As more countries adopt a concept of Smart City the demand for connectivity and IoT technologies is growing. However, the number of devices and options available can be dizzyingly confusing for both system integrators and end users.
We’ve decided to compile a little helpful guide to distinguish between two leading IoT technologies – Sigfox and LoRa.
In essence, both Sigfox and LoRa do the same thing – they give cost efficient connectivity for low-power devices. The quantity of data is not large, so battery powered devices can work from 10 up to 20 years, making the whole system sustainable.
The differences lie in how the data and transmitted and in the business models of networks themselves.
Sigfox uses ultra-narrowband technology, the idea is to take narrow parts of spectrum and encode the data by changing the phase of the radio-wave. The receiver is only tuned for that small slice of signal which helps mitigate noise.
LoRa uses a wider spectrum and uses Chirp Spread Spectrum, the data is encoded in “chirps” - changes of frequency over period of time.
Due to technological differences, Sigfox fares better against the noise, but requires a more complex base station unit as a receiver.
LoRa gets more interference, but it’s transmitter and receiver components use the same radio. That’s why LoRa basestations are less expensive than Sigfox ones.
Both networks have bidirectional functionality, but LoRa is significantly better at at, due to the fact that basestation and end point uses the same functionality. Sigfox’s asymmetrical link means it’s much more powerful from the end point to base station than in the opposite direction. Sigfox also limits messages to 12 bytes.
Both networks use unlicensed frequency bands, that are free for use by anyone. In both cases it’s a good idea to check which frequencies are available for usage in any given country and check noise levels that can be created by other devices and networks.
The business model of Sigfox and LoRa varies significantly and can have implications for a smart city project. Sigfox is a single network – it means that it’s leased for use for individual projects for a fee. So for example for energy monitoring projects, the Sigfox network charge adds to a total charge. A little for every measuring point. Sigfox network also has to be available in your country – as of 2018, some countries like Spain and Italy for example still have very uneven coverage. On the flip side, there will be no network challenges. There can be only one Sigfox network in each area.
LoRa unlike Sigfox, is an open network. So it is possible to build a completely private IoT networks. However, all LoRa semiconductors are manufactured by company that have creates LoRa standard – Semtech Corporation, that means that there is much less variety when it comes to modules and gateways, as all of the key hardware is coming from the same company.
Overall, Sigfox is probably a better option for purely monitoring, data aggregating solutions. For things like Co2,Humidity or temperature measurements, parking sensors and similar applications it would be better(if it’s available ofcourse). Sigfox also capable to identify and authenticate device which gives additional security benefit.
LoRa is better options for solutions that rely on communication in both directions, like command and control, smart grid etc. It is also better suited for applications that are sensitive about their data and networks, like utility. LoRa allows to create a network which entire operation and control is private. It is also more flexible for international solutions where some countries involved simply have no Sigfox coverage.
There is little doubt that each IoT network brings it’s own benefits. However, it’s not always obvious which is the most cost efficient. Some device type vary in price, both ways and many hardware pieces, can actually be customized to work with both.
At this point, there is no clear answer if any single network will become defacto standard for Smart city applications.
If you have a question about Smart Cities, or want to share your expertise – let us know at info@enectiva.com