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Author Topic: Raspberry Pi, antennas, and SDR  (Read 7415 times)

Offline IQ_imbalance

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Raspberry Pi, antennas, and SDR
« on: February 14, 2013, 0231 UTC »
So now that you can pretty much have a complete computer for $35 or so, and add on a SDR for another $15....thoughts on how this might be fun?  Since you could have a $50 receiver right at your antenna, would it be easier to build arrays since you wouldn't have to worry about losses in the feed (just about running the ethernet cables between the boxes...)?
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Offline IQ_imbalance

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Re: Raspberry Pi, antennas, and SDR
« Reply #1 on: February 23, 2013, 1830 UTC »
Years of research in dusty library stacks and damp basements has revealed this:

http://k1gto.blogspot.com/2012/09/compiling-gnuradio-on-raspberry-pi-raspi.html

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Offline corq

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Re: Raspberry Pi, antennas, and SDR
« Reply #2 on: May 07, 2013, 1020 UTC »
So,  I successfully have the server script for QtRadio from the ghpsdr3-alex project functional  on the Pi. HOWEVER... It chokes on sending the audio at least from the sdriq, because of the streaming bit rate and IQ data CPU constraints. It works, but the audio is choppy and unlistenable.

Tonight I tested compiling the gqrx software on the laptop and may try to get it going on the Pi over the next several days with the rtlsdr dongle. That dongle won't do HF, but as a proof of concept I just want to see it work, and possibly move up to a beagleboard black (45 bucks) to try the sdriq qtradio again with a slightly beefier CPU.

Will try to post here any of my successes or defeats ;)

Update 1:

BeagleBone Black compiles/installs QtSDR/GHPSDR3-Alex just fine, but the SQR-IQ streams (at present) at a bit rate that seems still a bit too high for the 1ghz cpu to process optimally. Every thing works, but again, the audio is halted and choppy, Same as the Raspberry Pi. I think it's more to do with the audio drivers and processing for the SDR-IQ, and maybe there are further compiling options I need to check into, but out of the box the resources demanded upon the ARM processor is a bit too much. 

I'm giving linrad an install and seeing if there's anything to be done with that and the SDR-IQ, being that linrad is console-based, much lower resources overhead.





 
« Last Edit: May 13, 2013, 0429 UTC by corq »
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