Gateway queries & ranges

Hi @sronan,

I did however as mentioned the online one doesn’t do 868 Mhz for EU Frequenices.

But instead found another site which has a free trial. If I’ve entered all of the details right my expectations of a few KM should be right.

Screenshot from 2017-12-26 15-21-54

So far though with the new antenna I haven’t got far enough away yet so need to set up a node in my car and drive around.

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F292371508852 the seller seems to construct the antennas. The one I received had the best measurement results from all different antennas I got. Measured with a R&S FSL.

Hi @moeterbln, That’s the antenna I’m using which so far has got the best results as well. What type of range did you get?

I got 3,5km using SF7. Unfortunately the surrounding terrain is a little higher than my house. The main problem are houses etc. Line of sight is nearly impossible. But for the place I’m ok with the range I get.

1 Like

@moeterbln Thanks. I have a similar issue but I’m not in as dense of an area. However most of the area is on a lower altitude than where I am.

1 Like

Update:

A mix of the new antenna, It being put up higher and other improvements have ment the range is much better. I’m still mapping it out however am now picking up signal from between 2-4KM, Much less than the 10-15 KM most devices claim but more acceptable in my view.

I blogged about it at http://ryanteck.net/adventures-in-lora-2/

1 Like

Watching your journey with interest, it takes time and there are limitations - pro’s and con’s of both flat land areas and hilly areas - we are on the edge of the South Pennines (Sheffield) at 250m and I can get 6-10km on SF 7 but that is with perfect line of sight in a hilly area, the downside is I take a massive hit in terms of scope due to hills getting in the way. Its crazy for me in a way, I can stick a gateway on the top of a hill at 400m, I can then receive packets from 10km away and yet cant get SF7 from 300m in the bottom of the valleys due to line of sight issus! (SF8 up to SF12 do start help in this situation)

Read your blogs, your dont mention Spreading Factor once, SF12 whilst with its issues (again pros and cons) can literally bend around land masses and objects and so moving off SF7 will start to open up more distance, and pros and cons from SF7 to SF12.

Claims of 10-15km are easy to achieve with clear line of sight on SF7, but these are perfect world figures.

Also remember you have two way communications to consider, its one thing sending a packet and its another receiving one, your node setup, node aerial, the nodes lora module type, your code too will all impact what you can achieve.

All good fun :slight_smile:

@jezd,

Indeed I haven’t mentioned Spreading Factors. I have been using 7 since according to the guides you shouldn’t program something to use SF12 as standard. I also believe the LoPy I’m using doesn’t support it. (And I’ve not been having luck re-programming my LoRa32u4 with constant arduino bootloader issues).

For now I’m going to continue mapping at SF7 which is also in line with TTN Map’s and then increase to SF12 once I finally get the Arduino sorted out to transmit on that and submit it as an experiment to TTN Mapper. Realistically my plan is to map it out at SF7 which covers most of the actual housing area and then experiment with higher SF Rates.

Are those claims based on use of SF7? I’ve seen documentation suggesting those claims are based on SF12…

There are values between 7 and 12… using SF9 is perfectly valid (or better, for stationary nodes use ADR)

That would surprise me as LoPy is LoRaWAN compliant and SF12 is part of the specification.

Hi @kersing,

I think I’ve seen claims of 10KM on SF7 but I can’t remember.

As for it being LoRaWan Compliant most sources I find say that devices set to use hardcoded rates of SF11 & 12 or constantly transmit on them should be blocked. As of this LoPy doesn’t allow the SF to be set when in LoRaWan mode. Weather it changes dynamically or not I’m not sure. This could be because I’m using ABPP rather than OTA.

Where is it saying this? its not simply about the SF (look at the gateway console for the dramatic airtime difference between SF7 and SF12) but equally about frequency of usage over a period - lorawan specs are clear

Your making its sound like SF12 is not allowed to be used which is simply untrue, you could use ADR once your finished testing but seeing as your just testing at the moment there is nothing wrong with working across the SF levels to see what range you get.

I’ve found the cheap LoRa32u4 have better performance than other nodes.

@jezd, This post is one of the first to pop up for example - Can I register an ABP device that has fixed DevAddr, NwkSKey and AppSKey? , If I’m reading it right even with ADR using SF11 & 12 is frowned upon if its all the device can use.

As for trying out the LoRa32u4 vs the LoPy I sure plan to once I stop experiencing issues with the arduino IDE.

13 km :sunglasses: but that’s because LOS and my antenne (5 dbi) is @ 18 mtr and the receiving gateway @ 35 mtr
but with no LOS with a lot of buildings in between I have a confirmed 2.8 km @sf7

Update,

My SF7 testing this morning was terrible, I think this was because I changed to using OTAA instead of ABP and I don’t find it as reliable so I need to do this again.

I did some testing at SF10 and got peaks of ~ 5KM from the gateway with an average of 4KM. I’ll be doing some more mapping over the next few days.

Once joined, an OTAA device should behave like an ABP device. (The device should only join once and then keep using the very same DevAddr and secret keys just like an ABP device would, until it somehow loses them.)

3 Likes

Interesting. I’ll have to try that out as I do seem to get better range for whatever reason in ABP Mode. No idea why.

Screenshot from 2017-12-30 22-14-28

For reference so far I’ve plotted this map. The inner green circle so far has been a clear good signal zone, Orange and yellow are patchy. Red is the peak I’ve got at SF10.

Blue is the theoretical 10KM. Just rather interesting. I hope that by documenting it here & on my blog it’ll help some others out with realistic range expections.

2 Likes

OTA requires the node receives a downlink join accept sent by the gateway, if your node does not receive this then you wont get results - in terms of wardriving tests OTA tests your two way connection in effect, ADR will simply tests your node transmits only

Only when ‘starting’ the node. Once it has its keys it can use them as long as you don’t loose them (power down/reset).

You should never OTAA for each data transmission because you will a) use airtime of the gateway unnecessarily and b) you will run out of nonces resulting in OTAA failures. (B does not apply to LoRaWAN 1.2 compatible nodes on a LoRaWAN 1.2 network)

1 Like

I thought I’d do an update for this post.

As for range of ABP vs OTAA I’ve not done any testing but ABP is slightly more reliable in my case.

I’ve been trying at different spreading factors and am getting a more acceptable range. I’m hoping I’ll be able to extend the pole which I have my antenna on for extra height and will be moving the gateway outside so the cable even though the antenna will be higher won’t be any longer as currently it goes indoors.

I just wanted to check, is RG8 Mini suitable cable? This is what I used as I believed I was buying RG8 which has a slightly different datasheet to RG8 Mini that actually arrived but I didn’t notice it until I put the antenna up as is.

Like mentioned earlier above: the range will be exactly the same.

2 Likes