It would be interesting to know what simulations have been done to investigate the different possible impacts caused by the propagation itself as well as by man made noise and what the results have been. When I look at the difficult reception of K8K in Germany in FT8 from time to time (polar path with a lot of flutter) even with acceptable signal strenghts I wonder how the signals from Jarvis can be decoded in Germany. But let us see.

Regarding the 10 dB system gain compared to standard fox: Is there somebody in the group who can explain or give me some information how this has been calculated? We can do this off-list because this is somehow quite specific and not so interesting for the majority of the users here.

Despite my above comments/questions: I still believe that the new mode has many advantages when I look at Uwe's list, so this new mode could be another nice step forward. But we should know the trade offs as well.,73 Juergen, DL8LE

Hello Jürgen,
Firstly, this already results from theoretical considerations. Joe answered a similar question on the WSJT GROUP forum as follows:

FT8 transmissions, and each stream of old-style Fox transmissions, each convey a 77-bit payload. Necessarily, when multiple streams are used the 1/N^2 law is in effect and signal strength is reduced.

SuperFox transmissions do not use "streams", and they always convey a payload of 319 bits. For one QSO at a time FT8 is more efficient, and uses much less bandwidth. But for many simultaneous QSOs the SuperFox approach (wider bandwidth, a highly effective Q-ary polar code, 128-FSK constant envelope modulation) wins by a large margin.

Then there have been of course a number of comparative tests (mostly performed by Steve K9AN or Joe). If I remember correctly, the results showed a system gain of between 9.9 and 12.7 dB

73 de DG2YCB,
Uwe