For my research, i need to implement a Turbo Decoder to test a few things. I was able to write the BCJR algorithm code in MATLAB and for the most part, it works fine. By working fine, i mean that after a number of iterations, the number of errors reduces to zero or flatttens out. Where i am having a problem is that there are times where the number of errors randomly increases and decreases and that is affecting my results greatly. I was wondering if anyone has experienced this before and what the possible solution might be. If necessary i have added a .zip file of all the scripts needed to run the simulation in MATLAB. Thankyou