explains that LoRa-enabled silicon is the physical layer, and LoRaWAN is the protocol standard that defines the product. “[The standard] is simple and lightweight, so that it can be used with the simplest, lowest power device,” he said. The network operates on an unlicensed Industrial Scientific and Medical (ISM) sub-1GHz spectrum which is free for operators and device manufacturers to access.
The principle is based on simple energy technology; the worse the signal on a phone is, the more it drains the battery, so by controlling the range and the data rate, the LPWAN can send data further by sending it slower. LoRaWAN has a data rate of around 293bit/s to 50kbit/s, depending on the distance of the sensor from the gateway. NB-IoT runs at around 250kbit/s.
LPWAN has improved mobility between networks, continued Landsdowne.
“Unlike cellular systems which are operated by GSM (Global Systems for Mobile communications) members, and users have to attach to a network when they move from one region to another. LoRaWAN operates one-to-one, to help the portability of devices between network operators,” he explained. “With cellular networks, different operators own the spectrum and different areas will have different frequencies and channels. It is not possible to transmit without permission. LoRaWAN is unlicensed, so you can build your own network.”
LoRaWANs can therefore be installed in public, private or hybrid networks indoors and outdoors. Landsdowne likens installation to adding a Wi-Fi box. LoRaWAN signals can cover up to 30 miles (48km) per gateway in open environments. Transmission current is 18mA at 10dBm and 84mA at 20dBm allowing for use with devices that can be powered by coin cell batteries. NB-IoT sensors consumer 220mA at 23dBm and 100mA at 13dBm.
A city council can use LoRaWAN to create a network for a smart city. Landsdowne cites a project that is in its infancy – waste collection. Sensors in bins can transmit when the bin is full, so the council only collects ones that are full. Another example of long battery life is smart parking. It is estimated that 15% of traffic on the roads is made up of cars looking for somewhere to park. Spaces with sensors, linked to a booking app on a smartphone can reduce congestions and pollution.
LoRaWAN has been built from the ground up for the IoT, explained Landsdowne. Revision 1.01 and 1.02 included the ability to join a server. A LoRa device can join the network by sending a request. “The whole standard is based on things being asleep,” he joked. The device assumes someone/something is listening and sends a join request.
Once it receives the security log, it goes back to sleep. The fact that the device does not have to wake up each hour contributes to the low energy consumption, compared with devices that send a signal each hour to ‘check in’.
Devices may be in the field for 10 to 20 years, and updates will be necessary. Maintenance or service updates can be expensive in terms of capital equipment and labour. Over-the-air software updates are the standardised – and cost-effective way - to update, Landsdowne believes. Later standards will allow people to connect multiple networks or services and update them, he added.
Like Wi-Fi, the LoRa frequency is open. NB-IoT, however, is based on Intel’s NB-LTE technology and technology from telecoms giants Huawei, Nokia and Ericsson. Users purchase connectivity or bundle services from licensed members to cover a specified area.
Using the LTE cellular infrastructure restricts NB-IoT to outdoor, public networks with which it maintains a synchronous connection.
NB-IoT is designed for machine connectivity and is focused on Industry 4.0 applications, said Phil Evans, UK Head of TUV SUD’s Telecoms Group. The group provides testing services, product certification and qualification across industries which include transport, medical and manufacturing. It is deployed within the LTE spectrum and can use frequency resource blocks within a conventional LTE carrier or it can use unused frequency in the guard band between radio bands. The guard band is designed to prevent interference between devices when they are transmitting simultaneously.
According to Rohde & Schwarz’s market segment manager, IoT, Feng Xie, the 3GPP standard, from release 13 will dedicate standards address machine communication, developing and defining features. In a tutorial, he revealed that in release 14, there is a defined maximum transmission power and in release 15, there will be wake-up signal and early data transmission to address the power consumption for IoT devices.
The standard requires 200kHz bandwidth and can therefore run next to existing cellular networks, to benefit from that network’s security and privacy features. This also extends to security measures inherited from LTE, for example the SIM card and embedded security garnered from 2G, 3G and 4G networks.
There are examples of LoRaWANs around the world, from keep track of bicycles in Amsterdam to a smart city pack offered by a South Korean telecomm operator. The LoRa Alliance reports that there are 83 public networks operating in 49 countries around the world. Adoption in the UK is sluggish, although Landsdowne reported that there are small and private LoRaWANs and that the Scottish National Executive has approved LoRaWAN for all public services and hospitals in Scotland.
According to the GSM Alliance, 40 countries are expected to roll our NB-IoT networks in the near future.
Estimates of how many connected devices will be installed varies wildly, from around 13bn to over 75bn in five years’ time. There is agreement that the IoT will continue to grow and that 5G technology will support that growth. New products and services will be developed which could impact edge, cloud and data centres. While N-IoT and LoRaWAN jostle for position, a global, scalable approach is likely to see the most success for operators and consumers.