Hüllkurvenausgang für EER

Software von Pavel Demin, HPSDR für den Red Pitaya
Beiträge: 16
Registriert: Sa Apr 08, 2017 7:51 pm

Hüllkurvenausgang für EER

Beitrag von XQ6FOD » Sa Apr 08, 2017 10:26 pm

A question/request for Pavel:

Would it be possible to add an envelope output to the RP software, for those of us who would like to experiment with EER?

In the Hermes such an output is provided as a pulse-width-modulated 200kHz digital signal. Actually I think that directly providing the analog envelope signal is far more flexible than that, and the RP lends itself perfectly to it, given its two RF outputs! So, all that would be needed is to take the envelope data provided by PowerSDR in the EER mode, and send it to the OUT2 port of the RP.

Of course an envelope signal could be produced in hardware, using a simple (but hopefully linear!) amplitude detector connected to OUT1. But in this case there is no DSP-controlled delay to compensate for the power supply's low pass filter's delay! It's much better to use a mathematically generated envelope signal with adjustable delay, as implemented in PowerSDR. An additional benefit is that nonlinar loading of OUT1 by the RF amplifier wouldn't distort the envelope signal on OUT2!

If you could implement this, Pavel, you would make this old tinkerer down in Chile very happy!

Manfred, XQ6FOD