So, I’ve got some LoRa click boards. What should I do with them? Obviously, it will be something that connects to the Internet, so the first thing I need is a LoRa Gateway.
Now, I have two choices: either I buy one (but it’s quite expensive), or I make one from scratch. I will choose the latter option, both for cost-related reasons, and because there’s much to learn by trying to build myself one LoRa gateway.
LoRa gateway; the hardware
As in many of my projects, it happens that I already have all I need: one Raspberry PI1 Model B that was gathering dust in my junk box, plus one PI click shield. I also have one Raspberry Pi2 Model B, and its corresponding PI 2 click shield. I will use one LoRa click board from MikroElektroniks, on which I placed two antennas.
The first version of my gateway is built using the PI 1 model B and it looks like this:
Piece of cake. Just plug the PI shield, place the LoRa click into the mikroBUS socket and that’s it. The Raspberry PI model 1 doesn’t pack a lot of processing power, but that’s no problem: the gateway doesn’t have to process a lot of data, so it will work fine.
However, on the hardware side there are several issues. First the Raspberry PI 1 model B doesn’t have mounting holes, so it’s hard to put it into a permanent enclosure. Second, the micro-USB connector used to power the board is on the same side with the antennas, so again it makes mounting into an enclosure quite complicated. The third issue is that the metal spacer that comes with the PI click shield touches the components on the Raspberry Pi – in the pictures above I had replaced it with a black plastic spacer.
Switching to the newer Raspberry PI 2 model B:
The first nice thing is that Raspberry PI 2 Model B has mounting holes, so I can easily fix it into an enclosure. Second, the antennas are placed on the longer side of the Raspberry PI and there’s nothing around the antenna connectors. As such, mounting in an enclosure becomes a child’s play. All I need is two holes on the side of the enclosure so the connectors come out. Ethernet and micro-USB power connectors are also accessible. I’m already thinking on a bigger box, so I can also place also a 5V PoE splitter/adapter inside.
LoRa gateway: the software
Fortunately, one does not need to write the gateway software from s=scratch: there are already some good gateway implementations.
The software developed by C. Pham (LIUPPA laboratory, University of Pau, France) can be downloaded from http://cpham.perso.univ-pau.fr/LORA/RPIgateway.html. It also comes with an Arduino example for a LoRa node, so it’s basically all you need to start a simple network in almost no-time.
Another gateway is developed by the Pi in the Sky project. This one supports two LoRa modules, so you can populate also the second mikroBUS socket of the PI2 shield.
This post from rs-online.com describes another approach to building a LoRa gateway. It uses an iC880A, so you might need to do some minor code changes.
In this post from disk91.com the same RN2483 module as in LoRa click is used.
Bash utilities to use RN2483 microchip LORA from Raspberry pi (RPi) are available on GitHub.
A RN2483 based, LoRa enabled laptop.
Cooking-hacks.com provides some nice LoRa tutorials.
Yet another Implementation of a Lora gateway with a cost under 200 EURO can be found at https://github.com/mirakonta/lora_gateway/wiki.
Finally, you might wish to check
http://openlora.com/forum/. Many answers to common problems can be found there.
These are just some examples of LoRA gateways, but there may be other implementations too. So, if you know about some other implementations I’d be happy if you will share that information.
[Update April 4, 2017] There’s a nice, cheap LoRa gateway from Dragino. With a price of 61USD (VAT, customs taxes and shipping costs not included), the LG01-S goes right on top of the cheap LoRa gateway list.