When it comes to enabling the Internet of Things (IoT), low-power wide-area networks (LPWAN) are a key element of the big picture. Several different LPWAN technologies currently exist in the marketplace, and while there is no one-size-fits-all favourite and each is best suited to certain types of applications, NB-IoT (narrowband IoT) is emerging as one of the leaders.
We asked Mark Coxen, South African sales manager for Quectel Wireless Solutions, for his insights into how NB-IoT is shaping up.
Do you see NB-IoT as the frontrunner amongst the LPWAN technologies being rolled out?
There is much controversy around the LPWAN technologies in the South African marketplace, and not much information around the ‘who, where and what’ for this technology. The non-cellular technologies have made some inroads around the value-adds and benefits of utilising the specified technology. The key point is that all of these technologies come down to the simple fact of monthly, billable costs.
The second point is on network infrastructure, and the trade-off here is population based coverage vs geographical coverage. So in essence, should the cellular and non-cellular network providers offer a good mix of both, then this will improve development across the LPWAN spectrum.
LTE-Cat NB1 (aka NB-IoT) may not storm the current vehicle tracking customers due to limitation on network handover, but will definitely increase in markets outside of this 2G dominated market. From discussions with mobile network operators (MNOs), 2G sunsetting is not currently on the cards until 2025. This may change in the near future with countries like Australia and North America already fully operational on NB-IoT and LTE CAT M1 (aka CM1).
I do believe that once the smaller issues on the cellular networks have been ironed out, this will fast track the local market into this new era of cellular based LPWAN products. Quectel has geared its product offering to allow for ease of migration from a 2G solution to an NB-IoT solution – yes there are small software changes but in comparison to a complete redesign that incorporates a different LPWAN technology, the changeover is possible within 4-6 weeks.
This changeover keeps with three key aspects for end user demands:
1. Firmware over the air (FOTA) updates of the ‘black box’.
2. Data on demand and not limited to data packet size.
3. 2-way communication between backend and field device.
What is the status of the rollout by SA telcos?
Currently Vodacom have ‘opened’ a large number of sites for NB-IoT in Gauteng, but the spread is limited as some areas are densely allocated and others have almost no connectivity.
MTN has been rather quiet, but from my understanding they are ready for both NB-IoT and CM1, however they are looking into business cases and will ‘switch on’ the required LPWAN on a solid case.
NB-IoT SIM cards will be required, but may be limited to customers with genuine applications; this will need to be enquired with the desired MNO.
The billing information and how this will work has not been refined, but it is safe to say that for budgetary purposes it is safe to use the current GPRS data rates.
Quectel has done numerous testing on the NB-IoT networks with both local and international companies. The results have proven successful and our local FAE is geared to support customers using Quectel 2G products, who want to future proof their products.
For what applications should electronics designers consider NB-IoT?
This may be the most controversial question around the NB-IoT space. The 3GPPP specification was updated to allow for NB-IoT handover as this was not possible before. With that being said, it may not suit tracking a high-speed chase and in the vehicle tracking markets is currently not deemed a suitable 2G replacement.
Locally the vehicle tracking market is by far the dominant force when it comes to technology implementation. I believe that some pointers regarding the finished product will offer suitable guidelines for engineers wanting to implement this technology (this is not conclusive, but only a guideline):
1. Fixed installation – where the product will not move at all, i.e., alarm systems, cold storage management, server rooms, etc.
2. Geo-locked installation – the equipment can be moved to various locations for use and operates only within that location, i.e., generator management, containers on hire, etc.
3. Metering – where any form of pre- or post-paid metering is required, with low power and low cost (no external MCU required). The key here is ensuring that the data was actually sent, and if the service needs to be suspended the server advises the field unit and the action is carried out.
4. Renewable energy – with solar, wind and other emerging energy sources and hybrid vehicles requiring charging stations, maintenance and support are key for ensuring uninterrupted supply. This management and decision making can be managed on the unit or from a cloud based platform, allowing the end user a customisable interface.
5. Remote management – this unit will typically gather outside information and pass it to a cloud or backend server. The server can then analyse the data, make a decision and then instruct the field unit to action a specific task. An example here would be a standard gate motor controller that enables monitoring time and attendance of a domestic worker, or allowing a garden service access to a property within a dedicated time on a specific day. Changes are made on the cloud platform and then update the unit as required.
What products does Quectel offer for NB-IoT?
Quectel offers two major lines regarding the NB-IoT space. The base line is simple, 2G to get the proof of concept working with a drop-in replacement NB-IoT. Both modules allow for having the application run on the module, thus eliminating the need for an external MCU, so in essence there are four parts to the design: module, PSU / battery charger and antenna. The peripheral interfaces are I2C, SPI and UART to integrate into CAN bus, sensors, Modbus / RS-485 and so on. This is the M66/BC68 option. The development environment is based on Eclipse and is C programming compliant.
The flagship range offers a wider spectrum allowing for moving from 2G to 3G to NB-IoT, CAT M1 and even as far as LTE CAT 1, with some variants incorporating GNSS (global navigation satellite services) in a single solution. This range is the x91/95/96 series. More in-depth development is required and requires an external CPU.
Are you seeing much adoption of NB-IoT locally?
At the start of 2018, there was much talk on the NB-IoT side but little design activity, however in the third quarter of this year we are seeing greater interest in the base line solution, with a few clients already busy with designs and preparation for production rollout for supply as early as the second quarter of 2019. Some will be for export, but local deployment will depend on the networks’ rollout.