I am TOTALLY new to LORA and LORAWAN but have an extensive IT background along with various home automation technologies (zwave/zigbee etc). I picked up a LPS8 and a LDS03A with the intention of doing a mailbox notify sensor because our mailbox is about 1/3 of a mile away. I have the open/close notification from the sensor working on my LDS03A and I see the MQTT messages ok. The problem is, I took the door sensor out of the house yesterday to see if I could reach from the mail box and nothing. I came back 1/2 way back up the drive, tried again, nothing. I pulled up to where I could see the house from the car, tried again - nothing. Also of note - I’m in a VERY rural area - it is hilly and very wooded. Get back in the house, try and sure enough, it works.
I feel like I’m missing some kind of transmission power setting or some kind of setting somewhere. I’m so new I’m not sure where to troubleshoot and got to wondering if the LPS8 is not enough gateway/range for sensors like this. Reading indicates it ‘should’ be from what I can tell, but maybe I’m wrong. The LPS8 is sitting on a dresser in my bedroom (aka - the highest point in the house where I have ethernet). I’ve checked the antenna on the LDS03A and it appears to be connected. Any ideas/tips/tricks?
I’d appreciate any help anyone can offer or documentation on how to troubleshoot signal strength etc. Thanks in advance, I appreciate any and all help!
You would get a far better idea of whether there is a range issue, if you put the Gateway on a windowsill so that the gateway antenna has a very clear view of the outside world.
Then, when outside, how far away from the gateway\window, does the door sensor work ?
Is there clear line of site from deployment point to GW or are you seeing terrain masking, extensive woodland or - given rural location, perhaps an intervenining metal barn or similar? As Stuart mentions get GW onto windowcill and do a walk away test to see where signal drops. What SF are you using on the node? What is construction/cladding of the property you have the GW in?
Thanks for the input Jeff-UK! IT is not a clear line of site down to the mailbox - it’s at the bottom of the hill (with a pretty medium to semi-steep rise). When I tested from the driveway where I could see the house (specifically - I could see the room from the driveway that the LPS8 is located in) - and there’s a few woods there - but I can see the house easily. There is no metal barn etc in the way. As to SF - on the LDS03A - it looks like all packets are coming in on SF 10. Let me know if more info is needed etc. n Oh and I forgot - standard stick built home with wood/drywall where the GW is located.
From your description I suspect you are experiencing something like this…
Only solution then either get GW Ant higher to see over terrain or get ant on Mailbox higher to shout up the drive above ground level! …Or you might get something acting as a reflector opposit the house (I shouldn’t laugh as it sometimes does just that! - LoRa signals can be very resiliant )
Try the rolled up magazine test. Roll up a magazine, stand by the mailbox, look at house through magazine as it were a telescope, if you can see the window, all good, otherwise, go to plan B.
If you have a telescope, it’s OK to use that. Or binoculars.
Not uncommon to find the drywall/plaster board + any intervening foam insulation is foil backed which can severely constrain signal - hence get high or atleast clear on a windowcill…depending on glass, thickness, coatings, #of layers etc.you might loose 4-14+db attenuation all the same
That’s a PERFECT drawing - you should work for the police as a sketch artist! Well done! I don’t understand though why when I could see the house from the driveway and tried I also got nothing. I’d buy in easily on the hill - this point is the one driving me crazy. However, I do need to move it to a windowsill when I get a chance today. I’ll report back with this test info as soon as I get a chance. I don’t mind mounting an antenna above the house if needed, so might be in the cards. Maybe I misunderstood LORA - but considering it’s distance is supposed to be a lot of miles, but I’m only going 1/3 of a mile (admittedly heavily wooded and hilly) - I didn’t think signal would have been much of an issue.
Also of note - I tried one of these first before getting into Lora - it would ‘just barely’ work when I’d get close the mailbox, but not enough to do the job.
Roger that - can’t see the house from the mailbox for sure. So plan B it is - which I think will be at least testing outside close to the house and windowsill placement.
Gotcha - to add to that - the windows the GW is sitting in also have tint we just put on the windows with stainless steel in the tint (heat rejection) - so that also may be hindering the signal. I can put the GW on the back porch for now and use wi-fi as the backhaul instead of the ethernet and see how that goes.
Its not just LoRa, distances for all type of UHF communications can vary hugely, depending on the terain.
A high altitude balloon might be picked up by a gateway at 832km, the current record, here the balloon will have direct line of sight to the gateway. But at ground level in an urban area the range might be 1/1000th of that, such are the vagries of UHF communications.
Which I’d agree with - I know it can vary a lot - but I figured rural area, hardly any other stuff around me and 1/3 of a mile to mailbox would have been a cakewalk for Lora - but I didn’t assume it would work like instantly/easily. Hoping to adjust
Remember radio at these frequencies - like light - effectively travels in straight lines, diffusion, scattering, reflections, knife edge effects/diffraction etc. not withstanding! My house is in a similar position to yours at the start of the roll off of the terrain from higher flat hill down into a valley below…I can get a LOS signal 4 or even 40km away but struggle to reach the car park at the parade of shops shadowed by my hill at ~400m! due to the curve of the terrain 100-200m away from home, 600m - further out into the valley bottom - the signal is 20:20 !
This means abt. 50dB additional attenuation, the free-space attenuation is already 85dB, you have abt. 130dB available. (attenuation measured Black Forest in South-Germany 10dB/100m at 868 MHz).
The Fresnel-Zone (zone around the line of sight) seems to be strongly disturbed by the forest and hills. Hard to say how much additional attenuation this means.
Is it possible to put an antenna on the roof or the LPS8 on a higher floor?
if I have to mount an antenna, I’m ok to do that - so that’s definitely an option - as I’m SUPER new to all of this, like how high estimated would I need to go (10 ft above house etc?) - it’s ok if you or anyone else can’t tell me the amount, I’m just kind of feeling out the idea of how high.
The answer is simple: as high and as free as possible. Do not use an antenna with a high gain, 2dBi-5dBi is sufficient. But I cannot promise that it will work. You just have to try it.
Use a good cable between gateway and antenna. For the first experiments you just can put the LPS8 on the roof.
Have fun!
I like it @wolfp - I’ll take it up on the roof and power it up and see how it goes. 1st thing first, just getting it to work ‘outside’ which has not really happened yet. So we’ll try outside and see if I can get signal from the yard and then we’ll work on moving out and higher from there.
…Or you might get something acting as a reflector opposit the house 
(I shouldn’t laugh as it sometimes does just that! - LoRa signals can be very resiliant 
)
