Iterative Reduced-Complexity Graph-Based Detection for LDPC Coded 2D Recording Channels

In this paper, we consider joint detection and decoding for low-density parity-check (LDPC) coded two-dimensional (2D) intersymbol interference (ISI) channels, where message-passing is performed over an overall factor graph representing both the code structure and the channel model. We propose a low-complexity channel detector based on the Chase decoding algorithm to simplify the check node operation by restricting the a posteriori probability (APP) computation to a small subset of candidate vectors. Simulation results show that the proposed receiver provides an adjustable performance/complexity tradeoff and performs close to the full-complexity graph-based receiver.