Hi Patrick, Are you thinking about incorporate J65A in Multipsk? It would be great
LA5VNA Steinar Patrick Lindecker wrote: > > Hello to all, > > _Comparizon with S/N Multipsk figures._ > > According to JT65 specifications, this mode decodes with few errors > down to -23 dB, with a normalized band of 2.5 KHz. > All Multipsk figures are normalized with a band of 3 KHz. -23 dB in > 2.5 KHz is about -24 dB in 3 KHz band (-23.792 dB exactly). > > This figure of -24 dB can be compared to Olivia 250-8 which has a > minimum S/N of -14 dB. So JT65 is 10 dB better or 10 times better. > But of course JT65 is much slower that Olivia 250-8. > > The only modes which are close to JT65 are: > * THROBX: Lowest S/N: -18,5 dB for the 1 baud, -17.5 dB for the 2 bauds > * PSKAM10: Lowest S/N : -19.5 dB > > In conclusion JT65 is better (under S/N criteria) that any modes in > Multipsk. > > 73 > Patrick > > > > > > ----- Original Message ----- > *From:* Tony <mailto:[EMAIL PROTECTED]> > *To:* digitalradio@yahoogroups.com > <mailto:digitalradio@yahoogroups.com> > *Sent:* Saturday, April 21, 2007 9:25 AM > *Subject:* [digitalradio] Path Simulator tests -- JT65A vs Olivia > and others > > All: > > I used Pathsim to compare the sensitivity of JT65A > vs MFSK, PSK31 and OLIVIA using AWGN to alter the > SNR. I ran direct-path with no ionospheric > disturbance. > > The chat modes decoded with error-free print down > to -12 to -14db SNR. The JT65A mode decoded > at -27db SNR (signal inaudible). > > Assuming the Pathsim white noise measurments were > accurate, I think it's safte to say that JT65 is > capable of decoding much weaker signals than the > others. Would be interesting to see how it does > with simulated ionospheric disturbances. > > 73 Tony - KT2Q > >
