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I have received similar requests from a few others. We should probably

address this perceived need before too long. I would like to retire

WSPR-X, anyway, and do further development within WSJT-X.

 

I am not persuaded that WSPR-15 is really the best way to go. Here are

some potentially important questions:

 

1. Is it clear that in practice WSPR-15 provides LF/MF decodes at lower

S/N than WSPR-2? If so, ho much lower?

 

2. Could an equivalent gain in performance be achieved by having the

decoder average several consecutive, properly synchronized WSPR-2

transmissions?

 

3. If a more sensitive WSPR-like mode is truly needed for LF/MF

experimentation, would it be better to create something that for now

I'll call "WSPR-MSK", which (like MSK144) uses OQPSK (Offset Quadrature

Phase-Shift Keying), a constant-envelope waveform, coherent

demodulation, and an LDPC code? Steve (K9AN) and I have discussed such

a possible mode, and we might be more motivated to develop that rather

than going "back" to WSPR-15. I suspect WSPR-MSK could be made as

sensitive (or better) than WSPR-15, even with transmissions shorter than

15 minutes.

 

-- 73, Joe, K1JT