Trapping Set Analysis of Horizontal Layered Decoder

Abstract

In this paper, we present how the decoding performance of layered decoder can be analyzed using trapping sets. Surprisingly, a simple horizontal layered Gallager-B decoder breaks all weight-3 error patterns on a (5,3) trapping set successfully, resulting in a steeper slope in frame error rate (FER) curves compared to a flooding schedule decoder. Theoretical validation of the results is also done using a semi- analytical method for computing the error floors of LDPC codes on a binary symmetric channel decoded using layered Gallager-B algorithm.