15 characters of LoRaWAN?

Interesting low power, license-free radio tech suitable for a property-area or even much longer (article cites 10km - which is basically LOS) ranges.

Not sure what could be made of this, but a bonjour-based self-meshing comms network might be useful. Seems fairly robust to interference too.

Anybody toyed with this before?

@Canem uses this for some of his property network stuff - I expect he’ll have some insights!

I call it DEWS: driveway early warning system [a devlog] is LoRa based.

I got interested in LoRa because both point-to-point, mesh, and LoRaWAN stuff is very similar to APRS and some of its capabilities. I think LoRa is really cool in it’s up-and-coming state since no license is required. I think there are/will-be many more projects around to gather inspiration from folks who arn’t hams.

Not to mention the kilometers-per-watt is significantly higher. My comparison experiments have been pretty minimal and not at all rigorous, but the max output from a lora module is 20Dbm, or 0.1 watts. Similar performance near 144mhz APRS took .5 to 1 watt. So that opens up lots of possibilities with battery powered projects.

IIRC it claims down to -115Dbm sensitivity. I’ve tried it from about 100 meters away from the metal-sided shop building, and was still receiving at about -90Dbm. About -70Dbm if I opened the door.

LOS data on 1/10th a watt or less? Yes please!

LoRaWAN specifically I haven’t played with. I think you’d call that the complete network layer? it’s the standard for routing packets both in mesh configurations and the Lora/Internet bridges that exist in various forms. LoRa receivers moving data from the radio to a cloud server via MQTT, is one common example.

Like this: https://www.thethingsnetwork.org/

Personally (angst about cloud services aside) it’s more overhead than I’ve needed for my projects. I just talk to the radios directly, and handle packet creation/reception myself. Mostly it’s been arduino to arduino talking, but I also have one ‘gateway’ built to allow me to interface with the property-area-network stuff from any PC/phone in the house as well.

It’s in this picture, that I haven’t done a write up of yet. Above the light is a camera enclosure, into which I have stuffed a POE splitter, raspberry pi3, custom LoRa board, and noir camera.

Then with this project: RPi-Cam-Web-Interface - eLinux.org, I have buttons placed on the camera-viewing page that lets me open the gate, switch the lights, and so on. Receive button clicks on webpage, send commands out via LoRa.

I could go on! I’ve got several more half-done Lora projects around, and several more ideas for the future when I get those first ones done.

A $5 data radio the size of a postage stamp? This is the kind of technology I can get excited about!

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I should get some of those to mess with. Just haven’t felt like screwing with microcontrollers lately.

I may do a driveway traffic detection system with ultrasonics - we can compare long term behavior!

Has anybody here heard of the gotenna mesh? goTenna Mesh | Buy Now

It’s a cool idea that started appearing in the HAM magazines a couple years ago. i was never able to find out what exactly the hardware inside is, but I’ve been thinking what a cool project it would be to try and build one with Lora and an esp32. Basically a tower-free short-range text-message network.

Using the esp32’s bluetooth means a smartphone could be the display and keyboard. Although since I know nothing about app development maybe it’s easier to make a full standalone terminal with tiny keyboard and display. Hmm… projects to dream about.

Update: I’m not the first to have this idea. yay!

Ok, time to go into my mantra: “No starting new projects until you finish the current ones… No starting new projects until you finish the current ones…”

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If you go this route, one of the main issues is seeding enough boxes. May I suggest some small solar/battery/antenna boxes that look Very Official Indeed that can be attached to random power poles and buildings and hopefully stick around?

Ohh, I like that idea. I was thinking just devices carried by friends/groups and would work when they’re in range of each other, but that has me thinking.

Something like a big decal on the front:
Geological Survey Equipment. Please do not remove.

That, or stuff it into an old outdoor wireless access point enclosure. Nobody wants to interfere with the wi-fi :wink:

I’ve been playing with the concept of wifi “standalone archive” systems for a while - think a local Wikipedia mirror, Gutenberg mirror, and some other helpful stuff along with a file drop zone.

May as well add mesh networking to them! :slight_smile:

Hmm, I like it. 2.4ghz/wifi data transfer with a UHF control link? Raspi Zero-W or maybe an ESP8266 for lower power consumption. There’s a lot of possibilities in that project.

I was thinking something in the line of a RasPi or RasPiZero, with appropriate stuff hung off it. The Zero would require a lot more external hardware than the Pi, which can be an AP with built in wifi, and has some full sized USB ports for bigger-antenna APs (I was thinking of an external antenna).

My tentative plan was to go with a SD card for the read only data (run the OS read only, main archive data is read only), and a F2FS filesystem on a USB drive for the read-write storage. That way, it’s less likely to zap the main SD card with write traffic - and random power cuts aren’t a big deal, data-integrity-wise. Toss an Arduino on to control power to the main system, use a low temperature tolerant chemistry (or simply refuse to charge if cold), and you’d have a year round data store.