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MATLAB RAYLEIGH CHANNEL AND MY CODE GIVE DIFFERENT RESULT

Started by huzaifa March 20, 2008
Hi

I would grately appreciate if someone could ans my question

I have implemented MULTIPATH MODEL( without doppler) and compared it
with MATLAB rayleighchan function.

Every time I see scatterplot of my output it changes shape ( although
overall shape is similar) but MATLAB rayleighchan gives me same 
scatterplot shape.

I dont understand this, we use complex gaussian process scaled by
tap power of each path. Since process is random, I believe my scatterplot
of output cannot be the same! why does matlab show same all the time!
Is there any other algorithm for multipath. I have used tapped delay
model

OR am i doint something wrong in process generation

I have 576 samples in TD.
I generated 576 sample compled gaussian process/sqrt(0.5) to see rayleigh
distribution.
But for each path, I take only 1 sample from these 576 rayleigh process
samples and multiply to 576 TD samples (data). These saples are random
so the phase and magnitude it adds to 576 TD data is also random! Do I
have to normalize all the rayleigh samples by something!

Please answer soon

Huzaifa


On 20 &#2013265932;&#2013265921;&#2013265921;, 07:54, "huzaifa" <hskap...@tataelxsi.co.in> wrote:
> Hi > > I would grately appreciate if someone could ans my question > > I have implemented MULTIPATH MODEL( without doppler) and compared it > with MATLAB rayleighchan function. > > Every time I see scatterplot of my output it changes shape ( although > overall shape is similar) but MATLAB rayleighchan gives me same > scatterplot shape. > > I dont understand this, we use complex gaussian process scaled by > tap power of each path. Since process is random, I believe my scatterplot > of output cannot be the same! why does matlab show same all the time! > Is there any other algorithm for multipath. I have used tapped delay > model > > OR am i doint something wrong in process generation > > I have 576 samples in TD. > I generated 576 sample compled gaussian process/sqrt(0.5) to see rayleigh > distribution. > But for each path, I take only 1 sample from these 576 rayleigh process > samples and multiply to 576 TD samples (data). These saples are random > so the phase and magnitude it adds to 576 TD data is also random! Do I > have to normalize all the rayleigh samples by something! > > Please answer soon > > Huzaifa
I think that MATLAB initiates the channel created by the function rayleighchan with the same values each time. Try typing rayleichan twice in the command menu to see what I mean.
On Apr 2, 4:40&#2013266080;am, frasi...@gmail.com wrote:
> On 20 &#2013265932;&#2013265921;&#2013265921;, 07:54, "huzaifa" <hskap...@tataelxsi.co.in> wrote: > > > > > > > Hi > > > I would grately appreciate if someone could ans my question > > > I have implemented MULTIPATH MODEL( without doppler) and compared it > > with MATLAB rayleighchan function. > > > Every time I see scatterplot of my output it changes shape ( although > > overall shape is similar) but MATLAB rayleighchan gives me same > > scatterplot shape. > > > I dont understand this, we use complex gaussian process scaled by > > tap power of each path. Since process is random, I believe my scatterplot > > of output cannot be the same! why does matlab show same all the time! > > Is there any other algorithm for multipath. I have used tapped delay > > model > > > OR am i doint something wrong in process generation > > > I have 576 samples in TD. > > I generated 576 sample compled gaussian process/sqrt(0.5) to see rayleigh > > distribution. > > But for each path, I take only 1 sample from these 576 rayleigh process > > samples and multiply to 576 TD samples (data). These saples are random > > so the phase and magnitude it adds to 576 TD data is also random! Do I > > have to normalize all the rayleigh samples by something! > > > Please answer soon > > > Huzaifa > > I think that MATLAB initiates the channel created by the function > rayleighchan with the same values each time. Try typing rayleichan > twice in the command menu to see what I mean.- Hide quoted text - > > - Show quoted text -
Could you please tell me, how you used the rayleigh simulink file?? It says you need to use structure. I entered everything correctly but it still doesn't work!! Regards