Double binary turbo codes analysis and decoder implementation

Classical Turbo Code presented in 1993 by Berrau et al. received great attention due to its near Shannon Limit decoding performance. Double Binary Circular Turbo Code is an improvement on Classical Turbo Code and widely used in today’s communication standards, such as IEEE 802.16 (WIMAX) and DVBRSC. Compared to Classical Turbo Codes, DB-CTC has better error-correcting capability but more computational complexity for the decoder scheme. In this work, various methods, offered to decrease the computational complexity and memory requirements of DB-CTC decoder in the literature, are analyzed to find the optimum solution for the FPGA implementation of the decoder. IEEE 802.16 standard is taken into account for all simulations presented in this work and different simulations are performed according to the specifications given in the standard. An efficient DB-CTC decoder is implemented on an FPGA board and compared with other implementations in the literature.