How to configure B-072Z-LRWAN1 Ping-Pong example for best distance?

[Selim Sagir]

Hello to everyone,

I have two B-L072Z-LRWAN1 kit. Trying for measure best distance i can reach. I am using Ping-Pong example and change some variables such as LORA_SPREADING_FACTOR, LORA_BANDWIDTH, LORA_CODINGRATE, LORA_PREAMBLE_LENGTH etc. Until now, modules could not connect when spreading factor above 9. So i didnt achieve long distances. Anyone tried or know what is the best configuration for long distances.

Thanks.

[Tesla DeLorean]

Make sure the timeout is adequate for the transmission periods you create.

Try using the LoRa calculator (from Semtech) to understand the relationships rather than plug in values.

https://www.semtech.com/uploads/documents/SX1272LoRaCalculatorSetup1_1.zip

PingPong is probably a poor example given it's metastability, perhaps create a beaconing unit and use that to determine the throw of the radio, or create a local heat map.

[Selim Sagir]

Thanks for answer. Is there any example of ST can make better monitoring for range test. I couldnt find any example. I think i should make own code.

[Selim Sagir]

I calculate timeout then change rxtimeout define but again i cannot connect two kits.

[Tesla DeLorean]

I wrote my own, and used GPS shields to report position.

Zero effort should get you 1KM.

Some effort yielded 5-6KM with nominal settings.

With conservative settings I was able to get out to 14KM, but that was limited by the rather flat topology of the region, and lack of high points or hills to mount things on.

At distance you need line of sight to the antenna.

[YShta]

can you give the code for 1KM?

i tried the ping-pong with less data, SF=12, BW=125K and not get more then 50-70 meters.

[Tesla DeLorean]

Are you in a faraday cage? I would suggest cloning the project, and then create TWO forks, one that PINGS and one that LISTENS

SF=4, BW=250K, CR=1 (4/5), 20dBm, 915MHz

Pretty sure I demonstrated 900-1000m coverage at 500KHz in local business park with an antenna above my desk, perhaps 4-5ft above floor

The 5-6 KM was achieved with a roof mounted antenna, perhaps 30ft above street level, and a 7 dBi antenna on the vehicle mounted receiver.

At SF=12,BW=125K, CR=4 (4/8) I was able to get 14KM, but the bit rate is VERY low. So the timeout needs to be many seconds, depending on how long your message is.

[YShta]

First of all, Thank you for your comment.

The B-L072Z-LRWAN1 work with SF above 6 (according to the example code), i'm using the 868Mhz module and i need bi-directional communication.

I don't understand why it will work good for a beacon and give poor results for bi-directional communication.

In any case, i will check your suggestion.

[BHedo.1]

Hello Yshta,

I got the same result. Have you found a solution?

Regards,

Benoit

[Tesla DeLorean]

You're digging quite far into the way-back machine here..

Perhaps better stating your issue/situation completely, and trying to understand why that's not working properly. For example where you are, what frequency band you're in, etc. You might also consider moving the frequency of the demo within the band, to see if the default is just over congested.

The stubby antenna on the kit is reasonably effective at getting a signal into the air. Height and the structures the signal needs to penetrate are going to limit distance.

#metoo