You can either add the noise directly to the sampled signal and leave the noise bins blank, or you can keep the noise separate as a noise bin type signal.
The noise bins are a simple way to model large bandwidths of noise with a low amount of memory. Upper and lower frequency arrays determine the span of frequencies with average power given by the power array. For example, let’s say UpperFrequency[0] = 191.4 THz and LowerFrequency[0] = 191.3 THz and Power[0] = -40 dBm.
That would mean that there is a noise bin signal from 191.3 THz to 191.4 THz with power -40 dBm. The phase array will give the associated phase at that frequency range as well.