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On Feb 3, 9:29 pm, Idin Motedayen-Aval
<run.signat...@MATLAB.for.email> wrote:
> Ishwinder Singh wrote:
> > Hi Kiran,
>
> > I am facing exactly the same problem as you mentioned. My encoding-decoding
> > (Convolutional encoder-Viterbi decoder) set works fine with AWGN but the
> > moment i subject it to Rayleigh fading, it doesn't show any gain with
> > respect to the uncoded data.
>
> > For Rayleigh fading, i am using Rayleighchan() function in the Matlab's
> > Communications blockset.
>
> > Request Mathworks for any leads in this regard.
>
> > Regards
> > Ishwinder
>
> Ishwinder & Kiran,
> My guess is that you are not correcting the phase rotation introduced by
> the Rayleighchannel. The file referred to by Kiran does this on line
> 34 (yHat = y./h;). Since thechannelstate (h) is assumed to be
> perfectly known to the receiver, we can simply do the above operation.
> You can see my models also:http://www.mathworks.com/matlabcentral/fileexchange/22316-communicati...
> (Check out the Rayleigh Fading models)
> These also assume perfectchannelstate information (CSI) at the
> receiver. Mind you, both files also assume flat fading. Multipath
> fading (frequency selective) will be more complicated to deal with and
> correct.
>
> If thechannelis unknown at the receiver, you will need to dochannelestimation, etc. (i.e. more advanced equalization). There are demos in
> the Communications Blockset that show equalization.
>
> HTH,
> Idin
>
>
>
>
>
> > "kiran " <kirankumar...@gmail.com> wrote in message
> > <hiomt7$1b...@fred.mathworks.com>...
> >> Hi frds.,
>
> >> I am designing one CDMA system. In that i have to use rayleigh fading
> >>channel. When I referred to some other previouschanneldesign they
> >> are working for normal txdata (randomly generated data no data
> >> processing on Tx'ed data).
>
> >>http://www.mathworks.com/matlabcentral/fileexchange/21058-ber-for-bps...
>
> >> But in my program I am doing encoding(using convolution encoder) the
> >> tx'ed data bits and spreading (PN sequence) and both are perferctly
> >> working.
> >> When I am used preivous rayleigh fadingchannelits not working for
> >> coding or spreading or for both.
> >> Could any body give me any reference or any matlab code that help me.
> >> I need simple rayleigh fadingchannel(not like doppler shift no
> >> delay) just for now single path rayleigh fading I need.
>
> >> Thank you in advance.
>
> --
> Idin Motedayen-Aval
> The MathWorks, Inc.
> zq=[4 2 5 -15 -1 -3 24 -57 45 -12 19 -12 15 -8 3 -7 8 -69 53 12 -2];
> char(filter(1,[1,-1],[105 zq])), clear zq
hi i am doing the same and i have same problem!
i am doing my master thesis on LTE.i am trying to implement mmse and
svd estimation but i have some probleme
this is my mmse code,could some how help me?it doesn't work.
i have my pdp and its length is L.
SNR = 1/(noiseVar);
beta=1;
power_delay_profile=[power_delay_profile zeros(1,fftlen-(L))];
power_delay_profile=fft(power_delay_profile);
power_delay_profile=diag(power_delay_profile(carriers));
% Calculate frequency correlation matrix
R_hh =power_delay_profile;
R_hy = R_hh + (((beta/SNR)* eye(length(carriers))));
% Calculate LMMSE estimate
h_LMMSE = (R_hh*inv(R_hy)) * h_LS;
please help!
this is the paper i refer
http://www.sps.ele.tue.nl/members/C.K.Ho/paper/Robust%20MMSE%20channe...
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