Here you will find information about Laser Communications DX Experimentation.

Refresh/Reload this and other pages to get the latest changes.

NOTE: Looking into a Laser (even a Laser pointer) is dangerous to your eyesight if intentional and unfortunately just as dangerous if accidental.  A laser of any power level is like a loaded gun with the safety catch off.  Be always aware where is it pointing at all times!!!

My main interest is in DSP techniques especially narrowband modes and that will be the focus of these pages.  For other information see Laser Links at the left.

In particular I am interested in the characteristics of optical scatter modes (see Technical Topics) such as forward, backward scatter and cloudbounce.

Make sure you visit Technical Topics for information on equipment, techniques, hardware and software.  Technical Topics also contains a link to my Experimentation Notebook and some Data Sheets.

Also contained in Technical Topics is information on the two narrowband modes I will be experimenting with:- Absolute Frequency Keying (AFK) and Frequency Difference Keying (FDK).  I have already written software for and used FDK on the LF bands (AXSO experimental station on 177.5kHz) which showed that FDK has a S/N advantage of about 17dB over PSK31 (as you would expect as the data rate is much slower).   Laser Comms DX allows the use of the earlier mode I was experimenting with (AFK) because of the easier frequency accuracy/stability requirements.

Also I intend to experiment with another variation on AFK I call Incremental Frequency Keying (IFK) which will attempt to combine the advantages of AFK and FDK. Details of IFK can be also found in Technical Topics.

You might call me the Alphabet Soup Experimenter!!!

Have a look at "What is Experimentation".  This little piece is sure to light a few fuses, but don't bother to tackle me over the opinions expressed there as I am bigoted and narrow-minded and so you would be wasting your time :-)

Use the navigation links on the left to have a look around.   E-mail me with comments, suggestions and corrections.