Abstract: Turbo codes have performance superior than all other coding techniques. Main factors that make turbo codes so efficient include parallel concatenation structure of the encoding system recursive convolutional encoder, interleave, puncturing pattern and iterative decoding. Puncturing is the tradeoff between rate and performance. Puncturing increases code rate without increasing complexity for code rate from 1/3 to or more and decreases free distance of code. The redundant bits in coding decrease the bandwidth efficiency.In this paper the desired turbo coding rates providing methods using the puncturing process and also the effect of this process on BER.

Keywords: Turbo coding, Puncturing, Interleaver, Iterative decoding, Convolutional code.