[Lf] [Fwd: LF: (b)psk signal bandwidths]

[Andre' Kesteloot]

Rik Strobbe wrote:

> 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