??? Error using ==> reshape Size can only have one unknown dimension. Error in ==> SpatialMod at 5 x1 = reshape(bi​t_T,Nobit+​Nt,[]);

when i try to run the program getting the above mentioned error. how to correct it.

function simulation_of_SM_iMRC()
global M Mt hmodem bit_T 
clear all; 
clear UnUsEdVaRiAbLe_To_IgNoRe;
clc;
mode = 1;                      

M = 16;   
Mt = 4;
Mr = 4;
bit_SMsym = log2(M*Mt);      % number of bit per sysmbol
Nbits = bit_SMsym*1e4;       % Number of bits to be simulated.

hmodem =   modem.qammod('M',M,  'SymbolOrder', 'Gray','InputType', 'bit');
hdemodem = modem.qamdemod('M', M,'SymbolOrder','Gray','OutputType','bit');
Eac = (mean(hmodem.Constellation .* conj(hmodem.Constellation)));                     
SNR = 0 : 2 :24;             % signal-to-noise ratio in dB
No= (Eac)*10.^(-SNR/10);     % noise variance

L_SNR=length(SNR);
ber= zeros (L_SNR,1); 
bit_R=zeros(Nbits, 1);
bit_T = randi([0 1],Nbits,1);
[mod_T ante]= SpatialMod();    
mod_T = mod_T.';

for ii=1:L_SNR    
    for j = 1 : size(mod_T ,2)
        channel = sqrt(.5)*( randn(Mr,Mt,1) + 1i*randn(Mr,Mt,1)); 
        noise = sqrt(.5)*(randn(Mr , 1) + 1i*randn(Mr , 1))* sqrt(No(ii));      
        p = diag(channel'*channel);               
        switch mode
            case 1
               y = channel(:,ante(j))*(mod_T(ante(j) ,j)./sqrt(p(ante(j)))) + noise;  
               z = (channel'*y)./p.^.5;
            case 2
               y = channel(:,ante(j)) * mod_T(ante(j) ,j) + noise ; 
               z = (channel'*y)./p;
        end        
        [UnUsEdVaRiAbLe_To_IgNoRe, ant_est] = max(abs(z));
        bi_ant = de2bi(ant_est - 1 ,  log2(Mt)  ,'left-msb');
        bi_mod = demodulate(hdemodem, z(ant_est,1) );
        bit_R( (j-1)*bit_SMsym+1 : (j-1)*bit_SMsym+bit_SMsym,1) = [bi_ant.' ; bi_mod];

      end
      [UnUsEdVaRiAbLe_To_IgNoRe,ber(ii,1)] = biterr(bit_T(:,1),bit_R(:));
  end
  figure(1);
  semilogy(SNR,ber(:,1),'color',[0,0.75,0.75],'linestyle','--','LineWidth',2.4);
  grid on;

function [signal ant_no]= SpatialMod()
global M Mt hmodem bit_T
Nt    = log2(Mt);
Nobit = log2(M);
x1 = reshape(bit_T,Nobit+Nt,[]);

ant_no =  bi2de([x1(1:Nt,:)].' , 'left-msb') + 1;
digMod = modulate(hmodem,x1(Nt+1:end,:));

signal = zeros(Mt , length(digMod));

for i = 1 : length(digMod)
    signal( ant_no(i) , i) = digMod(i);
end

signal = signal.';

Answer 1

[Walter Roberson]

Get rid of the "clear all"

[Kartickeyan V]

i tried it erroe is rectified but the program stuck in busy

[Walter Roberson]

I loaded in your code, commented out the "clear all", and added in a waitbar. It proceeds as expected. It takes a moment to finish, but not all that long.