BPSK BER with OFDM modulation

Hello! Kirishna ur matlab script is very help full to simulate an OFDM over AWGN channel using BPSK and also other modulation scheme.Can u forward me a matlab script that can be used to simulate performance of BPSK modulated OFDM with a combination of TCM(Trellis coded Modulation)over a fading channel.
Hope fully u will

dear , thank you very much
can i use not rand binary data in line 9 in the script
i mean i have data positive and negative and want to put it instead of binary random data ,
so please i want your help in solving this problem , because i try to put this data but failed to run .
regards
traiq

hi, KRISHNA
can u explain me the main difference of simulation results between the BPSK and BPSK with OFDM.What are the main factors that will effect the BER,and in which of the two two systems the BER performance is good,please help me as soon as possible because my project submission last date is 30th Sep., and what are the referances i have to read to understand this project.I hopefully waiting for your response,thank you

[...] BPSK BER with OFDM modulation [...]

Hello! Krishna
Thank you! for ur help . But now i have got a problem when i wrote a matlab code to simulate the BER performance of a trellis coded OFDM ( OFDM with trellis coded Modulation) and i can’t get a proper result . Please try to help me by sending a Matlab code to simulate OFDM with TCM.
Thank you in advance
Lealem

Hi Krishna

thank you very much for Your simulation and theory prgram, really they are very useful. Do you have the matlab code for OFDM with 16-QAM in AWGN and Rayleigh Channels.
Best Regards
Hussien

Hi Krishna
One more thing: I’m looking for MATLAB code for channel estimation and synchronization for OFDM system.

Hi Krishna,
Thank you very much for your matlab script. I’m trying BER for OFDM using 16QAM, but I dont know what is Wrong in my code?! here is my code:
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% BER for OFDM using 16QAM Modulation
clear all
close all;
clc;
M = 16; % number of QAM constellation points (4,16,64,256)
nFFT = 64; % fft size
nDSC = 52; % number of data subcarriers
Td = 64; % Data Symbol Duration
Tcp = 16; % cylic prefix Duration (GI=1/4)
nBitPerSym = 52; % number of bits per OFDM symbol (same as the number of subcarriers for BPSK)
nSym = 10^4; % number of symbols
k = log2(M); % bits per symbol
EbN0dB = [0:16]; % bit to noise ratio
EsN0dB = EbN0dB + 10*log10(nDSC/nFFT) + 10*log10(64/80)+ 10*log10(k); % converting to EsNo (EsN0 = EbN0*(nDSC/nFFT)*(Td/(Td+Tcp))
% OFDM
for ii = 1:length(EbN0dB)
% Transmitter
%data Generation
ipBit = randint(1,nBitPerSym*nSym,M);
%Data Modulation
ipMod = (1/sqrt(10))*qammod(ipBit,M); % 16QAM modulation
tx = ipMod;
% S/P
ipMod = reshape(ipMod,nBitPerSym,nSym).’; % grouping into multiple symbolsa
% Assigning modulated symbols to subcarriers from [-26 to -1, +1 to +26] (zeros padding)
xF = [zeros(nSym,6) ipMod(:,[1:nBitPerSym/2]) zeros(nSym,1) ipMod(:,[nBitPerSym/2+1:nBitPerSym]) zeros(nSym,5)] ;
% Taking IFFT, the term (nFFT/sqrt(nDSC)) is for normalizing the power of transmit symbol to 1
xt = (nFFT/sqrt(nDSC))*ifft(fftshift(xF.’)).’;
% Appending cylic prefix
xt = [xt(:,[49:64]) xt];
% P/S
xt = reshape(xt.’,1,nSym*80);
% Generation Gaussian noise of unit variance, 0 mean
nt = 1/sqrt(2)*[randn(1,nSym*80) + j*randn(1,nSym*80)];
% Adding noise, the term sqrt(80/64) is to account for the wasted energy due to cyclic prefix
yt = sqrt(80/64)*xt + 10^(-EsN0dB(ii)/20)*nt;
yts = sqrt(80/64)*xt + 10^(-EsN0dB(ii)/20)*nt;
% Receiver
% S/P
yt = reshape(yt.’,80,nSym).’;
% removing cyclic prefix
yt = yt(:,[17:80]);
% Taking FFT (converting to frequency domain)
yF = (sqrt(nDSC)/nFFT)*fftshift(fft(yt.’)).’;
% zero removal
yMod = yF(:,[6+[1:nBitPerSym/2] 7+[nBitPerSym/2+1:nBitPerSym] ]);
rx = reshape(yMod,1,520000);
% 16QAM Demodulation
ipBitHat = qamdemod(yMod*sqrt(10),M); % rxData =qamdemod(rxDataMod*sqrt(10),M);
% P/S
ipBitHat = reshape(ipBitHat.’,nBitPerSym*nSym,1).’;
% counting the errors
nErr(ii) = size(find(ipBit - ipBitHat),2);
end
simBer = nErr/(nSym*nBitPerSym);
theoryBer = (1/k)*3/2*erfc(sqrt(k*0.1*(10.^(EbN0dB/10))));
figure (1)
semilogy(EbN0dB,theoryBer,’ms-’,'LineWidth’,2,’MarkerSize’,5);
hold on
semilogy(EbN0dB,simBer,’bx-’,'LineWidth’,2,’MarkerSize’,5);
axis([0 16 10^-5 1]);
grid on
legend(’theory’, ’simulation’);
xlabel(’Eb/No, dB’)
ylabel(’Bit Error Rate’)
title(’Bit error probability curve for 16QAM using OFDM’)
hold off
%####################
Regards
Moayid

thank’s…can it made using another methode?except matlab.haw about C++.

Hi,
I saw your code for OFDM transmitter. You have written the code assuming that the bits are coming at the rate of 20Mbps. Is there a way to write a MATLAB script that will simulate a random bit generator at 20MHz using RAND function or should we only go to simulink for that? I would like to see the spectrum of the OFDM symbols for an random input of 20MHZ. though we can plot the spectrum by taking the x-axis as Fs*(-N/2:1:N/2)/N, it would only be to visulaise the plot.
Can you give me a hint on that?
Thank you.
Bye.

hi krishna
i am trying to simulate ofdm with bpsk.i was able to get the +1 -1 signs.what do i need to do before applying this out put to IFFT.
thanks for your help before hand

i am using ifft size 64,for 52 subcarriers