>The phase distortion that occurs causes havoc with PSK mode reception.
This seems logical.
That's true , but its the same for any single carrier system , to get anywhere near a usable data rate , the speed needs to be high, then comes , inter symbol interference . nothing actually wrong with psk modulation
When its deployed as a multi carrier carrier system , as in the original OFDM data mode MT66 , followed by part installations pactor 3 , Ardop and now, the ROS-VARA , which as in MT63 deploys PSK multi carriers for 'ALL' transfer rates .
when deployed as part of a system , PSK provides excellent disturbed path transmission, though in the test, the traditional ofdm/mmfsk low signal s/n imbalance is demonstrated with MT63, however , revised architecture on the VARA modem , seems to of negated this issue
One question , as why in these now difficult propagation conditions , where modes to only 500 Hz bandwidth compared ?