Turbo Codes―A New PCCC Design

Spyridon K. Chronopoulos, Giorgos Tatsis, Panos Kostarakis

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DOI: 10.4236/cn.2011.34027                

Abstract

Coding techniques have always been a major area of scientific interest. Due to this interest, many coding schemes were invented. Eventually, their implementation in various systems contributed in the evolvement of Wireless Communications. A breakthrough was definitely Turbo coding. Particularly, the concept of joining two or more convolutional encoders in parallel (PCCC) or in serial (SCCC), along with the iterative decoding technique, literally raised the expectations of the anticipated BER performance. In fact, Concatenated Convolutional Codes clearly outperform convolutional codes. Moreover, various systems, either under development or either for future use, will have high standards. The previous systems should present exceptional tolerance of noise effects and consequently a low overall number of received errors. For this purpose a new PCCC design was developed. The system’s performance analysis, using an AWGN channel, showed better results for various iterations compared to other schemes such as typical PCCC, SCCC and finally a Convolutional encoder with a Viterbi decoder.

Keywords

Turbo Codes, Convolutional Codes, SOVA, SISO, SCCC, PCCC, Random Interleavers, Iterative Decoding, APP Decoder, Puncturing, AWGN, Noise Variance

Conflicts of Interest

The authors declare no conflicts of interest.

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