i got this error : ??? Subscripted assignment dimension mismatch. Error in ==> crmapping at 6 iout(2:27,:)=idata(1:26,:); Error in ==> OFDMA512 at 36 [iout,qout] = crmapping(y,ylen,fftlength,nd);

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ahmed on 22 Jun 2013

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https://www.mathworks.com/matlabcentral/answers/79924-i-got-this-error-subscripted-assignment-dimension-mismatch-error-in-crmapping-at-6-iou

%/////////OFDMA///////////

clear all;close all;clc; %,,,,,,,,,,,,,System Parameters,,,,,,,,,,,,

fftlength = 512; nd = 6; BW = 5e6; FS = 2*BW; % Sampling Frequency % No. of Subcarriers NS = 512;

%,,,,,,,,,,,,,,,,,main program,,,,,,,,,,,,,,,,

% Input Generation x = rand(1,NS)>0.5; % Conversion of data from serial to parallel p = series2parallel(x,NS); % M ary Modulation of PSK and QAM M = 2; X = 0; for count1 = 2:1:7; if (M==2||M==4||M==16||M==64) M = M+X % M-ary modulation for producing y. if(M<=8) % Modulation for PSK y=modulate(modem.pskmod(M),p); else % Modulation for QAM y=modulate(modem.qammod(M),p); end ylen = length(y); %Applying Mapping %q_out = ofdma_mapping(y,ylen); [iout,qout] = crmapping(y,ylen,fftlength,nd); % Apply IFFT operation outifft = ifft(iout,qout); % Cyclic Prefix Addition cp(count1,:) = cyclicpad(outifft,64); % Length of CP cplength = length(cp); % Conversion of data from parallel to serial out = reshape(cp(count1,:),1,cplength); % Signal transmits through AWGN channel. ynoisy = awgn(out,100,'measured'); % Addition of Rayleigh Fading c = rayleighchan(1/1000,100,[0 2e-5],[0 -9]); rf = filter(c,ynoisy); % Conversion of data from serial to parallel p2 = series2parallel(rf,cplength); re_par = real(p2); % Remove cyclic prefix rcp(count1,:) = decyclicpad(p2,64); rcplength = length(rcp); % FFT zzfft = fft(rcp(count1,:),fftlength); %Apply Demapping qq_out = ofdma_demapping(zzfft,fftlength); outfft = qq_out; % %Applying IFFT % zfft = ifft(qq_out); if (M<=8) % Demodulation of PSK at Reciever z=demodulate(modem.pskdemod(M),outfft); else % Demodulation of QAM at Reciever z=demodulate(modem.qamdemod(M),outfft); end % Conversion of data from parallel to serial xdash = reshape(z,1,NS) berr = 0 ; for a = 1:1:NS; if (xdash(:,a) == x(:,a)) berr = 0; else berr = berr+1; end end tberr(count1,:) = berr; Eb_No = 0:1:NS-1; Eb_No = 0.4*Eb_No; if(M<=8) ber(count1,:) = berawgn(Eb_No,'psk',M,'nondiff'); Pe(count1,:) = erfc(sqrt(0.9*Eb_No)*sin(pi/M)); else ber1(count1,:) = berawgn(0.9*Eb_No,'qam',M); Pe(count1,:) = 2*((1-(1/sqrt(M)))*erfc(sqrt((1.5*Eb_No)/(M-1)))); end for init = 1:1:32 switch M end end end M= 2^count1; end

figure() % Plot SNR and BER semilogy(Eb_No,ber(2,:),'k',Eb_No,ber(3,:),'g',Eb_No,ber1(5,:),'b',Eb_No,ber1(7,:),'r'); axis([0 25 0.0001 1]); xlabel('SNR [dB]') ylabel('BER') legend('BPSK','QPSK','16-QAM','64-QAM') title('OFDMA')

figure() % Plot Error Probability semilogy(Eb_No,Pe(2,:),'k',Eb_No,Pe(3,:),'r',Eb_No,Pe(5,:),'b',Eb_No,Pe(7,:),'g'); axis([0 50 0.0001 1]); xlabel('SNR [dB]') ylabel('Probability of Error') legend('BPSK','QPSK','16-QAM','64-QAM') title('OFDMA') h = spectrum.periodogram; figure() HS = psd(h,outifft,'SpectrumType','twosided','NFFT',NS,'FS',FS); plot(HS) xlabel('Sampling Frequency (2×BW) in MHz') ylabel('Power Spectral Density [dBm/Hz]') title('OFDMA') grid off;