Deutsche Telekom (DT) has implemented a trial in Germany to study the performance characteristics of a narrow band Internet of Things (NB-IoT) standard in licensed cellular spectrum using Huawei equipment. The trial used commercial base stations, which have been given a software upgrade in order to make them NB-IoT capable. NB-IoT is being looked at to enable low power wide area networks (LPWAN) for IoT using licensed cellular spectrum.
NB-IoT, sometimes referred to as narrow band cellular IoT (NB-CIoT) to distinguish it from existing LPWAN standards using unlicensed spectrum (Sigfox, LoRaWANs, Weightless, etc), is one of the options being looked at to use 4G LTE for LPWANs.
The requirements for LPWANs are very different from the original 4G standard, which was designed for high power, high speed, high throughput data transmissions, so the 4G standard has to undergo considerable alterations to make it suitable. LPWANs need very low cost devices (less than $5, more probably less than $2), a battery life of 10 years plus and for some applications an increased range of 20 db compared with existing cellular standards.
There are two main approaches to providing a suitable cellular LPWAN standard. The standards body 3GPP is working to adapt the existing LTE standard to make it suitable for LPWANs and has published definitions for Cat-1 and more recently Cat-0, which has a peak rate of 1Mbps for both downlink and uplink, half duplex capability and one antenna.
This will be followed by Cat-M in Q1 2016, which will provide 200Kbps peak rates, half duplex and a modem, which is 75% less complex (and costly) than the current Cat-1 devices – modules for which have just recently come to market. Cat-0 will not be commercially available until 2017 and Cat-M in 2018.
The alternative approach is the so-called ‘Clean Slate’ one, as advocated by Huawei in its white paper, Introduction to ‘Clean Slate’ Cellular IoT radio access solution, which argues that it is very difficult to meet the necessary LPWAN criteria by trying to adapt the existing LTE standard. It is better to start from scratch, therefore. Huawei’s NB-IoT allows for network deployment with only 200 KHz spectrum and a 20dB coverage gain compared to existing cellular-based solutions.
Ericsson, Nokia and Intel proposed a similar approach again in their 2014 white paper, LTE Evolution for Cellular IoT, narrow band LTE (NB-LTE), which essentially involves a software upgrade that allows mobile network operators to use their existing infrastructure.
In the field trial which took place on its local network in Bonn, Germany, DT and Huawei said they were able to evaluate the capabilities of NB-IoT under real commercial conditions and test the usability of NB-IoT for a first application to provide a smart parking to selected users. The field trial focused on verifying the performance of the technology in a variety of challenging, actual deployment scenarios.
"Deutsche Telekom is an innovation leader and we are the first company in Europe, and one of the first companies worldwide, to have enhanced our commercial network to be capable to communicate with sensors", says Bruno Jacobfeuerborn, Chief Technology Officer, Deutsche Telekom. “We support the adoption of solutions for cellular-based IoT technology that are based on worldwide standards and not proprietary ones.”
"NB-IoT can be deployed by software upgrade SingleRAN network, which significantly reduces network deployment costs. This mode is favourable for smart terminals sharing small amounts of data for a long time“, said David Wang, president of Huawei Wireless Network.
See also: In search of the low-power wide area network standard for IoT