LoRa Node->Node chip reccomendations 2024

doug42
Fri, 27 Sep 2024 15:58:13 +0000
Hardware

Hello!

I am working on a smart energy metering project for a charity tackling on energy poverty. I am an engineer jack of all trades dunce of many and LoRa is something I have been aware of but until now never tinkered with.

I am about to try and race through that learning curve but I was hoping someone more knowledgeable might point me in the right direction hardware/ strategy wise so I am less likely to spend time learning the nuances of a chip that I would never use.

I need to avoid LoRaWAN as the grid needs to keep operating with or without internet and it would be preferable to avoid the extra communication overhead, complexity and points of failure that it introduces

End Goal:
50-100 nodes transmitting ~64bits worth of data / second (cold be reduced to every 5 seconds and could be accumulated and sent every 10-20 seconds) to a central hub up to ~2Km away. I plan to have the meters mounted at the top of the transmission poles for tampering and signal reasons.
Deployment: pacific Island nations. in the future west Africa - Im aware that this might require a second version for frequency band reasons.

So far I am leaning towards:
SX1262 or SX127x Family + RP2040
But there are many choices and I am still at the learning point where the spec sheets are partially Chinese to me. I’m not sure of the most important specs for my purposes. There are also many other manufacturers.

I know this isn’t exactly the first time this particular wheel has been created. Sparkmeter.io being one example but we would like to avoid hardware vendor lock in and subscription fees that usually come with these systems not to mention the inability to change, develop or fix the design. I have seen plenty of open source projects in this area but most dont have the same cost restraints. In the end the chip will have to be integrated into the meters PCB. Chips are currently ~$3 on JLCPCB library so hopefully a ~$5 cost added to the PCB once peripherals are added (+antenna obviously)

The chip staying in production for the forseable future would also be a big plus.

So what would you recommend as a starting point hardware wise in 2024 to someone who has not had their eye on this market space?
any rabbit holes you would avoid?
any tips on the most important features for reliability and range would also be appreciated (Or if practically there isn’t much difference?!)

Also if you have any learning resources you like, that would lead me to having a less than skin deep understanding that would be fantastic!

Doug

34 posts - 6 participants