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JaapBraam / LoRaWanGateway

A LoRaWan Gateway in LUA
MIT License
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OTA issue with single channel gateway #42

Closed tekZip closed 6 years ago

tekZip commented 6 years ago

Hi,

I have been working with the single channel gateway on Australian frequencies using this library. Its a fabulous piece of work that is helping many out there who are stepping into Lora.

I am able to send messages to TTN using ABP without any issues, but OTA does not work.Was anyone able to get this working for OTA.

From the logs i can see the transmit packet received buy the gateway from TNN (transmitPkt), so I assume the gateway is transmitting this. I have also adjusted the receive window on my node to sufficiently cover the transmit timeframe during both the windows, but still not receive by the node. It gets the Rxtimeout. 1st window at 5 seconds and second at 6 seconds.with max window time of 3 seconds.

For the node i am using this library https://github.com/Lora-net/LoRaMac-node I am using the nrf52 as the mcu.

Ive been tweaking and trying since a week, but unable to get OTA to work. Am I missing something? Can you please help?

Regards Arif

JaapBraam commented 6 years ago

If ABP is working, the next thing to test is wether sending a message to your node works. If your node can successfully receive messages sent by the gateway there is no reason OTA wouldn't work. The internal timing of your node is crucial to be able to receive messages, so make sure the timing is right. You also have to check the frequency and SF the node is listening to when trying to receive a message.

tekZip commented 6 years ago

Hey Jaap,

Thanks for your quick response! It was indeed the timing issue. Receiver was set at the right frequency and SF, however the symbol timeout was too short and once I extended that, the node started to receive the downlink.

Also, there was one more issue subsequent to that. The way the lorawan stack is set up, the low data rate optimize had to be tweaked to set to 1 for SF12. Once I did this OTAA started to work!!!

I think you've done a great job building the firmware for single channel gateway, as I only needed to use existing esp lying around rather than buying an expensive gateway :)

Regards Arif