Limit the number of lora channels when joining and sending data

[christiancattlescan]

Hello ST experts,

The board I am using is the LoRa-e5 by seeeed studio. https://wiki.seeedstudio.com/LoRa_E5_Dev_Board/

The premise is that I am creating a LoRa end node that sends an array of data every 30 minutes and the gateway we use only uses the 2nd sub-band (channels 8-15). The example I'm building off from is from STM32Cube_FW_WL_V1.1.0 with the example application LoRaWAN_End_Node. I have asked Seeed studio for support but they redirected me to here. 

I have managed to get the example to work where it successfully joins and sends demo packets every 10s.

The issue:

I noticed that while it attempts to send every 10s, it sends it to channels that our gateway does not use. I found that I can turn on Hybrid_mode in the file lorawan_conf.h to limit the channels to 1-8 but this does not allow my device to join as our gateway is only limited to 8-15.

I then found that we can change the channels default mask to properly adjust for channels 8-15 in the file RegionUS915.C.

However, while I was searching on what to properly set it as, I came across someone mentioning to that the device can't be certified if we plan on making changes the default masks (link).

This product needs to be certified so how would I be able to limit the channels used on my end node? I would like the data to only be sent to the proper channels as I would be missing some data every 30 minutes. I also can't increase the frequency at which it sends data as this drains the battery tremendously. 

Looking to any experts for insights. Thanks in advance.

Christian

[Tesla DeLorean]

>> I have asked Seeed studio for support but they redirected me to here. 

I'm not sure you're going find substantive, do-your-job, type of support here either.

For contractors, perhaps look to Fiverr ? Try the FAE out of your local ST / Wireless office? Perhaps they can point you at contractors with relevant experience in your area.

Is your Gateway actually compliant? What Region settings is it using? Ask them how they managed compliance / certification.

[christiancattlescan]

Hi Tesla,

The gateway we use is from Laird RG1xx and the region we use is US915 so It should be compliant. When purchasing these gateways, we can opt to buy the 16 channels or 8 channels so that's why i believe they are compliant. 

The LoRa-e5 is similar to the stm32WLJC SDK so I am looking for guidance on how I can create an end node without looking needing for contractors. Hoping someone with similar issue can shed some light.

Christian

[Tesla DeLorean]

Gateways tend to use different chips that can concurrently receive multiple channels, and be able to receive and transmit at the same time, with assorted bandwidth and spread factors, etc. ie SX130x devices, rather than SX126x half-duplex, single channel, ones.

Compliance, perhaps you support multiple modes of operation with the primary REGION setting matching those of the GATEWAY, and a power saving one that searches a more limited subset, via the masking, or one that can be set to a specific channel the gateway is parked on or monitoring?

Generally experts in the MOTOR and WIRELESS spaces are more specialized and you're paying for that knowledge to reduce the amount of time you have to spend on it.

Or speak to your COMPLIANCE and CERTIFICATION lab about what options you have to meet the requirements to pass.

[Tesla DeLorean]

Multiple channels at the GATEWAY allow for it to deal with traffic for multiple client nodes, that can all want to be handled at the same time. You're switching channels at the NODE to find a open connection to an available gateway.

Going to depend a lot on the amount of traffic on your network, and how you can synchronize that or not. You could likely use a subset of channels, or one, but then you'd need to be persistent to get data out, or be willing to lose data occasionally.