wideband fading
Wideband fading.
Channel under wideband fading is called a frequency selective or dispersive channel.
Under some assumptions,
 \(c(\tau, t)\) is a 2D complex gaussian process, characterized by mean, autocorrelation, and crosscorrelation between I and Q components
 Multipath phases are uniform and independent, so mean is 0 and xcor is 0.
 WSS autocorrelation function defines the channel.

One model that describes this process is the tapped delay line model.