reg. AWGN and rayleigh fading channel noises, if u are to simulate using matlab,
then,
AWGN is an additive noise, u would know. generate a signal x say of length 1000,
then the corrupted signal with AWGN is,
y = x + randn(1,1000) ; where 1,1000 will generate gaussian noise with 1 row and 1000 values.
reg. rayleigh noise, its multiplicative in general as opposed to the AWGN, so generate this noise and just multiply instead of adding. in general, for a communication system, channel is rayleigh and in addition to that, thermal noise exists.. so u have to multiply and add..
rayleegh fading noise...
y = x * randn(1,0000);
comm system,
y = x * randn(1,1000) + randn(1,1000);
incase, i misunderstood ur question/ u need something other than this, pls reply this post!
/cedance