The RF 868MHz is a public bandwidth European Low Power Networks (LPWAN) as Sigfox and LoRaWan are using for communicating.
This bandwidth is regulated by different norms like ERC-REC-70-3E in Europe and have national norms in relation. In France ARCEP 2014-1263 seems to be the last one validated in the JO on the 30th of January 2015. The following video is a second episode of my VLOG on LPWan technologies. As usual, the video is in French but this post will give you a overview in english.
Getting this picture from the social networks it was an opportunity on reacting about the general use of wifi technology for IoT smart home equipment and the risk you have to design a such solution.
The following video is a VLOG about this question. As it is in french, this post will details the main lines about my feeling.
I’m actually doing some experiment with the French LoraWan network operated by Objenious. To receive the message on your backend application, one of the way is to build a callback function to proceed the data.
Due to LoraWan protocol, you have different type of possible callback like for: joining network, uplink messages and downlink report.
This post gives an exemple on how to implement an uplink message callback handler, with php, for your application backend server.
Today Sigfox is releasing a really good document about antenna design. This pretty document can be found following this link (available on July 7th). This document from TI also contains really well detailed information about the alchemy of antennas and the different kind of product you can find. From Silicon Labs you also have an interesting development kit for 868 antennas with performance published in this application note.
This is to say antenna is one of the most important part of a 868 object, as for Sigfox as for LoRa where the problem is basically the same. I discussed with different sigfox object designed and every-time the antenna was a big project issue. Some has payed about 10-15k€ to get a custom optimized design.
I never experiment a custom design but I made test with various antennas and the purpose of this post will be to give you my feedback on the different solutions.
After making LoRaWan test in a city environment, I make some test in a rural environment with the objective of evaluating the capability for being used in connected farming environment.
The result is really like what we have got in a city, eventually better in a way as the antenna position was on altitude. The following map makes with 6kbps communication shows the coverage. You can see that the coverage is really limited on the Eastern direction. This is due to higher mountains this way. Mountain are the main limiting elements and as you can see, even on short distance communication they are blocking any signal.
Read more to access the map.
Last week, Objenious (a bouygues Telecom company) has announced the availability of its LoRaWAN network in France. With already 32 cities covered, about 50% of people can access to the low power network. More over they have announced the deployment of 4000 antennas by end of the year to cover the whole country.
I had the opportunity to test the network and as far as now, I can say it works well, the backend is nice even if it sounds a bit not intuitive yet but for sure they will fix it soon. The good news was a communication about price, with a range of 12€ to 1€ depending on volume, the pricing is really near Sigfox one in a first look. The volume scale will be really important to see the difference as the technical offer (message limit, bandwidth, downlink limit if we have some or not).
In my point of view, Orange is the one loosing most with this announce as they are supposed to start soon with 11 cities in France and they did not yet communicate on the scaling. So now, we are waiting for Orange response and offer in this competition.
The surprising thing in the Objenious announced was the roaming capability with USA as the LoRa frequencies are not compatible between Europe and USA. As most of the device are not yet dual band and the question of detecting the location before emitting still an issue for such use-case, I do not really see how it can have a short term positive impact on project. By-the-way, I was also not aware the LoRaWAN specification for roaming was published. Is it ?
So welcome to Objenious in LPWAN french market, competition is always a good think, and what you announced sounds good and useful for object maker like me.
Microchip RN2483 Lora
Making downlink working correctly with RN2483 on LoRaWan is not a simple a quick thing to do if you do not have all the keys to do it. After spending some time to fix my code for this, here are the tips to consider and not forget !
I was looking for a real LoRaWan experimentation on the field, not only a given open field performance where the result do not match the reality.
For this reason, I installed a Kerlink gateway on a friend’s balcony living on a high part of my city. Then I moved a tracker reporting its GPS position on regular basis and day after day I built a map of the area covered by this antenna.
This post details the results of this expermientation