I thought about the same. On pactor, the doppler perturbation is 31/100 of the signalling rate, thus, results less affected, even without taking into account the FEC and QRQ strenghts that Pactor also packs along.
73, Jose, CO2JA Vojtech Bubnik wrote: >> PSK31 failed, bad copy even under good SNR, with 3 ms multipath and > 10 Hz >> Doppler. It did not do well with 2 ms multipath and 1 Hz Doppler. >> >> Since Pactor uses PSK I wondered if it would similarly fail as shown > by the >> PSK31 results. I suspect that it handles Doppler better through > frequency >> tracking algorithms. > > PSK31 bandwidth is much lower than of PSK100 that Pactor 2/3 utilizes. > PSK100 will lock to a signal 100/31 times far mistuned than PSK31. > > Symbol length of PSK31 is 32msec, symbol length of PSK100 is 10msec. I > would say that PSK31 will be oblivious to 2ms multipath, but I suppose > the phase difference of both reflections will not be stable, causing > phase modulation of the summed multipath signal, which PSK100 with > convolutional code will be able to handle. > > 73, Vojtech OK1IAK __________________________________________ Participe en Universidad 2008. 11 al 15 de febrero del 2008. Palacio de las Convenciones, Ciudad de la Habana, Cuba http://www.universidad2008.cu
