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Problem with LoRaWAN 1.0 mode

  • 3 augustus 2015
  • 5 reacties
  • 1635 keer bekeken

Hi all,

I have a KPN gateway up and running-which works fine with the LORA motes.

However, if I add an end-device in LoRaWAN 1.0 mode, 80% of the packets are not received by the gateway.

For the end device, I use a firmware derived from LoRaWAN in C (http://www.research.ibm.com/labs/zurich/ics/lrsc/lmic.html).

However, ook with the above reference firmware and hardware reference I have the same problem.

My end devices work fine with the Church Link Gateway, loaded with LRSC firmware.

I send periodic one unconfirmed byte packets every 10 seconds.

What can the problem be? What LoRaWAN implementation have been tested and guaranteed to work with the gateway?

5 reacties

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The KPN setup has been validated with the Loramote default software and the Semtech code from Github (https://github.com/Lora-net/LoRaMac-node) it is important to adjust the used frequency setup in the LoRaMac-board.h file as follows:

* LoRaMac default channels
*/
// Channel = { Frequency [Hz], { ( ( DrMax << 4 ) | DrMin ) }, Band }
#define LC1 { 868100000, { ( ( DR_SF7 << 4 ) | DR_SF12 ) }, 1 }
#define LC2 { 868300000, { ( ( DR_SF7 << 4 ) | DR_SF12 ) }, 1 }
#define LC3 { 868500000, { ( ( DR_SF7 << 4 ) | DR_SF12 ) }, 1 }
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Hi vito,

What's the average % of lost packets?

And is this solved when switching to confirmed frames?
@1 there is no technical limitation but you should respect the duty cycle of the frequency band.

A device just transmitted a 0.5 s long frame on one default channel. This channel
29 is in a sub-band allowing 1% duty-cycle. Therefore this whole sub-band (868 – 868.6) will be
30 unavailable for 49.5 s.
@2 In the network there is no policy to drop, it is only marked.

Each end-device has two frame counters to keep track of the number of data frames sent uplink to the network server (FCntUp), incremented by the end-device and received by the end-device downlink from the network server (FCntDown), which is incremented by the network server. The network server tracks the uplink frame counter and generates the downlink counter for each end-device. After a join accept, the frame counters on the end device and the frame counters on the network server for that end-device are reset to 0.
@3/4 Debugging on the gateway is not supported, you can use the ethernet port for sending the packets to the KPN networkserver. As long as there is no proxy in between this should work. This could solve some issue when you expect poor GPRS/UMTS coverage.
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https:///t5/user/viewprofilepage/user-id/962 schreef op https:///t5/Vragen-Toepassingen-Oplossingen/Problem-with-LoRaWAN-1-0-mode/m-p/4685#M46

"@3/4 Debugging on the gateway is not supported, you can use the ethernet port for sending the packets to the KPN networkserver. As long as there is no proxy in between this should work. This could solve some issue when you expect poor GPRS/UMTS coverage."

I am using the gateway in an area with low GSM signal, but also ethernet connection doesn't seem working properly.

Do I need a specific subnet mask for making the gateway transmit through ethernet?

 

The gateway is configured to accept a DHCP offered IP adres/GW, as long as there is no proxy or other settings this should work.
Thanks Pieter.

I have checked the frequencies, they are ok. Still my gateway is logging only part of the packets I send.

  1. Is there a limitation about the number of frames that can be sent (something like 1 every minute?)
  2. What is the server rejecting policy about wrong upcount/downcount? I think, every time I flash my end-device those counters are reset and probably the server rejects the packets with mismatching counter.
  3. Can I use the debug port to see what frames are received by the gateway? That would be very useful to see where the problem lies, maybe the GPRS connection is bad and the gateway doesn't forward all the packets. 
  4. Can I use the ethernet port instead? What are the steps for that? Is there documentation about the gateway?
"@3/4 Debugging on the gateway is not supported, you can use the ethernet port for sending the packets to the KPN networkserver. As long as there is no proxy in between this should work. This could solve some issue when you expect poor GPRS/UMTS coverage."

I am using the gateway in an area with low GSM signal, but also ethernet connection doesn't seem working properly.

Do I need a specific subnet mask for making the gateway transmit through ethernet?

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