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Locked Mesh Networking local communications

 

The topic of this essay is Meshtastic, an open source suite of programs designed to communicate using LoRa as the modulation type and mesh as the methodology.
Although it not Ham radio directly, it's components use Amateur shared frequencies within the ISM bands (433 & 915 MHz), making it open to all.

Ben W0AYE turned me on to this facet of the hobby at our last meeting with a couple of Blackberry like communicators that we texted back and forth with.
While this was using the technology at it's simplest form - simplex communication, adding one or more Meshtastic devices(s) creates a basic mesh network.
The is because unless explicitly told not to, all LoRa Meshtastic devices relay all packets up to 3 "hops" to all of the other users on the channel.

To that end, I purchased the $35 WisBlock basic hardware combination for LoRa and solar charging.
It's inside a weather tight enclosure with an external N connector jack for the Lora 915 MHz antenna and a weather tight power cable from the solar panel.
I now have a Meshtastic remote relay mounted up on my tower acting like a digital repeater.
The first thing I noticed is I have a "neighbor" using meshtastic to report weather. I'm still trying to figure out who Sunset Hillbilly is...
Reading below may explain why...
My other LoRa radio is called a T-Deck and it looks like a Blackberry from 20 yrs ago (same as Ben had to the meeting).
In a short drive test today it sent and acknowledged all four transmits which were simply text of where I was when it was sent.
I started at about a mile then 2 then 3.?
Today I tried sending a message from a town hall 4 miles distant and it was in the log when I got home. Yea!

The real point to this post is to gauge if there is interest to discuss this mode further and perhaps, provide a place for us share what we know.
At this point, almost anyone into Meshtastic knows more than I, so the stupid question doesn't exist.

73,
???????Mike N0QBH
 

Meshtastic continued -
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In my previous post I briefly described Meshtastic LoRa RF networking and some of the hardware involved.
Now that I've had my outdoor node online for a month, I know a little more about what is going on around me.
The neighbor with a weather station updating every minute is a constant and I've had no other contact with them and there is no location given.
Occasionally, an active station will pass through on the highway and show up on the open channel (Channel 0) stations list.?
More "exciting" is when an active node in an airplane comes in range. Then the channel 0 station list will show several Meshtastic stations from all over.
This happens when the station in the air hears the stations below and dutifully re-transmits their payload.
You can set your location in the configuration, and if you choose, broadcast it. Then the receiving stations will also plot your location on a map.
Some mesh devices have a GPS built in and (if enabled) can be tracked.?
However, I've yet to have a LoRa text qso with any of them because I wasn't active when they were going by. Kind of typical for radio :)
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MQTT
Connecting mesh users out of LoRa (radio) range via the Internet.
Mashtastic has a built in Internet connection option called proxy that can use the phone or tablet's Internet to send and receive Meshtastic messages.
Each channel (0-7) has the option to use mqtt, but channel 0 is open key, common to everyone and will swamp your connection - avoid it!
Purists will complain mqtt defeats the purpose of mesh networks. Proponents will tell you how it pulls users together in sparsely populated places.
Kind of like WiresX and repeaters?
Using mqtt is up to the user and can be turned off at any time.
W0AYE and myself (N0QBH) have sent messages back and forth on the W0SW channel (Ben's creation) using the mqtt feature.
Along with it's unique name, it also has a 32 bit key which is shared among the users (by invite). No key, no decode.
I will take this opportunity to point out this isn't Ham radio per say.?
However, there is an option to use Meshtastic under your Ham licence with more power and no encryption.
In closing, I believe mesh networking like this could be a Godsend in a long term power outage when most cell sites go dead and your phone has no service.
At that point in time most phones are a fancy paperweight.?
Mesh users will still be communicating with theirs.
In the meantime, it's just nerdy fun on the leading edge.
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Interesting Mike. ?You say there’s no dumb questions, so I’ll test that theory. ? Could CERT (our Community Emergency Response Team) use this at say, Sibley park on a missing person call, not only to communicate with each other, but to send their location updates to a command post? ?If so, I imagine we would need something similar to what you have on your tower, on the mast of the amateur radio trailer? ?Then to get over hills etc., we may need another one (like on a command post or the regional mobile comm trailer (currently housed in Alexandria), to create a mini mesh network that potentially links back to our Emergency Operations Center (especially if we do internet link)?
 

As I understand Meshtastic, I see no reason why it wouldn't work in a CERT search & rescue operation.
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The small LoRa mesh radio would work with the searcher's phone and both would be on their person.
To use Sibley Park for example, we would position the fixed relay node as high as possible - like Mt. Tom.
This would tie together the smaller mesh networks that would form between the searchers as they move about.
Assuming the searcher's devices all have GPS, their phones could display a map showing their location relative to the others.
MQTT would enhance this by allowing the cellular network to carry this info to the distant command center.
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I'm sure Ben W0AYE can add more to this.
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73
Mike N0QBH
 

Here's a good place to start learning about mesh networking.
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I also emphasize, there are no serious dumb questions here.?
While it's radio and electronics, it's also on the leading, bleeding edge of technology with LoRa modulation.
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Here is a portable Meshtastic node I've constructed for temporary events like a search and rescue or covering a race.
The hardware is identical to my tower node sans the solar panel as the battery alone is good for a few days of operation.
It's purpose is to be a text repeater.
Located reasonably high with a good antenna (for 915 MHz) to act as a relay for the other Meshtastic users.
Depending on terrain and how high up it's located, this should easily cover a couple mile plus area.
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It consists of a weather tight plastic case with a RAK Meshtastic 915 MHz LoRa module, 5 dBi antenna and a 5A 3.7 volt LiPo battery.
The module has a USB C connector for programming and charging the battery. Plugging and unplugging the battery turns it off/on.
A Bluetooth connection lets a nearby event manager manage the node remotely.
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73
Mike N0QBH

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