raja.cedt wrote on Nov 8th, 2011, 5:58am:hello buddypoor,
what is the meaning of -ve group delay?
Thanks,
raj.
Hi Raj,
as you know - group delay is defined as the negative slope of the phase-vs-frequency response.
That means: If you have a system with a positive slope of this kind the resulting group delay is negative (and also the group velocity).
What does it mean? According to its definition the information (e.g. envelope of an AM signal) is available at the output before it appears at the input. Sounds surprising - but it is the truth and has been prooved by several experiments.