Variability study for 3G and beyond mobile communications

Convolutional codes have been widely used in DS-CDMA systems for good performance and relatively low decoding complexity. In this article we, starting from the theoretical point, study the performance of convolutional codes in an environment where E_b/N₀ changes sinusoidally. We study four cases of this scenario. For each case we obtain some conclusions and give their analysis. In this article a very important characteristic, named additivity, is acquired.