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Multiple different carrier frequencies for sensor networks

Open hllhll opened this issue 2 years ago • 7 comments

Is your feature request related to a problem?

I Am trying to analyze a wireless signal from a network of sensors, or, should I say "things". they are using, probably some kind of cheap hardware. The carrier frequency is a little bit off for each of the transmission from the different devices. Thus If I tune demod parameters to a specific burst, it does not match others.

Describe the solution you'd like

URH Already detects the burst automatically, it would be really awesome if it could lock on center frequency of each burst by specifying the number of preamble symbols.

Describe alternatives you've considered

Currently, the only solution for me is to take it off to GNuradio and do some block magic, then Importing the symbols back

Additional context
  • The signal is a 4FSK signal
  • with a relatively narrow bandwidth, so "center spacing" param (I.E. the distance between symbols?) does not allow enough slack for the bit slicer to accept it, the carrier freq is too far off that it decodes invalid bits.

image

hllhll avatar Aug 04 '21 19:08 hllhll

To be honest, I do not think that we can integrate this solution in URH/master. We probably already have the necessary logic blocks in our code but such auto-magic behaviour would break many legacy projects where this behavior is explicitly not wanted. Additionally different center+space settings for different sections (within one signal!) will probably create an UI nightmare...

andynoack avatar Aug 04 '21 22:08 andynoack

So what about an option to enable, disable? (disable by default) UI Can be totally(maybe?) ignored; You already collect a "burst level" information in the form of RSSI; What about attaching the signal mean/lock freq to it?

BTW, I Have this function implemented in GRC, How would one recommend to pipe/plug the graph into URH, While keeping timestamps, RSSI and other metadata useful in GRC?

hllhll avatar Aug 05 '21 09:08 hllhll

Maybe using your custom GRC-flowgraph instead of our default GRC flowgraph (nearly empty) when using the GR backend is a solution for your problem. You could just replace it. What do you think?

andynoack avatar Aug 05 '21 09:08 andynoack

I would like to preserve original rssi, so total demodulation and remodulation might be possible. Im using both grc and urh on windows, any reference on how to use grc as backend? (linux is fine too)

hllhll avatar Aug 15 '21 18:08 hllhll

When GRC is installed, you should be able to select the GR backend in the URH options.

Am 15. August 2021 20:24:14 MESZ schrieb hllhll @.***>:

I would like to preserve original rssi, so total demodulation and remodulation might be possible. Im using both grc and urh on windows, any reference on how to use grc as backend? (linux is fine too)

-- You are receiving this because you commented. Reply to this email directly or view it on GitHub: https://github.com/jopohl/urh/issues/899#issuecomment-899092029 Prof. Dr.-Ing. Andreas Noack Hochschule Stralsund

andynoack avatar Aug 15 '21 18:08 andynoack

image image

I Should open a bug for that? o_O

hllhll avatar Aug 15 '21 18:08 hllhll

Please don't...activate it in the options.

Am 15. August 2021 20:41:44 MESZ schrieb hllhll @.***>:

image image

I Should open a bug for that? o_O

-- You are receiving this because you commented. Reply to this email directly or view it on GitHub: https://github.com/jopohl/urh/issues/899#issuecomment-899093784 Prof. Dr.-Ing. Andreas Noack Hochschule Stralsund

andynoack avatar Aug 15 '21 18:08 andynoack