"Phil Kane" wrote
IIRC the accepted standard for measuring occupied bandwidth is -26
dB, which includes 99% of the signal.
For regulatory purposes, I think you're probably correct (or close to
correct --- -30dB sticks in my mind). Path engineering types tend to be
more conservative because we actually have to make the circuit work. Since
bandwidth is a constrained resource, communications planners tend to treat
it like money and "make less do more" --- when you're aiming for BER's of
better than 1 x 10 to minus10, your 1% of remaining energy can pretty badly
farkle up an adjacent path.
73, de Hans, K0HB
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