Checking adjacent bits in Matlab

Hi

I have to generate a specific type of Pulse position modulation for which i am generating 100 random bits and have to check every two adjacent bits and generate a waveform accordingly.

For example

lets say the generated bits are 11001001

first I need to check the first two bits which are 11 and then the next two bits which are 00 and the following two bits are 10 and the last to bits 01 I have written the following code to check the bits

clear all;
N=10000;
Nbit=100;
t=0:.001:6.4;

% Generate Binary signal
wb=round(rand(1,Nbit));
% wb=wb';
y=size(wb);
i=1:Nbit
j=i+1;
if wb(i) ==0 & wb(j)==0
  y(i)=0;  
elseif wb(i) ==0 & wb(j)==1
    y(i)=1;
elseif wb(i) ==1 & wb(j)==0
        y(i)=0;
    else 
        y(i)=0;
    end

the output always gives 0.

Would really appreciate if someone could help me with this

Thank you

Answer 1

[Walter Roberson]

Change the

i=1:Nbit

to

for i=1:Nbit

and add

end

after your the last "end" of your "if" chain.

[Mila C]

Hi, thank you so much for the help.

I changed the code according to it and modified abit :)

clear all;
N=10000;
Nbit=100;
t=0:.001:6.4;

% Generate Binary signal
wb=round(rand(1,Nbit));
wb=wb';
y=size(wb);

for k=1:Nbit;
i=1:2:Nbit
j=2:2:Nbit;
if wb(i) ==0 & wb(j)==0
  y(i)=0;  
elseif wb(i) ==0 & wb(j)==1
    y(i)=1;
elseif wb(i) ==1 & wb(j)==0
        y(i)=0;
    else 
        y(i)=1;
    end
end