My initial idea is to explore what can be done by processing the audio output from a commercial receiver. There are two things that I want to try:
- Filter the audio signal to improve the reception of SSB, or CW. Of course there will already be some degree of filtering applied in the receiver so improvements may be limited, but at least it will be a start.
- Process the audio signal to receive QRSS signals (slow morse code). Software is already available on Windows to do this, but I want to brew my own.
Following experiments by M0XPD (see his blog) I plan to use an Arduino Due for some of these initial experiments. His results suggest that this is feasible.
I will be using Discrete-Time Signal Processing by Oppenheim and Schafer as a reference.