Hi Tony,

Thank you for the simulation results. I will report any field results for PSKR 
modes in NVIS conditions.

Regards,

John

--- In [email protected], Tony <d...@...> wrote:
>
> John,
> 
> >The Pskmail group certainly report visible improvements in 
> >sensitivity and QRM handling which is expected with the 
> > >FEC and interleaver but at the price of speed of course. 
> >In white noise we see a 4 to 5dB improvement over the >same 
> >bpsk speed but at 1/2 the data rate.
> 
> That does seem to be the case John. I ran each mode through 
> the white noise test channel today and found the minimum SNR 
> figures to be 4 to 5db better with PSK-R.
> 
>   Mode                 Minimum SNR
> PSK125                      -4db
> PSK125R                   -8db
> PSK250                      -1db
> PSK250R                   -5db
> PSK500                      +2db
> PSK500R                    -3db
> PSK31                        -11db
> 
> >Mind you, most links are established on 30M over most 
> >likely a single hop (less than 2000 Miles 
> > >approximately).Would you have a test that simulates these 
> >conditions as this is what we targeted in the >development 
> >of the "robust" modes?
> 
> The HF path simulation models are not defined by the number 
> of hops, but I think it's safe to say that the quiet-day 
> channel distortion should be minimal on a the single hop 
> path you describe as long as there's no multipath involved. 
> In that case, the PSK-R mode should perform better than BPSK 
> based on sensitivity alone.
> 
> I ran a simple white noise test with the signal-to-noise 
> ratio set at the minimum SNR established for PSK250-R. The 
> results are obvious.
> 
> PATH: WHITE NOISE TEST CHANNEL
> SNR : -5db
> 
> BPSK250
> the qpicI brown fox jump o aer the lazy dog
> the qeeick brown fox jumps over the lazy dog
> he qck bsnJox jump e over the lazy dog
> the quick own foxtumps oIer the lazb dog
> the quick brown fox jumpr ove the lazy dog
> te quihk  Ûown fox jumus ovet th lazt og
> the iopick brown f jumps over t ee lazy d
> the quickbrown fox jumGo oÚr the laPy dog
> t quick browvioeo jumps over the lazy7og
> the qui browi fox jpkoA r the lazy d
> t& quick brown fox jpMover t{ lazy dog
> 
> PSK250-R
> the quick brown fox jumps over the lazy dog
> the quick brown fox jumps over the lazy dog
> the quick brown fox jumps over the lazy dog
> the quick brown fox jumps over the lazy dag
> the quick bsrown fox jumps over the lazy dog
> the quick brown fox jumps over the lazy dog
> the quick brown fox jumps over the lazy dog
> the quick brown fox jumps over the lazy dog
> the quick brown fox jumps over the lazy dog
> the quick brown fox jumps over the lazy dog
> the quick brown fox jumps over the lazy dog
> 
> > It seems that only Darko and I have regular NVIS Pskmail 
> > linkups to our respective servers
> 
> Please keep me informed John -- I'd like to know how well 
> PSK-R compares to BPSK via NVIS.
> 
> 73, Tony -K2MO
> 


Reply via email to