Episode 3 & 4 of my Youtube series about LPWAN is about antennas for LPWAN and impact on object design. The episode 4 go deeper on the way to improve radio performance by tuning and adapting antennas with matching circuit.
As usual, this series of post are summarizing in English the content of my French video on youtube.
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.
This post is a VLOG entry, as usual in French, you will find the english text version in the next part of the post.
Basically, I’m explaining how the two LPWAN technologies : Sigfox and LoRa use the radio frequency to communicate with a low power consumption in a wide area environment.
In this video you will find a mix of demonstration with voice to highlight how it works with day-to-day life example and spectrum capture of both technology to visualize how it looks like.
Since a long to time I did not post about MQTT … The main reason was I uses MQTT as a protocol to publish data directly from a device but in a centralized environment like SigFox / LoraWan you can’t use it directly on the device. Actually I have some devices communicating with a backend and the question about how to provide these information to the customers of my service are raising. To match this pattern I have to ways : providing and API where the information are pulled by the customer and MQTT where the information are pushed to the customer.
One choice is not against the other one, I had the two kind of customers. For this reason I will describe how we can implement a MQTT server (mosquitto) to push Sigfox data device as json content.
I make a post on measuring temperature with different sensors and an objective : watch the impact of designing a correct box for you IoT you want to put in a Car.
When sun is lighting your windshield it is not a surprise to get high temperature, but did you expect to get up to 90°C when the outside temperature is about 35°C ?
The packaging have a big impact on temperature as this post will detail it.
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.
Once you have found the great idea of the year and you want to start implementing your first prototype it is time to choose the right technology. Some would say you should not choose at this step and implement both at end but in my point of view it looks like and economical mistake to do this way. Prototype is to demonstrate and final product. It can request another technology, for sure. But in my point of view the best is to take the right one at the beginning. For most LoRa and Sigfox are both equivalent or for some others one is over the other one, best depends who you ask. In my point of view, if I consider my 2-3 years sigfox experience and my starting experience on LoRa with 1 year background research on it, there is no magic answer. Context of your idea is the keypoint then you have some technical elements to take into account to finalize your decision.
This post will try to illustrate where each of the technology is the best and give you some decision keypoints.
LoRa GPS Tracker
Todays work was to make a simple GPS tracker communicating over LoRaWAN to check the coverage of my LoRaWan gateway in the city. Basically this tracker reports a position per minute to the network. If coverage is good, position will be recorded in the backend. That’s all !
This post details how to do it easily with the low cost and common components : Arduino for the master, Microchip RN2483 for LoRaWan communication and L80 for GPS positioning.