What about other technologies? With ZigBee networks, you’re not meeting many IOT application requirements, and low power Wi-Fi is still in design. A new class of technology has emerged lately, which is now generally referred to as the low power wide area networks. These networks enjoy the following advantages– first, large coverage. Due to some technical magic, which I’ll explain in a moment, these networks offer suburban and rural communication ranges of more than 20 kilometres. Typical urban ranges are five kilometres, and difficult urban ranges of one to two kilometres.
The latter occurs, for instance, in the case of smart parking, where a metal object is blocking the communication’s path, or in the case of smart metering, where the meter might be in the basement. Second, low cost. Given that involved patent, development, and hardware costs are low, the entire radio chip solution is typically a fairly low cost. The same holds for the subscription fee, in the case of an operator model. The ballpark figure today is about $1 per chip, and $1 per year, per subscription. Third, availability. In contrast to other technology, this technology’s available today, and therefore of great use to emerging IOT deployments.
It works successfully for very large projects, like the Moscow Smart City deployment, where almost 20,000 sensors are connected to some very few access points. There are more and more technology players emerging in this field, with the pioneers being Sigfox, Cycleo, On-Ramp, and Newell. Sigfox, a French company, operates in the sub-gigahertz band, using ultranarrow band radios, which due to most noise being cut out because of the ultranarrow bandwidth, enjoys massive signal power advantages, and is thus operational over very long distances. A message takes a few seconds to be transmitted, but collisions, even with a large amount of endpoints, are rare, due to the specific proprietary wireless access control used, and there really a lot of channels being available.
The business model resembles the one of an operator. That is, Sigfox instals and operates the network, and ensures wireless connectivity. Cycleo, also a French company, and recently acquired by chip giant Semtech, also operates in the sub-gigahertz band. It essentially uses spreading spectrum techniques, with very, very long spreading sequences. The large spreading gains yield the needed link budget, and also a very large range. The business model here encompasses only the provisioning of the equipment– that is, there is no operator model. On-Ramp, a US company, operates in a 2 to 4 gigahertz ISM band, and uses a propriety wireless access control. The solution offers a very large link budget, and has excellent range.
They are very active in the oil and gas business, providing real time instrumentation of breaks, wells, and pipelines. Newell, a UK company and recently acquired by Chinese telco giant Huawei, focused initially on TV white space spectrum, but recently shifted to other bands, too. Notably, Newell is exploring the idea to pack with a cell operator, and offer service level agreements of a licenced band. This is a very attractive notion, indeed, for companies which do not want to deal with the problems arising with wireless connectivity. Some of that technology may actually end up in the cellular standardisation body of 3GPP, since it has now the backing of some vendors and operators.
On the downside, all these technologies I mentioned here are still proprietary, but first standardisation efforts are being undertaken by ETSI and the IEEE. Also, alliances start to appear, such as the Weightless special interest group for Newell, or the LoRa Alliance for Semtech.