https://rfcorner.in/tags/polar-express/Recent content in Polar Express on Dhiru's NotebookHugoenMon, 16 Feb 2026 00:00:00 +0000https://rfcorner.in/posts/the-polar-express/Mon, 16 Feb 2026 00:00:00 +0000https://rfcorner.in/posts/the-polar-express/<h2 id="polar-modulation-for-everyone">Polar Modulation for Everyone</h2> <p>We have been working on SSB generation using <code>polar modulation</code>.</p> <p>Hardware stack: RP2350-Zero MCU board + Fast Si5351 module + AP63301 buck regulator (for 5W mode).</p> <p><img alt="Polar Modulation SSB 1" loading="lazy" src="https://rfcorner.in/images/PolarModulationSSB-Demo-1.png"></p> <p>See <a href="https://github.com/kholia/PolarModulationSSB">https://github.com/kholia/PolarModulationSSB</a> for details.</p> <p>Audio fidelity is acceptable at the moment and should improve further. We still need to hook up the amplitude ("envelope") restoration stage.</p> <h2 id="motivation">Motivation</h2> <p>Why should Guido, Hans, and FlexRadio folks have all the fun? ;)</p>