Research And Implement On Two EFEC Algorithms In G.975.1

With the optical communication technology to the development of long distance, high capacity and high speed, the problems that crosstalk between optical signals, signal synchronization, timing, recovery, would follow. All of these would lead to production of optical communication in error, and reduce the reliability of communication. The reduction of communication reliability has ultimately restricted the improvement of communication quality. The extension of communication distance, large-scale multiplexing applications, and streamline the cost of communications equipment, these would greatly hinder the further development of optical communication. Therefore, how to overcome the noise in the random channel, and how to reduce the errors in information transmission without reducing the efficiency of information transmission, that is how to solve the contradiction between the system's effectiveness and reliability, would become the hot problem of the optical communication technology. A kind of stronger error correction capability of the new super-FEC code type has become a focus for researchers. ITU-T G.975.1 standard also introduces the eight kinds of super error correction performance pattern in detail.In addition, BCH code is a good linear error-correcting code that would ever be found, it would be widely used in mobile communications, wireless paging systems and fiber-optic communication. In this paper, the characteristics of BCH codes, two of the super-FEC algorithms are studied separately.In Chapter three, the traditional concatenated codes and improvement of concatenated codes are introduced firstly. Then the frame structure of the concatenated BCH super FEC codes has been studied in detail in 1.3, and the corresponding compiled code scheme is given. The BCH encoding, decoding and the frame structure of the transformation have been implemented through the MATLAB programming.In Chapter four, the frame structure of the two orthogonally concatenated BCH super FEC code has been studied in 1.7, and the row and column codewords allocation and mapping from G.975 compliant framing schemes are given. Moreover, this chapter introduces the structure of extension field operations and field elements, as preparation for the next decoding algorithm. In the concept of the encoding and decoding, the encoding based on polynomial division circuit and iterative decoding algorithm based on BM and mainly introduced. The BCH encoding and decoding have been implemented through the MATLAB programming,. The BCH code the error rate performance has been analyzed in different structures.The results show that:with the same error channel, the frames structure of two BCH codes referenced in 1.3 and 1.7, have more excellent error correction capability compared to ordinary BCH codes. The results have some reference value to improve communication reliability for the further research and designing.