Using LoRaWAN yagi antennas to increase directional range

1

I want to send telemetry from a weather station A to an internet gateway B, about 300m apart but not line-of-sight. However, both sites can see a third site C, about 2km away.

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I’m thinking to send the telemetry with LoRa transceivers (SX1262), from A to C to B using yagi antennas to achieve the necessary range.

Would this antenna be appropriate (in Canada)? https://www.amazon.ca/gp/product/B0CM1CHRJK/ref=ox_sc_act_title_1?smid=AYCXRUP942PA5&psc=1

Also I would be grateful for comments about this approach.

2

Dont know the precise details for Canada.

But be aware that there are normally effective radiated power (ERP) limits for transmissions, so adding a ‘gain’ antenna will often increase the ERP beyond legal limits.

And for this ‘telemetry’ which TTN server are you using ?

3

Ah I see, this sounds like point to point LoRa using SX1262 devices, so would be an off topic discussion for this TTN\LoRaWAN forum.

4

nearly worth while just trying to see if you could work a-b

I know you say no los most probably a hill in between

less kit less to go wrong less maintenance

5

Personally I’d put a solar powered repeater on the top of the big hill preventing LoS rather than ending up with kit on two different islands.

But all rather moot as this TTI funded forum is only for the discussion of LoRaWAN & its use on TTN/TTI services.

@sidtupper, you could try paging @LoRaTracker over on the Arduino forum to take this further.

6

Thanks for your response. Please suggest a better forum for my post.

I want to be legal so I mean to transmit at reduced power and expect that the antenna will be adequate at the receiving end. So your thoughts about the adequacy of the antenna referenced in my post would be helpful.

As for the telemetry server question, my plan is to command the SX1262 transceiver from the computer (RPi4) that’s reading the weather sensors. The duty cycle would be tiny since the data (< 256 chars) needs to be sent only every 5 minutes.

There’s a helium hotspot 2.7km from site A (weather station). It’s the closest by a large margin. I’m not clear on how helium hotspots work. Could I send my data there so that it’s forwarded to an internet site? Reliability would be an issue. How can I communicate with the operator?

7

Thanks for the suggestion. I’ll try direct A<->B. You’re right, there’s a lot of granite in the way.

8

Point missed maybe.

LoRaWAN is a two way system and nodes need to transmit as well as receive.

Whilst a gain antenna at the receiving end will increase the apparent reception ‘range’ the recieving end will have to reduce the power level it uses to transmit (to stay legal) so the gain of the antenna is nullified. You have in effect created a receive only system, which is not LoRaWAN.

At maximum range spreading factor, SF12, that data rate would be around 2.5 times the normal allowed duty cycle (1%) and about 70 times the TTN fair access limit.

9

P2P not being a topic for this forum - point missed maybe?

And we don’t get in to Helium either.

Closing the thread - as I suggest, the OP could try the Arduino forum but looks like some overall learning about LoRaWAN is indicated - hotspots/gateways that are public you can just use - no operator interaction required - and for LoRaWAN, 50 bytes is a fair amount and on TTN, 50 bytes over 2km may well exceed the Fair Use Policy - so much to cover.

Closing as getting way off TTI funded LoRaWAN.