This last monday I had the chance to meet the two Sigfox founders Ludovic Le-Moan and Christophe Fourtet during a really nice day at Labege (SigFox headquarter) with other Sigfox ambassadors.

From the meeting we had with the founders I retained some of the Sigfox strategical guide line:

• Scalability –  this is the major point raised during our discussions : the network must be able to scale and all what has been designed in the radio protocol & technology, as in the cloud architecture was for scalability.

Thanks to this initial design no big change are expected in the radio solution in the coming years. It has already been designed for future.

In regard to this scalability strategy we have also meet the team operating the network. I’ve seen a really nice Network Operation Center, well equiped and with about 40 people involved. It has been fun for me as in my daily job I’m managing internal inter-application communication of a large company. The volume of data we are proceeding every day is quite similar as of now but Sigfox is well more equiped than I am and better prepared for scaling 😉

• Reliability – The ISM band will continue to have more and more noise on it coming from all the coming radio device using it. Sigfox design has been made to ensure a long term capacity to support this evolution. Ultra narrow band is actually the best and secure way to continue to communicate over noisy environment also protecting this common good by limiting the spectral usage.

• Simplicity –  Sigfox has been made to be simple to use with no parameters to tune the radio or the protocol. Everything is defined to ensure a good quality in the communications. This spirit will be kept in the future but potentially we will have the capability to tweak some of the parameters. We could imagine to limit the repetition time for frame with lower criticality. This will save power or send more frame per hour. We could imagine to get higher speed. Why not having more downlink ? Larger payload ?

A lot of candidates for future evolution of the network has been presented to us; Even if I can enter in the details of what has been presented, some feature are really interesting.

• A network broadcast and multicast downlink communication could arrive soon, it is not a surprise as it has been discussed for long time but this time it sounds to be in a really near future. This capability will give alow the devices to receive a time synchronization signal ; to discover the zone it is covered by ; select the right ISM band for its future communications… Custom payload could be transferred that way also to activate/configure a group of devices.

• Collaborative gateway is another really expected feature for mobility : this is a purely operator application having large impact on devices. Actually when an object is moving the risk of loosing frame is large. Actually every gateway receiving the signal is validating the CRC of the frame before reporting it. As a consequence a lot of frame are dropped when, in fact, if we merged the signal coming from all the gateway we could get a valid frame. This is the purpose of the collaborative gateway : use a backend processing to rebuild the signal received by multiple antennas to get a correct frame from a mix of incorrect received frame.

• Network density and growth : new gateway has been announced, they are really smaller and easier to deploy. Operator have no need to host the gateway in a telecom center : it can be directly deployed outdoor and connected to satellite, 4G, ethernet, DSL … This is simplifying deployment and reducing cost. The gateway can also be solar powered with a 2 meter square solar panel. This configuration allows to deploy the network everywhere, quickly and at low costs. I assume it’s a game changer for deployments like in Africa but not only.

Even with a dense network it will be really hard to cover 100% of territory like in isolated valley and also in big building of underground parking… Solution are also coming to solve it.

• The Sigfox repeater will be soon on the market with a really accessible price. The solution will be “open hardware” (not fully open but you can build your own based on schematics and given libraries). It will allow to repeat a  Sigfox communication from indoor to outdoor. The device (I’ve seen it) is really small and fully autonomous with a 5 year battery you can change. It can repeat any device messages (in respect of duty cycle) or repeat given devices. Device is IP67 and listen to Sigfox device about 400m around. Price will be really accessible : some tens of euros.

Sigfox network will also be able to be extended more easily with different smaller devices customer will be able to deploy. Actually you have a “mini base-station” you can deploy in your building / factory … for getting a better signal or a better redundancy  for your devices. Compared to a repeater a network extension allow to get benefit of a full duty-cycle per device and scale with a larger number of devices. This offer will be redesigned for a set of two different solutions:

• The “new mini base-station” will achieve a lower cost (hundreds of euros) with a capacity of 50 simultaneous messages. It will be perfect to cover building, parking, facilities, farms…

• The “local access point”  designed to be a really low cost device, very small, totally plug&play to accompany B2C devices and cover a home or an office.

With network densification and locally deployed gateway it opens large capabilities for make objects with longer life on battery. By reducing the distance we can optimize communication budget link : we can transmit lower than the 14dB. Actually we can already, manage device power dynamically when the signal is quite good, stable and the object not moving. This feature could be later be implemented by the network to reduce the development time of a such feature by every device makers.

Reduction of energy consumption enable more and more harvesting possibilities. We had in Sigfox demonstration of Sigfox emission with Pelletier effect, we can imagine device powered by body movement, temperature of monitored devices … the use cases are large and the interest of removing batteries is important to make connected object at object life duration.