Undefined function 'mtimes' for input arguments of type 'cell'.?

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sharif shikder
sharif shikder 2016-1-23
回答： eslam saad 2018-10-16
%clear all;
%close all;
L_0=10; %Average outer scale of turbulance in m.
c_n=5*10^-12; %Structure constant of refractive index in m^-2/3.
c=3*10^8; % Speed of light in m/s.
f=30*10^9; % Frequency in HZ.
lamda=c/f;
L=4000;
del_ky=0.01;
[EbN0_dB]=[10 15 20 25 30 35 40 45 50 55];
sigma=[{0.307*(c_n)^2}*{(2*3.1416/lamda)^1.17}*{L^(1.833)}]-[{0.742*(c_n)^2}*{(2*23.1416/lamda)^0.17}*{(L^2.833)*(L_0^2)}]
for i= 1:10
snr=10.^(EbN0_dB(i)/10);
ky=0:del_ky:10;
pe=1/2.*erfc(ky.*sqrt(snr/2));
pdf_ky=(1/(sqrt(2*3.1416)*sigma))*exp((-ky.^2)/2*sigma^2);
prod=pe.*pdf_ky;
ber(i)=trapz(prod)*del_ky;
end
CDF_ky=trapz(pdf_ky)*del_ky
ber=ber./CDF_ky;
semilogy(EbN0_dB,ber)
ylabel('Bit Error Rate(BER)')
xlabel('Signal to Noise Ratio(SNR)');

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采纳的回答

jgg
jgg 2016-1-23
编辑：jgg 2016-1-23
This expression:
sigma=[{0.307*(c_n)^2}*{(2*3.1416/lamda)^1.17}*{L^(1.833)}]-[{0.742*(c_n)^2}*{(2*23.1416/lamda)^0.17}*{(L^2.833)*(L_0^2)}]
is not proper Matlab syntax. The {} brackers denote cells. You cannot use them as delimiters for order of operations. The same is true of [] which have particular meaning. You probably want this instead:
sigma=((0.307*(c_n)^2)*((2*3.1416/lamda)^1.17)*(L^(1.833)))-((0.742*(c_n)^2)*((2*23.1416/lamda)^0.17)*((L^2.833)*(L_0^2)))
However, I strongly advise you to read up on the basic syntax of the language you're using. This is a really fundamental mistake, and if you don't understand this you'll run into error after error. You wouldn't try and program in Java or C++ by guessing at what the different commands mean, so why would you code in Matlab without looking up how to write expressions?
Try this getting started link before coding any further.
  1 个评论
Walter Roberson
Walter Roberson 2016-1-23
Oh, you would be astonished how many people program C++ by guessing at what the different commands mean. 15 years ago, the documentation for the C++ Standard Library was already effectively too big to read, so people mostly don't read it.

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eslam saad
eslam saad 2018-10-16
i need power this matrix [0.3] [0.3] [0.2] [0.2] [0.2] [0.5] [0.2] [0.1] [0.1] [0.2] [0.6] [0.1]

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