Qualification

While being the perfect technology for a lot of use cases, Sigfox is not adapted to all the needs of customers today. This page will take you through the limitations and possibilities of the technology. 


How to start a Sigfox project ?

At Sigfox, our main objective is to provide our customers with the best network possible. We don't develop or sell end-to-end solutions, but we rely on our ecosystem to deploy them. 

As an IoT project involves different types of companies and skills, you can get help from specialists on every topic you need to focus on.  Please take a look at our partners website to find the best partners for you. 


The right technology?

While Sigfox is a very good technology for numerous projects, some use cases may not be feasible as of today. 

1) Small messages

The Sigfox protocol is designed to be extremely efficient and allow devices running over our network to have many years of battery life. The 12 bytes payload (maximum, but flexible) of a Sigfox message is also perfectly suited for the vast majority of IoT use cases we see today, allowing devices to transmit interesting data to the cloud.

However, this technology is optimized for a specific kind of use case, meaning that some projects requiring high bandwith and constant connection are not really adapted for the Sigfox technology today.

2) Legal limitations 

As the current version of Sigfox uses public radio frequencies (aka ISM bands), we have to comply with the sharing rules in place in the different regions of the world to keep these bands available for everybody.  

In Europe, the ETSI regulation allows devices on this frequency to send messages for 1% of the time per hour. Devices can only send a defined number of message per day to be compliant with the rule, and our commercial contracts were designed to match this limitation.

It is a direct application of the European ETSI regulation : 

  • There are 3600 secs in one hour
  • 1% of 3600 is 36 secs, so a device can emit 36 seconds per hour 
  • A Sigfox messages takes 6 seconds to be sent (for zone 1 devices)
  • So you can  send 36/6 = 6 message / hour  , so  24x6 = 144 messages a day.  ( we keep 4 messages for protocol use)

NB : This rule is just an example of what is done in EMEA region (Europe, Middle east, Africa), depending on location, limitation can be very different.

To get more details on the Sigfox technology, you can download the Technical overview available below.

General technical overview

What can 12 bytes be used for?

Sigfox messages are small and optimised for sensors, as they require only a small amount of power. The Sigfox payload is limited to 12 bytes (excluding the payload headers). Although this might seem a very restricted message payload, there's actually a lot that can be done with 12 bytes.

The example below shows how you could structure 12 bytes to send a set of GPS coordinates along with speed, acquistion time and the battery voltage.

Direct cost

The Sigfox network has been designed and optimised to be very cost-effective for our customers.  From the hardware you need to create a device to the cost of network deployment, all the details have been cautiously taken care of to offer the most optimised IoT solution on the market. 

1) Hardware costs

As the technology is free to implement for semiconductor companies in their solutions, the cost of modules and all the other radio solutions is low in comparison to competing technologies. Starting at less than 2€ for certified modules, you will be able to create connected devices for a relatively small investment. 

As electrical consumption is very low, battery costs are also lowered compared to other solutions, which impacts greatly the overall bill of material costs. 

2) Network costs

The total cost of ownership of your solution also integrates the network subscriptions. Our business model is based on yearly subscriptions paid by customers to connect to our service. 

As the the technology itself is very long range, we have optimized our deployment costs by lowering the number of antennas needed to cover entire areas, impacting directly the price of the solution we offer to our customers. 

Today, the price of the connectivity depends on two major factors : the number of messages you need to send every day, and the number of devices you want to connect. 

You can get subscriptions to our network on buy.sigfox.com or by contacting your local Sigfox operator for prototyping needs. 

Geolocation

Geolocation is one of the most interesting use-case deployed with the Sigfox technology, and can be achieved through a numbers of different methods. Let's look at the 3 most common ones, from the least precise, to the most precise: 

1) Sigfox Location  

The location computation is based on the data from the Sigfox infrastructure, coming from several replicas of the same messages sent by a device and received by different base stations. The method used is not based on flight time or signal Doppler shift, but on the signal strength (RSSI - Received Signal Strength Indicator) using a probability model. 

This method is not made to be very precise, but can ensure a quality of service between 1 & 10km precision, which is already good enough for some tracking use cases. 

Relying on regular Sigfox messages to be calculated, this solution has 2 main advantages  :

  • No additional hardware is required
  • battery consumption is not impacted

It is perfect for high volume solutions which don't need extra precision and where battery life is key. Here is a guide on how to create a geolocation callback on our backend platform.


2) Wi-Fi positionning 

Another common method to find the position of a device is through listening to WiFi networks around it, which will be linked through Sigfox to a WiFi hotspot database, in order to position the asset. 

How does it work? 

  1. The device (equipped with WiFi hardware) "listens" to the different networks around it and recognizes the two strongest ones
  2. The device sends the BSSIDs of the WiFi networks through the Sigfox network (a WiFi BSSID is 6 bytes, so 2 BSSIDs are perfect for a Sigfox message)
  3. Once received on your platform, the BSSIDs are sent to a WiFi hotspot database for matching
  4. The Hotspot database server answers with an approximate position ( 25m to 50m) 


This method has numerous advantages  : 

  • Works indoor
  • Energy consumption is average
  • Extra hardware is not required
  • Precision : 25 to 50m

But also some disadvantages : 

  • WiFi hardware is required
  • Only works if WiFi networks are available
  • Access to the WiFi hotspots database is rarely free 

You can see a quick example of implementation here on Github. 

3) GPS positionning

The most common way of obtaining geolocation is through the GPS method. Adding a GPS module to your hardware, you will know the position of your assets very easily. How does it work ?

  1. The GPS module listens to the satellites in sight 
  2. Once done, the coordonates are sent through the Sigfox network ( A GPS coordinate is usually stored on 6 bytes, so you can send 2 full positions within a Sigfox mesage)
  3. The data are transmitted to your own server and can be localized on a map

GPS has multiple advantages : 

  • Highly precise (up to 15m) 
  • Widely used
  • Works almost everywhere on the planet

But has also his disadvantages ;

  • High battery consumption 
  • Not very efficient indoor
  • Expensive hardware

You can find an example tutorial of Sigfox + GPS here 

You can see all the tracking solutions already available here  on the Partners network. 

4) What is the best for my project ? 

As for modules, it's up to the use case you're targeting. While the Sigfox Network Geolocation might be better  for some use cases needing high battery life, some will prefer the GPS for its precision, or even WiFi for the indoor.  It all depends  what you need to achieve. 

A good solution is sometimes a mix of some of them, and that is why module manufacturers are releasing on the market hardware including the three technologies on board. 

The Sigfox IoT Agency

In order to help our customers reach their objectives faster, we have also created a professional services team called the IoT Agency dedicated to assist companies developing their own solutions.

Our team is specialized in hardware, radio, project management, web applications etc, so if you wish to engage Sigfox to develop your projects, please contact us

Compatibility

Some of the devices  developed for other technologies might  already be compatibe with our network completely out of the box, with just a firmware upgrade. 

If you’re using one of the compatible chipsets for other purposes today(private network, proprietary protocols etc.) it could be possible to reuse the same hardware and be Sigfox compatible, by adding the Sigfox library and upgrading the firmware.  

As the Sigfox network is quite specific, some limitations exist meaning that not all devices will work out of the box. 

The compatible chipsets are : 

  • Texas Instruments: CC1120, CC1125, CC1310, CC1350
  • Silicon Labs : EFR32, EZR32
  • Semtech : SX1272, SX1276

If our team validates compatibiity, you will have to go through a compatibility call with our certification team to validate the use case.

If you would like to know to know if your device is already compatible with the Sigfox technology, please contact us.