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<p class="MsoNormal">Thank you, Tom and Scotty!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">73 de Nathaniel W2NAF<o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> hamsci@googlegroups.com <hamsci@googlegroups.com>
<b>On Behalf Of </b>Tom McDermott<br>
<b>Sent:</b> Monday, July 13, 2020 11:21 AM<br>
<b>To:</b> TAPR TangerineSDR Modular Software Defined Radio <tangerinesdr@lists.tapr.org>; hamsci@googlegroups.com<br>
<b>Subject:</b> [HamSCI] White paper on FPGA implementation of chirp receiving (oblique ionosond data)<o:p></o:p></p>
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<p class="MsoNormal">During the HAMSCI call with Juha Viernen we discussed some implementation<o:p></o:p></p>
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<p class="MsoNormal">details of the oblique chirp bases ionosond data. Juha uses 2 x 1 GbE to<o:p></o:p></p>
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<p class="MsoNormal">collect the wideband HF data.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">In reviewing a possible TangerineSDR implementation the de-chirping process<o:p></o:p></p>
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<p class="MsoNormal">seems straight-forward within the data engine FPGA. This approach dramatically<o:p></o:p></p>
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<p class="MsoNormal">reduces the needed datarate from the receiver to the data collection host.<o:p></o:p></p>
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<p class="MsoNormal">One difficulty however could be implementing a spectral whitening filter in front of<o:p></o:p></p>
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<p class="MsoNormal">the de-chirper. <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The attached whitepaper looks at an approach and algorithm that appears<o:p></o:p></p>
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<p class="MsoNormal">to be able to accomplish this within the FPGA itself. Scotty took a quick look at<o:p></o:p></p>
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<p class="MsoNormal">it and believes that it would fit within the currently selected FPGA resources.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Please pass along any comments about this approach. This email has<o:p></o:p></p>
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<p class="MsoNormal">been cross-posted to both HAMSCI and Tangerine lists since it probably is of<o:p></o:p></p>
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<p class="MsoNormal">interest to both.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Dave L.: do we need a new section on the TangerineSDR webpage for white papers?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- Tom, N5EG<o:p></o:p></p>
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<p class="MsoNormal">-- <br>
Please follow the HamSCI Community Participation Guidelines at <a href="http://hamsci.org/hamsci-community-participation-guidelines">
http://hamsci.org/hamsci-community-participation-guidelines</a>.<br>
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