Enhancement method according to the estimation of noise variance for the turbo decoder

This paper analyzes the BER performance of Turbo code which is adapted for DVB-RCS2 standard with various modulation schemes. Firstly this paper introduces the turbo codes and demapping algorithm and analyzes the effect of noise valiance on the turbo decoder and simulates the effect of the performance of the turbo decoder according to the noise variance by adding a pseudo noise. From the result of simulation it was derived the optimal pseudo noise value.