I’ve had some success with the TTN indoor gateway and an RPi based gateway but distances seem to be very short in promised Lorawan terms. I’ve tried a much better gateway antenna and raised the height above roof level, but with limited improvment.
I am using the RN2483 end device and my question relates to two commands “Radio Set Pwr” and “Mac Set Pwridx”
Do these parameters inter-relate or are they independent (my reading of the Microchip documentation seems to imply they have very similar functions).
Are the changed values only stored in a temporary way ?
My objective is to try to find ways of improving range, having already tried changing data rates.
Please quantify distances, SF, tell which kind of environment, height of the gateway… if you aim at 20km, you need a decent, elevated outdoor antenna. However, with a single channel gateway and a GPA indoor antenna under the roof I occasionally reached 6km (not the norm).
Acting on the node power is not a way, also because is limited by law.
Thanks UdLoRa,
I am only getting distances of a few hundred metres (nowhere near a Km). I am on the edge of an industrial area with the antenna at about 7 to 8m from the ground and about 1m above a flat roof building.
I am testing outside of the industrial area and in an elevated rural position that allows line of sight to the antenna. Even in these conditions the range is only in the 100s of metres.
I have had success with other wireless technologies (e.g. Zigbee) with a small stub antenna that has reached these distances in this location without the need for the “gateway” antenna to be elevated or large. (I understand Zigbee is a very different technology but I add this just to give a little context).
This is the reason I am enquiring about the power setting and trying to understand the meaning of the two power configuration parameters.
I appreciate the maximum legal transmitted power situation but the device (as I understand it) is limited to stay within legal limits and settings are available to reduce the power output to enhance battery life.
I was wondering if I was somehow mis-understanding the meaning of the two parameters, though I have tried numerous variations and also variations in SF from 7 to 12.
I have noted others have had issues with limited range whilst many seem to have excellent results.
Having tested my arrangement with others (to try to ensure there are no “idiot” issues), I am now wondering what else to do.
I have tried two distinctly different gateways with no difference in the results and so now focussing on the end device. I have also tried two different high gain antennae.
The end devices which are the Microchip DM164138 (Demonstration Board, RN2483 LoRa™ Technology Mote, 868 MHz).
Any further comment greatly appreciated.
In my opinion, most of those that had issues with limited range expected too much from poor indoor antennas (like me initially). My first single channel gw was a Dragino hat on a RPi and spent a lot of time with its ridiculous original antenna…
However, your setup seems to be adequate for reaching more distance. I just checked yesterday data (just installed a TTIG), and reached 2.6Km, gateway indoor at 2m height, 2nd floor, and a tracker with SMD antenna as node.
Do you have just one end device or more? because my thought at this point is some hw issue (node antenna, its connection… verify SMA vs RP-SMA for example, silly but someone had this problem).
Do you check RSSI and SNR? How are when close to the gateway?
If you can actually see the antenna, then extreme short range is one symptom of LoRa modules with damadged transmit stages, as can happen if your chaging antennas a lot and turn the device on with no or a faulty antenna.
Knowing the power output of you module would be what I would want to investigate, you can get an indication with a very low cost SDR. But you really need a known good working module to compare against.
When quoting distances try to be specific, you may know what ‘100s of metres’ means, the forum does not.
Environments and circumstances vary so much that the range for the avaialble (and legal) hardware could be 500m or 5km. Difficult to promise anything in those circumstances.
Thanks both.
Regarding hardware issues, I have tried two of the Microchip modules, one at a time and together.
No issue with uplink or downlink in any arrangement at close range.
The antenna used in each case was that supplied with the device and was attached prior to power, as per the instructions.
I have not got any specific RSSI or SNR values but will try to obtain them.
Regarding distances: of course the actual distance is important but I was trying to impart the fact that it was far less that a Km. This would vary depending on actual orientation to the antenna due to factors such as elevation, vegetation etc. However the distance was in the range of between 150m and 300m which appears to be significantly below expectations.
However, back to my original question … does anyone understand if there is a relationship between the two commands “Radio Set Pwr” and “Mac Set Pwridx” on the RN2483 ?
Just look at the console. It is important to know these values, if not is difficult to understand.
according to the RN2483 manual, the latter refers to an array of values defined in the LoRaWAN specification (here). So one sets according to LoRaWAN definitions, the other sets in dB. However, if you do not know RSSI of received packets, it does not make sense to just play with these values…
Thanks again UdLora
I’ve got RSSI and SNR values now and will do some further tests.
I appreciate your point about adjustment of power, but I am trying to ensure I understand if these two values interact in some way e.g. does one take priority over the other somehow ?
I’ve read the spec but it is more to do with how these config parameters have been implemented by Microchip on the RN2483
Thanks LoRaTracker
Yes, it does seem that I have a fault somewhere, but after two different gateways, two end devices, two high gain antennae and a lot of testing I thought I would just ask the community to see if there was someone who has had similar issues and found the “obvious” answer.
I am only using the Microchip dev device “out of the box” at the moment and it clearly works at short range.
I’ll try a completely different location and see if there is an improvement and then try to track down the issue.
I expect the last you use will set the power, at the end you have just one radio chip. Likely, MAC commands are LoRaWAN specific and ensure compliance, radio commands maybe could be used for pure Lora too.
However, do you have the software that runs on the node? check there what is used for setting power… so you will be also sure about the level set as default.
It’s worth checking that you are not over modulating. I once spent a very frustrating afternoon trying to get a WhisperNode to work, only to find that the issue was I was too close to the gateway. Reducing power to minimum solved the problem.
Regarding the two commands, my interpretation is that they are effectively analogous to each other in their effect, however, the the set pwridx command allows the output power to be expressed in units meaningful to the LoraWAN specification. So, if you’re using a LoRaWAN specifically, you would use this command. If you using LoRa MAC (i.e. rolling your own protocol on top of the LoRa modulation technology) then you’d probably use radio setpwr.
Hi LoRaTracker,
Just to mention I had a quick look at your “KISS” paper whilst looking through other docs… interesting.
I see you were in South Wales… at the time.
Do you have a gateway setup in the area ? I could (perhaps) try my end device on your gateway if it is open, as I’m also in South Wales.
Hi Aagin,
all I am doing is “talking” to the device using RealTerm over a USB connection … it seems to be accepting all the commands and works fine at short range.
I see your point, but I’m finding no issues when really close (0 to 10m) (RSSI -87 / SNR 9 / SF 8 / airtime 103mS).
It’s just that performance drops off quickly. Just tried inside the building and only got about 25m (RSSI -126 / SNR -10.5 / SF 11 / airtime 741mS)… but it is an old building with concrete and steel.
I’m going to change location completely and see what happens.
As example, in this moment I have a TTIG gateway indoor 1st floor, and a couple of trackers inside my car, at about 10m (something more). The one with the best antenna floats around -45; the others are around -60.