Non-uniform spatial coupling
Abstract
A new method for spatial coupling of low-density parity-check ensembles is proposed. The method is inspired from overlapped layered coding. Edges of local ensembles and those defining the spatial coupling are separately built. The new method allows the construction of non-uniform coupling chains with near-Shannon spatially-varying thresholds under iterative decoding. A direct application of non-uniform spatial coupling is unequal error protection of information.