CCSDS 131.2-B-1 Serial Concatenated Convolutional Turbo Decoder Architecture for Efficient FPGA Implementation

Most of the turbo encoding schemes at standards are parallel-based, so different architectures for efficient implementation are common in the literature. However, a serial turbo decoder is not that common. This scheme is used in CCSDS 131.2-B-1 standard, which is attracting much of attention recently due to its higher performance for satellite communications. In this paper, an efficient architecture for the decoder is proposed and analyzed. It is intended to show an architecture that can be modeled in a circuit description language (such as VHDL and Verilog) in such a way that it can be easily implemented on a Field Programmable Gate Array (FPGA). This work describes in detail this architecture explaining the encoding operations that are performed at the transmitter and then, how to undo them at the receiver. The proposed algorithm works by using independent components to divide the tasks and to obtain a pipeline architecture to improve the efficiency. The results of simulating and implementing the proposed architecture on a Xilinx Zynq UltraScale+ RFSoC ZCU28DR board with XCZU28DR-2FFVG1517E RFSoC are shown. The final results presented demonstrate how the hardware operations give equivalent results to the software simulation and do not consume board resources aggressively as usually the turbodecoder does.