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GNU Radio

github.com

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Re: GNU Radio

#51

Post by noasaservice »

geenew wrote: post #13
ggm wrote: post #2

Has always done a terrible job of selling itself. A $25 dtv receiver and a chickenwire antenna parabola and code your own satellite TV decoder, learn what radar guns emit, emulate a modem... maybe even shift to IR and do TV controls.. it's, latent in this stuff. But the frontpage doesn't take you there.

Is it possible to use a laptop's built-in wifi antenna / wifi card as the hardware side of a gnu radio setup? That seems like it would be a nice cheap one-two punch for getting started. AFAIR wifi uses the public (unregulated) bands so there should be lots of interesting stuff on those frequencies beyond wifi signals.

> Is it possible to use a laptop's built-in wifi antenna / wifi card as the hardware side of a gnu radio setup?

No. There's a LOT of stuff the wifi chip does to convert EM to data, including despreading and other computationally expensive operations.

Using an expensive SDR, you can follow this paper from 2013 to see the block diagram of what decoding wifi looks like:

https://conferences.sigcomm.org/sigcomm/2013/papers/srif/p9....

Re: GNU Radio

#52

Post by masto »

ggm wrote: post #2

Has always done a terrible job of selling itself. A $25 dtv receiver and a chickenwire antenna parabola and code your own satellite TV decoder, learn what radar guns emit, emulate a modem... maybe even shift to IR and do TV controls.. it's, latent in this stuff. But the frontpage doesn't take you there.

I'm reasonably good at computers, and I even have a small understanding of electronics and radio, but I bought a HackRF One about 6 years ago, and every time I try to use this stuff I get hopelessly lost. Most of the time I can't even get the software running, or figure out which software I need to get running, and when I do I'm hopelessly lost. The only thing I ever managed was to listen to an FM radio station with a program that simplified the interface down to a frequency slider.

I would love to do things like investigate how my water meter broadcasts its readings, but "latent" doesn't even begin to cover how inaccessible this stuff is. There are "tutorials", but they just say "Stick these parts together. There, now you have stuck these parts together!" (https://wiki.gnuradio.org/index.php/Simulation_example:_Narr...)

I know, open source, I should learn everything and then write better documentation.

Re: GNU Radio

#53

Post by colechristensen »

geenew wrote: post #13
ggm wrote: post #2

Has always done a terrible job of selling itself. A $25 dtv receiver and a chickenwire antenna parabola and code your own satellite TV decoder, learn what radar guns emit, emulate a modem... maybe even shift to IR and do TV controls.. it's, latent in this stuff. But the frontpage doesn't take you there.

Is it possible to use a laptop's built-in wifi antenna / wifi card as the hardware side of a gnu radio setup? That seems like it would be a nice cheap one-two punch for getting started. AFAIR wifi uses the public (unregulated) bands so there should be lots of interesting stuff on those frequencies beyond wifi signals.

It has been done because wifi/bluetooth chipsets are mostly software defined radios but the software is in proprietary pretty well locked down firmware environments. The hardware of the radios will also usually be specified for very specific bands and will have less general purpose uses.

Also note that it’s easy to break FCC regulations and generally be disruptive if you mess around with this stuff and don’t know what you’re doing, and the FCC happily hands out five digit fines.

https://github.com/seemoo-lab/mobisys2018_nexmon_software_de...

Re: GNU Radio

#54

Post by BenjiWiebe »

superkuh wrote: post #21
ggm wrote: post #2

Has always done a terrible job of selling itself. A $25 dtv receiver and a chickenwire antenna parabola and code your own satellite TV decoder, learn what radar guns emit, emulate a modem... maybe even shift to IR and do TV controls.. it's, latent in this stuff. But the frontpage doesn't take you there.

Sure. That's because GNU Radio is for making the applications/flowgraphs. It is not an application you "use". It is an application for making applications. Give a newbie even the friendly GUI gnuradio-companion and they're not going to be able to do much without some serious time learning or existing DSP background.

Right. There isn't any way of making it easy or beginner friendly, because DSP and RF aren't simple topics.

Re: GNU Radio

#55

Post by BenjiWiebe »

doom2 wrote: post #28

Does GNU Radio have any utility for amateur radio operators? For example, tx/rx of FT8 or PSK31 (or any other digital modes)?

