Hello,
Last night I took some more spectra of (b)psk signal and put the results on
my webpage, have a look at :
http://www.qsl.net/on7yd/PSK_TEST/psk_test.htm
Besides the BPSK and PSK signals I also measured a 12WPM CW signal (as
reference) and 3 different 'gradual' PSK signals, one with a gradual phase
shift over 100ms (= 100% of a bitlength), one with a gradual phase shift
over 50ms (= 50% of the bitlength) and one with a gradual phase shift over
25ms (= 25% of the bitlength).
For better understanding I further added the amplitude/time and phase/time
diagrams for each of the signals.
From this measurements it is clear that PSK has the smallest bandwidth,
slighty worse is gradual PSK with 100ms transient time. But gradual PSK
with 50ms transient time has a quite acceptable bandwidth and even gradual
PSk with 25ms transient time is still better than 12WPM CW.
BPSK seems to have all the 'ingredients' needed to fill a significant part
of the band with rubbish.
73, Rik ON7YD
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