This started out as a project to automatically gather reception records of digimode activity and then make those records available in near realtime to interested parties — typically the amateur who initiated the communication. The way that it works is that many amateurs will run a client that will monitor received traffic for callsigns (the pattern 'de callsign callsign') and, when seen, will report this fact. This is of interest to the amateur who transmitted adn they will be able to see where their signal was received. The pattern chosen is typically part of a standard CQ call. The duplicate check is to make sure that the callsign is not corrupted. The rules for protocols like FT8 are different as the callsigns are protected by error correction. You do still need to call CQ in order for your signal to be reported.
The way that this would be used is that an amateur would call CQ and could then (within a few minutes) see where his signal was received. This can be useful in determining propagation conditions or in adjusting antenna and/or radio parameters. It will also provide an archive of reception records that can be used for research purposes.
There is a map display of this information.
There also a page of statistics about the project.
If this is interesting to you, then please contact me at the email address below to see if there is a client for your digital mode decoding application, or you can contact the author of your package directly, and point him at this page.
Note: This system does not transmit any signals over the air, it just makes use of existing signals that are being transmitted by people calling CQ. This approach is different to some other propagation reporting tools, and has the advantage that adding more monitoring stations provides better coverage without consuming any bandwidth. Also, you don't need to have an amateur radio license to participate. All that is needed is an antenna, a radio and a computer, and you can start monitoring. You will need to pick a 'callsign' to send in reports under — pick something with your country prefix on it, such as W/SWL/BOSTON for US, shortwave listener in Boston.