Radio and communications technology
Modeling for LDPC serial decoding algorithm
Lei Jing
Abstract
Message-passing mechanism is an important factor affecting the performance of LDPC decoding. In this paper, we introduce briefly LDPC and sum product decoding algorithm based on floodwater message-passing mechanism proposed by Gallager. On this basis, we introduce a serial mechanism based on check nodes and propose a concrete and feasible decoding algorithm modeling. This serial decoding algorithm processes and passes the messages in a definite sequence of check nodes for ensuring that the updated messages can immediately enter the iterative process so as to improve convergence characteristics of the message passing, and use the feature of interdependence between messages to fuse the message passing steps to reduce required memory and decoding complexity. We use respectively the floodwater decoding algorithm and serial decoding algorithm to perform the performance simulation over AWGN channel. The simulation results show that the decoding performance could be improved by serial decoding algorithm.