
An open source Global Navigation Satellite Systems software-defined receiver - okket
https://gnss-sdr.org/
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skykooler
I wonder if this would be usable for applications like high-altitude balloon
tracking, where commercial GPS receivers cut out above 18km due to ITAR
regulations.

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unsignedint
Looks like that limitation is removed.[0]

[0]:
[https://www.gps.gov/cgsic/meetings/2014/kim.pdf](https://www.gps.gov/cgsic/meetings/2014/kim.pdf)
(page 7)

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hahnpv
Limitation is to commercial sales of receivers. Private individuals
building/operating their own receivers have no limits.

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planteen
Does anyone know if any of these SDR solutions for hobbyists can get survey
grade position solutions?

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lucb1e
We've been trying to use it with a hackrf and bladerf and no dice at receiving
actual GPS, even with an antenna exactly tuned to 1.57542GHz. Only when we
transmit GPS signals ourselves so the signal is much stronger, are we able to
obtain any satellites at all.

The software works, but you need a low noise amplifier or something else that
you'd probably have to order from America or China (that would have taken too
long for our school project).

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UncleEntity
I was under the impression that gps antennas were powered...and special.

The receiver has to pull the signal from below the noise floor so needs a
little help but, admittedly, my understanding on how it all works is limited.

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tonyarkles
A sibling comment mentioned using a Bias-T, and that's pretty much always
needed unless you're using a COTS Rx (which would generally have one built-in)

It doesn't even have to be a fancy one. In a pinch, once, I use a random-
valued inductor and the smallest-valued capacitor I had on-hand, and soldered
them to a little PCB I made by slicing up copper-clad board with an x-acto
knife. (0603 parts, if I recall.) Worked like a charm!

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jesuslop
What sat-constellation does this hear?

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msl
It appears that the eventual objective is to be able to use any GNSS. The page
on telemetry decoder blocks[1] seems to indicate that GPS, GLONASS and Galileo
signals are currently supported.

[1] [https://gnss-sdr.org/docs/sp-blocks/telemetry-decoder/](https://gnss-
sdr.org/docs/sp-blocks/telemetry-decoder/)

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CamperBob2
_At this time of writing, GNSS-SDR cannot be built natively on Microsoft
Windows. As far as authors’ knowledge, nothing prevents it but their own
ignorance on Microsoft’s building tools. Users have reported successful
buildings of GNU Radio on Windows systems, so there should be not serious
caveats building GNSS-SDR as well. However, GNSS-SDR is not blocked for
Windows users. There are several virtualization tools that work well._

Great, let's blow off 95% of the desktop market and see how that goes for us.

Doesn't GNU Radio already support GNSS decoders? If I want a GPL-encumbered
GNSS receiver solution, there are plenty of existing options.

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knorker
The entitlement is strong in this one...

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CamperBob2
Yes, that's certainly an easy conclusion to draw, isn't it.

