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<p class="MsoNormal">Thank you, Tom.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Here is the video recording: <a href="https://scranton.zoom.us/rec/share/rAJDwTsipnfcwSBQBULQOSyt7l2J-PMhJT4Bkc6cp5aasW2p2myRQKYc6um84A-k.VElZXSB_EiOFf4l3">
https://scranton.zoom.us/rec/share/rAJDwTsipnfcwSBQBULQOSyt7l2J-PMhJT4Bkc6cp5aasW2p2myRQKYc6um84A-k.VElZXSB_EiOFf4l3</a>
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<p class="MsoNormal">73 Nathaniel W2NAF<o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> TangerineSDR <tangerinesdr-bounces@lists.tapr.org>
<b>On Behalf Of </b>Tom McDermott via TangerineSDR<br>
<b>Sent:</b> Monday, December 14, 2020 10:09 PM<br>
<b>To:</b> TAPR TangerineSDR Modular Software Defined Radio <tangerinesdr@lists.tapr.org><br>
<b>Cc:</b> Tom McDermott <tom.n5eg@gmail.com><br>
<b>Subject:</b> [TangerineSDR] Notes from PSWS / TangerineSDR call of 12-14-2020<o:p></o:p></p>
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<p class="MsoNormal">Notes from PSWS / TangerineSDR call of 12-14-2020<o:p></o:p></p>
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<p class="MsoNormal">1. Dan has numerous scripts to install ham radio software on his github for Raspberry Pi and Odroid. <a href="https://github.com/n4xwe">https://github.com/n4xwe</a><o:p></o:p></p>
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<p class="MsoNormal">2. Discussion on chirp decoder algorithms for TangerineSDR. One issue is that some stations do not hold a rigorous schedule, another is that new stations will pop up unexpectedly with (previously) unknown chirp rates and from (previously)
unknown locations. The search space is two or maybe three dimensional. Current solutions for searching for ionosondes are computationally expensive when done on the wideband data.<o:p></o:p></p>
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<p class="MsoNormal">Approaches discussed include:<o:p></o:p></p>
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<p class="MsoNormal">A. Have a few powerful computers that analyze wideband data to search, then farm out the { start time / frequency, chirp rate, location } tuples to multiple TangerineSDRs to locally synchronously dechirp.<o:p></o:p></p>
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<p class="MsoNormal">B. Implement GPU acceleration at some of the receivers to attempt a similar search. Could be done with graphics card, or something like a Jetson Nano, etc.<o:p></o:p></p>
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<p class="MsoNormal">Having the FPGA on the Data Engine dechirp multiple different parallel lower-rate channels (perhaps 8 or 16 per receiver), and/or pre-process a single wideband data stream to reduce the information rate to easily fit on a single gigabit
Ethernet could be helpful to these approaches<o:p></o:p></p>
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<p class="MsoNormal">-- Tom, N5EG<o:p></o:p></p>
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