Yes, but why not use the existing software? Building flowgraphs in GNU Radio is not simple.

Re: GNU Radio

#57

Post by MrQuincle »

masto wrote: post #52
ggm wrote: post #2

Has always done a terrible job of selling itself. A $25 dtv receiver and a chickenwire antenna parabola and code your own satellite TV decoder, learn what radar guns emit, emulate a modem... maybe even shift to IR and do TV controls.. it's, latent in this stuff. But the frontpage doesn't take you there.

I'm reasonably good at computers, and I even have a small understanding of electronics and radio, but I bought a HackRF One about 6 years ago, and every time I try to use this stuff I get hopelessly lost. Most of the time I can't even get the software running, or figure out which software I need to get running, and when I do I'm hopelessly lost. The only thing I ever managed was to listen to an FM radio station with…

I reverse engineered a so called social alarm a bit ago. You can find it here: https://github.com/mrquincle/social_alarm

Gnuradio was also new to me. However with two HackRFs I could do the entire thing. First replay attacks. Then trying to get the code by building up a set of processing blocks. Last synthesis of the complete signal.

Very nice to do! Felt great!

Re: GNU Radio

#58

Post by jancsika »

masto wrote: post #52
ggm wrote: post #2

Has always done a terrible job of selling itself. A $25 dtv receiver and a chickenwire antenna parabola and code your own satellite TV decoder, learn what radar guns emit, emulate a modem... maybe even shift to IR and do TV controls.. it's, latent in this stuff. But the frontpage doesn't take you there.

I'm reasonably good at computers, and I even have a small understanding of electronics and radio, but I bought a HackRF One about 6 years ago, and every time I try to use this stuff I get hopelessly lost. Most of the time I can't even get the software running, or figure out which software I need to get running, and when I do I'm hopelessly lost. The only thing I ever managed was to listen to an FM radio station with…

You should consider this a real treat-- it's like you're getting to travel back to the 90s open source scene for free.

-Tom Sawyer

Re: GNU Radio

#59

Post by Shared404 »

throway453sde wrote: post #27
RF_Savage wrote: post #15

Earlier quoted context omitted.

Due to it being a radio licenced by rule, the firmware in wifi devices is locked down tight. If it ware wide open FCC would revoke it's type acceptance. The only project that so far has managed to even partially use wifi hardware as a more generic SDR is nexmon[1] and even that is rather involved. Really cool project but not much heard since 2018. For just experimenting with modems across a noisy path one could just…

If i run linux can i modify the firmware? Also the regulations differ from country to country so this should be legal in some of the country.

Firmware is typically loaded directly onto the hardware, so you would have to have a way to flash your custom firmware to the wifi antenna/card.

In the US and other countries, it is to the best of my knowledge legal to modify firmware for hardware you own. The illegal part is broadcasting, most bandwidths are highly regulated. Listening on the other hand is mostly legal, or at the very least extremely likely to fly under the radar.

Re: GNU Radio

#60

Post by RF_Savage »

throway453sde wrote: post #27
RF_Savage wrote: post #15

Earlier quoted context omitted.

Due to it being a radio licenced by rule, the firmware in wifi devices is locked down tight. If it ware wide open FCC would revoke it's type acceptance. The only project that so far has managed to even partially use wifi hardware as a more generic SDR is nexmon[1] and even that is rather involved. Really cool project but not much heard since 2018. For just experimenting with modems across a noisy path one could just…

If i run linux can i modify the firmware? Also the regulations differ from country to country so this should be legal in some of the country.

You will not be able to modify the firmware blob just by running linux.

Few years back there was danger of FCC de facto banning alternative router firmwares like openwrt to prevent tampering with the wifi cards firmware.

This was the "only manufacturer signed firmware allowed" thing that thankfully was avoided.

FCC's motivation in this is to prevent people from using too much power or certain frequencies.

And as most manufacturers want to be able to sell in USA, it would have likely affected all versions. Kainda like how many wifi devices sold in Europe only go up to channel 11 on 2.4GHz, when the EU band goes up to channel 13. But ch12 and ch13 are not legal in usa, so they are blocked.

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