LoRa transmission from low orbit satellite during The Things Conference

N2YO is showing passes at 22:41, which will be low in the sky for London/Amsterdam, and 00:17 over Ireland, which is technically tomorrow. Where are you getting 13:35 from?

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1 minute!

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What did he win? The telex printer used during the conference? :sunglasses:

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The previous one was very short…

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Telex has captured a few packets just now.

It’s mid Atlantic at the moment, about 5 degrees off the horizon. Is that receivable?

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Ack. Last pass starts at 23:35:06 CET.

There is a low elevation pass at 22:03 as well (2.3 degrees above the horizon).

Unfortunately I did not.

I have a nice node to play with when I get home.

I will post the receiver code at some point, it can be useful to have a simple receiver that can easily configured for different LoRa and frequency settings and can log packets as ASCII and hex to terminal and SD card. The code should run on most Arduino platforms.

We now know that LoRa can be received from low earth orbit with very simple ground based equipment.

And thanks to Thomas for such an interesting challenge.

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Last message was received in Delft last night (1 degree elevation):

TTNSAT-1 2018-02-03 22:47:55.864 goodbye!

It was great, thanks all for your enthusiasm!

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Thanks for the challenge Thomas,

I attempted to receive the messages from space. Unfortunately I received nothing with my setup. Probably my antenna setup was too simple. I colocated an aircraft antenna (120 - 140MHz) with the TTN node on the balcony. So wrong frequency and probably also wrong polarization. I did not have time to create a more sophisticated setup. You know… busy busy,…, but it was fun to try! :smile:

It would be difficult to come up with a matching challenge for a next TTN event.

Cheers, Ivo

BTW, what was satellite’s TX power?

BTW for those of us not at the Conf what was the ‘secret message’? (Just curious!)

The message is in the video, but the code is masked there:

The xxxxxx showed some numerical code during Thomas’ presentation, either accidentally or on purpose, at which point the challenge kind of ended :slight_smile:

Hopefully next year Thomas’ / http://www.lacuna.space/get-involved/ has launched at least one satellite with the LoRa stuff. No pressure, @telkamp :wink:

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26dBm into an approx 6dBm gain antenna I believe.

Anyway just off to the Flying Dutchman near Amsterdam Central station for a ‘few’ beers.

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Well done! I couldn’t find the story behind it… Did this satellite use some sort of software-LoRa on an already present radio transmitter?

At the beginning of this thread:

It was an interesting experiment. I tried to receive it a couple of times with an RFM96W/433 module (from London) but no luck. I didn’t really expect it to work but wanted to try anyway :slight_smile:

A major achievement, congratulations.

I noted on Saturday that reception started just as soon as TTNSAT appeared above the horizon, it looks like at a distance of 2760km or so.

What was the SNR reported at this time ?

You could then estimate what maximum data rate you could get, above the 293bps that TTNSAT was sending.

Do you know the gain of the antenna on the TTN building roof ?

I was trying to capture the 162 MHz signal from home (Zürich) with an SDR, but my line-of-sight and antenna were sub-optimal. Bart Root (https://twitter.com/Bart_Root/status/958985584130879488) kindly gave me a copy of his SDR recording, in the form of an IQ file, which I have been trying to replay on a LimeSDR transmit channel on 868MHz and decode using a LoPy running a LMIC-based LoRa listener, but with no luck…

I would like to find out what in that chain I did not have working properly. Now that the competition is over, would you mind sharing (part of) the IQ file that the satellite was loaded with, so that LoRa & SDR enthusiasts can try completing the challenge?

Congratulation for a great challenge!

LoRaTracker, can you elaborate on how you configure an SX127x to have it let CRC-check-failing packets be read from the FIFO? Thanks!