# Recent content by nightmaresc

1. ### Relationship between Group Velocity and Group Delay | Phase Velocity and Phase Delay

I am getting confused between the concept of group velocity vs. group delay and phase delay vs. phase velocity. Lets assume that some channel has same group velocity and phase velocity then does this mean that group delay and phase delay are same for that channel? Thanks in advance.
2. ### Deriving Phase response from Group Delay

Thank you for the insight. Is there any other way to determine phase response given group delay? Another question I have is that for a filter that gives non linear phase response phase delay and group delay are generally different while for linear phase response group delay and phase delay are...
3. ### Deriving Phase response from Group Delay

Hi, Assume I have a constant group delay of 1 second for all frequencies then I can determine the phase response to be: phase(f)=C - 2*pi* $\int$tau df where tau is the delay of 1 second. How do I determine the constant C which is the phase response at zero frequency?
4. ### Question about Parabolic Phase (Linear Time-Delay) Filter for Ionospheric channel

The equation for this filter according to this book "Simulation of Communication Systems" by Kluwer is defined as H(f)=exp(j*$\theta$*$\omega$^2) where $\omega$=2*pi*f and $\theta$ is "the phase at a reference frequency of $\omega$=1rad/s". What does "the phase at a reference...