There are multiple ways to track something or someone. Cellphone are using different method to be able to give you a precise location in most of the situation. The more global one is GPS, it works anywhere on earth but do not really work indoor. It is also costly (about 8$ or more) and power consuming. Outdoor your usually have a precision of 15 meters. The less precise one is triangulation : a message received by different antennas will be located by the network in an area covered by all these antennas. This solution works anywhere the network is covering and do not need specific power other than for communicating. The precision is usually from 500m to 10km.
The last usual method we use is the one we are going to implement in this post : the WiFi positioning. The tracker is listening for the WiFi access point around and ask one of the existing database knowing most of the WiFi location to get a position. This is working thanks to the crowding effort all of us are doing with our smartphone of capturing WiFi around us and associated locations. The WiFi solution is working where WiFi is, so usually in the cities ; around buildings. It works well indoor, better than outdoor where WiFi is less active. The precision is about 30-50 meters. The power consumption is lower than GPS.
Sigfox is a LPWA (Low Power Wide Area) network covering about 45 countries (as today) dedicated to low power autonomous devices aka IoT. Asset tracking is one of the best use-case.
The use of Sigfox with a WiFi tracker is allowing to create a low-cost tracker device, autonomous on battery from month to years, getting benefit in 45 countries of a WiFi + network localization.
This post will explain how to get started in this technology by using two standard, easy to use and low cost components allowing to get your prototype for about $5 of hardware.
Sigfox is a really nice technology when you want to make a really quick experimentation in IoT. The Time To Hello World will take you less than 5 minutes and it makes it really easy.
That said after the POC comes the production, and the way you manage your Sigfox backend for production is not the way you build your quick & dirty front-end platform for the POC.
This post will introduce how to make your Production platform and what is the difficulty you need to consider. I’ll propose you some architectural solution I’ve put in place but they are one of the ways to implement it. I won’t detail the pre-packages PaaS solution as i’m not a big fan of them : in my point of view, they are firstly responding to the POC situation, but it is only my own opinion.
Sigfox just released publicly its Radio Signal Analyzer tool. This is a tool for the device & module maker to prepare the P1 certification : basically it checks the radio signal shape, power… and tell you if you are following the requirements.
The tool have to be used with the SIGFOX SDR dongle provided with the SNEK tool.
The software solution can be downloaded here : https://support.sigfox.com/downloads/sigfoxradiosignalanalyzer.iso
Sigfox is a LPWA network using the free radio frequency to communicate. There radio frequencies are changing in the different zone (Europe, America, Asia…) When you are developing a device you need to test it but you are not authorized to use all these frequency from the country you are.
The Sigfox emulator is a solution for this : it allows to directly connect your device and analyze the transmission whatever the frequency you are using is. The Sigfox emulator kit is an SDR dongle with a Sigfox software for understanding, decoding the sigfox signals.
You can wire your transmitter to this receiver to not emit the signal over-the-air and legally use a non authorized frequency in your country. When you are using an authorized frequency you can simply communicate over the air.
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 ?
New comer in the Sigfox ecosystem : the Wisol FM20R1.
Wisol have already changed the Sigfox module world by providing a solution based on the OnSemi design for transmitting on Sigfox network for about 2$. Now they are back with a full SoC solution for a really competitive price estimated under 15$. This solution is providing SigFox, GPS, Wifi, NFC, RF and includes an accelerometer.
In many occasion some of my Sigfox prototypes has been in movement with difficulties to emit ; many source can cause this but basically from discussions with specialists speed is not a close friend of Sigfox technology.
As a quick test is always better than a long theorical discussion, tonight, I took my car and made some tests.
This post details the test of Sigfox running in a car at different speed.