Subject: [lp-wan] Sigfox coverage precisions

From: James Newton <[email-masked]>
Date: Tue, 1 Nov 2016 21:52:20 +0100

Hi all.

I need to make clear I'm not in any way a radio engineer, but from working
on wireless projects over the years, have acquired some understanding of
radio transmission concepts.

The official coverage maps used as the basis in contractual agreements with
Sigfox can be found at http://www.sigfox.com/coverage

The number of gateways (or base stations as they like to call them) per
given area depends greatly on land topography and urban density. A hilly or
built up area requires more base stations than on flat open land.

Sigfox's CSO and confounder, Christophe Fourtet, has always declared that a
standard Sigfox gateway is able to manage up to 1 million devices per day,
each being able to transmit up to 140 12-byte messages per day (so a total
of 140 million messages per gateway per day or 1620 messages per second)

Coverage figures are given as a percentage of the population, this is
understandable as 100% coverage of an area is technically almost impossible
to guarantee. Indoor coverage measurement requires on-site testing as
penetration depends on the material and density of the building (metal
reinforcement, thermal film in glass windows, etc.)

For Sigfox, in France and Spain, the declared coverage is around 90-95% of
the population for outdoor applications.
Portugal, Ireland, Luxembourg, Belgium and the Netherlands are well on the
way. No other countries have over 50% of their population covered at the
moment to my knowledge.

People at Actility and Objenious who deploy LoRaWAN networks state that
LoRa has better indoor penetration. Apart from the fact that LoRa gateway
deployments require higher density (more gateways) per given area then
Sigfox, I'm not sure how this stands up to reality as legislation implies
same output power limits for devices using ISM bands.

Sigfox patents cover the way their gateways detect a specific energy
footprint before syntonising. In their transmission protocol, one message
transmission implies that the device transmits three times the same data
frames on different frequencies (ultra narrowband frequency hopping).
Hence, the gateway cannot know exactly on which frequency the device is
transmitting. This explains why Sigfox gateway deployments are less dense
than those done using LoRa technology.

I hope this insight helps.

James Newton

---

From: Jiazi Yi <[email-masked]>
Date: Wed, 2 Nov 2016 09:58:43 +0100

Dear James, 

The coverage is, of course, an important factor. But normally, more information is needed to have correct interpretation of it, such as number of active devices. Why it’s important? For example, if I set up a shortwave radio broadcast station, I can declare that my service has global coverage — but it’s possible that there is no single people listening on it. 
Of course, Sigfox probably chooses not disclosing detailed information at this point, which is totally understandable. 

In the coverage map that you provided (http://www.sigfox.com/coverage <http://www.sigfox.com/coverage>), I don’t know how it’s generated in the center — but at the edges, I have the impression that it’s a set of R=100km circles? 

Caveat: as one from academia, I have neither Sigfix nor LoRa box to sell ;) We ask nasty questions just because we are used to do it to our colleagues and students, and have great curiosity on LPWAN-related technologies. 

best

Jiazi 
Ecole Polytechnique, France

> On 1 Nov 2016, at 21:52, James Newton <[email-masked]> wrote:
> 
> Hi all.
> 
> I need to make clear I'm not in any way a radio engineer, but from working on wireless projects over the years, have acquired some understanding of radio transmission concepts.
> 
> The official coverage maps used as the basis in contractual agreements with Sigfox can be found at http://www.sigfox.com/coverage <http://www.sigfox.com/coverage>
> The number of gateways (or base stations as they like to call them) per given area depends greatly on land topography and urban density. A hilly or built up area requires more base stations than on flat open land.
> 
> Sigfox's CSO and confounder, Christophe Fourtet, has always declared that a standard Sigfox gateway is able to manage up to 1 million devices per day, each being able to transmit up to 140 12-byte messages per day (so a total of 140 million messages per gateway per day or 1620 messages per second)
> 
> Coverage figures are given as a percentage of the population, this is understandable as 100% coverage of an area is technically almost impossible to guarantee. Indoor coverage measurement requires on-site testing as penetration depends on the material and density of the building (metal reinforcement, thermal film in glass windows, etc.)
> 
> For Sigfox, in France and Spain, the declared coverage is around 90-95% of the population for outdoor applications.
> Portugal, Ireland, Luxembourg, Belgium and the Netherlands are well on the way. No other countries have over 50% of their population covered at the moment to my knowledge.
> 
> People at Actility and Objenious who deploy LoRaWAN networks state that LoRa has better indoor penetration. Apart from the fact that LoRa gateway deployments require higher density (more gateways) per given area then Sigfox, I'm not sure how this stands up to reality as legislation implies same output power limits for devices using ISM bands.
> 
> Sigfox patents cover the way their gateways detect a specific energy footprint before syntonising. In their transmission protocol, one message transmission implies that the device transmits three times the same data frames on different frequencies (ultra narrowband frequency hopping). Hence, the gateway cannot know exactly on which frequency the device is transmitting. This explains why Sigfox gateway deployments are less dense than those done using LoRa technology.
> 
> _______________________________________________
> lp-wan mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/lp-wan

