In the awgn channel the noise added is gaussian as well as white noise...
my question is whether gaussian distributed noises are always white noise....?
is the vice versa is also correct...?
The answer is "NO". Distribution does not concern anything about time or frequency. Gaussion noise can have any power spectrum shape, and the very special one of it is white.
Then how come one can make sure that the noise added is gaussian as well as white noise... suppose i do a awgn simulation in matlab without using the function awgn... randn function will generate gaussian noise but to make sure it is white noise...
when we say that a process is white we just define its second moment,but by knowing that its gaussian some more information will be known such as mean,etc.
and about randn. it produce a white gaussian noise because its samples are uncorrelated and so its white,to produce a colored noise you should use a proper innovation filter which is applied to your white noise and its output will have your desired spectrum charactristics.
actually my problem is to create a verilog model of the awgn channel... for my turbo decoder... so can any one give me idea how to generate this uncorrelated gaussian noise...i think generating this gaussian noise won be a problem... but how to make it uncorrelated so that it is white noise...?
As you see the white noise is independent from the distortion of that random variable.
in other wird you could have a white signal with any distribution.