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wilfrid100
Joined: 27 Nov 2005
Posts: 12
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 19 Jun 2008 6:49 why BPSK matlab coding is diff. than BPSK text book formula |
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im a newbie for digital communication. currently i hav an assignment regarding on BPSK & QPSK matlab. that hav sthgs which im not understanding btw matlab coding and text book formula.
as wat i read in text book, the BPSK transmitted signal is represented as
S_bpsk(t)=m(t)*√(2Eb/Tb)*cos(ωc*t)
but, in matlab coding (an example)
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Ns=100; %vector of length Ns symbols
data=2*round(rand(Ns,1))-1; %this converts 0 into -1, 1 into 1
bpsk=data;
------------------------------------------------------------------------------------
how come the matlab code using a simple -1 & 1 to represent BPSK transmitted signal? (kindly any intelligent can explained this question to me)
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bulx
Joined: 07 Aug 2004
Posts: 163
Helped: 23
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| 20 Jun 2008 12:04 Re: why BPSK matlab coding is diff. than BPSK text book form |
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this ±1 corresponds to just the m(t) in the equation. You have to generate the carrier and mutliply it with your ±1 sequence to get the modulated signal.
-b
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wilfrid100
Joined: 27 Nov 2005
Posts: 12
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| 20 Jun 2008 14:08 why BPSK matlab coding is diff. than BPSK text book formula |
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| OOooo......now i understand, thk you for ur help...
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