fast and slow Rayleigh fading channel

[k2121]

Can any one tell me what is the difference between fast and slow Rayleigh fading channel?
And how can I represent them be MATLAB?

Thanks in advance

 

[Sherra]

Fast fading occurs when the coherence time of the channel is small relative to the delay constraint of the channel
The difference is relative, but this generally means variations in amplitude that change slowly/fast with time. E.g slowly compared to the transmission frame length.

Often engineers think of slow fading as being fading where the system might have time to react in some way whereas Fast fading is signal variation that is considered too rapid for the system to follow.

Hope i helped clear that for you!

 

[k2121]

Thanks a lot

 

[k2121]

We represent the channel gain and the noise in Rayleigh fading channel by MATLAB as follows.
h=1/square(0.5)*(round(rand(1,k))+j*round(rand(1,k))) channel gain, k: number of bits

n=1/square(0.5)*(round(rand(1,k))+j*round(rand(1,k))) additive noise
What is square(0.5) in h and n and what is their effect on the signal?

Thanks in advance

 

[Sherra]

I think it is divided by sqrt(2) for normalization.
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