In Section 6.5.2, it is said that if the frequency autocorrelation of a channel CHH is flat, then the channel has no time dispersion. It seems we can make a similar statement from (6.54): if h ω is...

In Section 6.5.2, it is said that if the frequency autocorrelation of a channel CHH is flat, then the channel has no time dispersion. It seems we can make a similar statement from (6.54): if h ω is flat, then h(τ) is a delta function, meaning the channel has no time dispersion. Compare these two statements.