---

From: James Newton <[email-masked]>
Date: Wed, 2 Nov 2016 11:23:55 +0100

I can reassure you in saying that I see nothing nasty in your questioning,
Jiazi :-)

While I used to work for Sigfox and have been working on M2M and IoT
solutions for almost 20 years, I am now a freelance business developer and
consultant for IoT and M2M solution providers.

This, of course, implies neutrality and an agnostic approach to all IoT,
LPWAN technologies. Hence my presence on this mailing list.

I think we need to be realistic here. There are, at this time, very few
active devices in the field transmitting data to the LPWAN operators'
servers.

What was disruptive with Sigfox was less the technology (an assembly of
technologies dating back to WW1 submarines, that's 100 years!) than the
guts to put an end to a chicken and egg situation and deploy the first
nationwide LPWAN for IoT devices while the latter where not actually made,
let alone deployed.

Hence, the Sigfox network, as is also the case of LoRaWAN these days, is
hugely under exploited. The plumbing is there, but the pipes feel dry. My
wet finger estimate is that less than 3 million devices currently send data
over operated public LPWAN networks worldwide. And most of these will be
sending an average of one to two messages per day. Nothing to get excited
about.

The big deals to feed these networks just haven't been signed yet. And even
those that have imply ramp-ups to a million or a few hundred thousand
devices over several years. So very few in the first stages which we are in
now.

However, the deals are coming and difficult beginnings are not an omen to a
bleak future. It just takes time for companies to get their heads around
these new technologies and make decisions to invest in their use.

This is why, parallel to the race forward in network deployment, operators
are focusing on developing ecosystems of hardware manufacturers and
software developers to make IoT adoption as easy as possible.

Furthermore, deployments and activation of end devices (mostly GPS
trackers, home security and smoke alarms at this time) are at the
discretion of the user (when you buy a connected smoke detector for your
home, the vendor doesn't know where you live). It's very difficult to draw
up a map of where devices are. While the operator knows which gateways are
most sollicited by connected devices, it's not information they are ready
to provide as it would reveal the extent of network dormancy.

Sigfox coverage maps are based on algorithms that take into account
landscape and obstruction from buildings. A base station set on hill side
will entail a display of coverage that is very lop-sided. The hill masking
a whole portion. This information is ground proofed by testing in the
field. If you have a Sigfox-enabled class 0 device, you'll find the maps
are pretty reliable.

You are therefore right, LPWAN coverage with huge potential is there but
with very few people using it right now.

James Newton

Le 2 nov. 2016 9:58 AM, "Jiazi Yi" <[email-masked]> a écrit :

> Dear James,
>
> The coverage is, of course, an important factor. But normally, more
> information is needed to have correct interpretation of it, such as number
> of active devices. Why it’s important? For example, if I set up a shortwave
> radio broadcast station, I can declare that my service has global coverage
> — but it’s possible that there is no single people listening on it.
> Of course, Sigfox probably chooses not disclosing detailed information at
> this point, which is totally understandable.
>
> In the coverage map that you provided (http://www.sigfox.com/coverage), I
> don’t know how it’s generated in the center — but at the edges, I have the
> impression that it’s a set of R=100km circles?
>
> Caveat: as one from academia, I have neither Sigfix nor LoRa box to sell
> ;) We ask nasty questions just because we are used to do it to our
> colleagues and students, and have great curiosity on LPWAN-related
> technologies.
>
> best
>
> Jiazi
> The official coverage maps used as the basis in contractual agreements
> with Sigfox can be found at http://www.sigfox.com/coverage
>
> Sigfox's CSO and confounder, Christophe Fourtet, has always declared that
> a standard Sigfox gateway is able to manage up to 1 million devices per
> day, each being able to transmit up to 140 12-byte messages per day (so a
> total of 140 million messages per gateway per day or 1620 messages per
> second)
>