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New LoRa RF distance record

thethingsnetwork.org

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Re: New LoRa RF distance record

#61

Post by pmuk »

johanstokking wrote: post #15

CTO & co-founder of The Things Network here! I've been working with LoRa for over eight years now, and I keep getting surprised by measurements like this. What started off as "line of sight works" went to a successful "LoRa moon bounce" [0] and now a sea level reception over 830 miles. So, any physics people here care to comment how this works? Is this pure atmospheric refraction or is there something else? [0] https…

I've just disconnected a BobCat miner so I have a spare 1.1m 8.5dBi 868MHz antenna on my roof. Can you recommend a good gateway to get started on TTN?

Re: New LoRa RF distance record

#63

Post by dbrgn »

H8crilA wrote: post #54
dbrgn wrote: post #50

Earlier quoted context omitted.

Could the signal bounce off airplanes as well, or is that effect not relevant in practice? (I think I've heard such stories before from radio amateurs...)

It can bounce off of meteor trails or the moon. It's been done many times in the ham community. Signals do bounce off of aircraft too, there are even passive military radars that track airborne objects using DVB-T or other strong signal reflections. It could be used if the conditions are just right. All of this has really nothing to do with LoRa and everything to do with physical properties of the emissions (frequenc…

Yes, of course this is related to the physical properties of the emissions, but LoRa uses specific frequencies of the ISM band (868 MHz in Europe), and this discussion was about the reasons why that specific LoRa transmission worked even though there wasn't a line of sight. Airplanes could be an explanation, although your sibling comment thinks there isn't sufficient transmission power for it to be feasible.

Re: New LoRa RF distance record

#64

Post by tlamponi »

nickcw wrote: post #43

LoRa runs in the 868 MHz band (in Europe) - a frequency range known for being line of sight only as the ionosphere doesn't reflect radio waves of that high frequency. However sometimes you can get Troposheric propagation on these high frequency bands. This used to be common when I was a teenager living in the south of England in Kent and we could occasionally receive racy TV channels from Europe. https://en.wikipedia…

> LoRa runs in the 868 MHz band (in Europe)

No, LoRa can run on two bands in Europe, either EU433 from 433.05 to 434.79 MHz or EU863 from 863 to 870 MHz.

See e.g., https://www.everythingrf.com/community/lora-frequency-in-eur... or https://www.thethingsnetwork.org/forum/t/is-there-an-agreed-... or for a more dense, but definitive source https://docdb.cept.org/download/4316 ("EUROPEAN TABLE OF FREQUENCY ALLOCATIONS AND APPLICATIONS IN THE FREQUENCY RANGE 8.3 kHz to 3000 GHz (ECA TABLE")

Albeit I'm not sure what band they used here.

Re: New LoRa RF distance record

#65

Post by pimterry »

jacquesm wrote: post #21
johanstokking wrote: post #15

CTO & co-founder of The Things Network here! I've been working with LoRa for over eight years now, and I keep getting surprised by measurements like this. What started off as "line of sight works" went to a successful "LoRa moon bounce" [0] and now a sea level reception over 830 miles. So, any physics people here care to comment how this works? Is this pure atmospheric refraction or is there something else? [0] https…

[flagged]

This seems bizarre to me, as this isn't astroturfing at all - it's a marketing post on the official company blog! There's no suggestion whatsoever that this is coming from raw grassroots enthusiasm. This is clearly marketing content directly from the business itself.

To be clear, that's fine! This is definitely interesting content, and companies with genuinely interesting things to share should share them directly, that's great. I can't speak for the wikipedia behaviour, but I think complaining about this post is unreasonable.

Re: New LoRa RF distance record

#66

Post by dgacmu »

dbrgn wrote: post #51
Svenstaro wrote: post #42

Earlier quoted context omitted.

I did this once as a small experiment. Basically use a small TCP stack with LoRa as layer 1 and then expose the whole thing as a Linux kernel module. It was a bit shitty but it seemed promising. For some reason, I don't find LoRaWan at all alluring. As far as I can tell, in the end it's in the hands of one company and that really defeats the spirit for me. I mostly just use LoRa for point-to-point connections with my…

At least on 868 MHz, if you stick to the 1% duty cycle limitations that the ISM band allows, I doubt that you'll be happy with the web surfing performance. (For those that don't know duty cycle limitations: https://www.thethingsnetwork.org/docs/lorawan/duty-cycle/ )

This may be an EU duty cycle vs US time per channel thing? In the US you can frequency hop to get higher performance (the limit here is no more than 400ms per 20s per channel), which seems more aggressive than the 1% power sub-band EU rule (but ianal and I haven't read the EU rules carefully).

Re: New LoRa RF distance record

#67

Post by fiddlerwoaroof »

jacquesm wrote: post #21
johanstokking wrote: post #15

CTO & co-founder of The Things Network here! I've been working with LoRa for over eight years now, and I keep getting surprised by measurements like this. What started off as "line of sight works" went to a successful "LoRa moon bounce" [0] and now a sea level reception over 830 miles. So, any physics people here care to comment how this works? Is this pure atmospheric refraction or is there something else? [0] https…

[flagged]

> Please don't post insinuations about astroturfing, shilling, brigading, foreign agents, and the like. It degrades discussion and is usually mistaken. If you're worried about abuse, email hn@ycombinator.com and we'll look at the data.

Re: New LoRa RF distance record

#68

Post by zikduruqe »

johanstokking wrote: post #15

CTO & co-founder of The Things Network here! I've been working with LoRa for over eight years now, and I keep getting surprised by measurements like this. What started off as "line of sight works" went to a successful "LoRa moon bounce" [0] and now a sea level reception over 830 miles. So, any physics people here care to comment how this works? Is this pure atmospheric refraction or is there something else? [0] https…

A CTO that doesn't understand RF and has been working with it for 8 years?

Re: New LoRa RF distance record

#69

Post by goodpoint »

Svenstaro wrote: post #24
wienke wrote: post #12

Earlier quoted context omitted.

For sure would be great but LoRa has limitations as it is designed for small sensors that sent very little data: https://www.thethingsnetwork.org/docs/lorawan/limitations/

You're looking LoRaWan which is not the same as LoRa. In fact I believe web browsing to be quite feasible if you just use LoRa with your own network stack.

Not at all. The effective speed is extremely low due to the duty cycle.

Re: New LoRa RF distance record

#70

Post by wienke »

pmuk wrote: post #61
johanstokking wrote: post #15

CTO & co-founder of The Things Network here! I've been working with LoRa for over eight years now, and I keep getting surprised by measurements like this. What started off as "line of sight works" went to a successful "LoRa moon bounce" [0] and now a sea level reception over 830 miles. So, any physics people here care to comment how this works? Is this pure atmospheric refraction or is there something else? [0] https…

I've just disconnected a BobCat miner so I have a spare 1.1m 8.5dBi 868MHz antenna on my roof. Can you recommend a good gateway to get started on TTN?

Recently somebody created this guide to turn your Helium gateway (running on a RPi) to a TTN gateway: https://medium.com/@friedkiwi/repurposing-helium-iot-hotspot...
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