Energy-efficient multi-standard early stopping criterion for low-density-parity-check iterative decoding
Résumé
Low-density-parity-check codes decoding relies on powerful iterative algorithms, whose implementation is often expensive in terms of complexity and power consumption. Several early stopping criteria (ESCs) have been proposed to reduce the number of iterations performed by a decoder with no (or limited) degradation of error correction performance. However, most of the existing ESCs have considered a reduced set of system parameters for validation and often have ignored the impacts related to a real hardware implementation. This study proposes a novel multi-standard early stopping criterion (MSESC) able to adapt dynamically to changes of code parameters, quantisation and channel conditions. A dedicated hardware architecture is devised and integrated in a multi-standard decoder, and compared with existing techniques. Post-layout results of the proposed MSESC show a small area increment (+1.3%) and a large decrement of the average energy consumption (up to 87.2%) with respect to the same decoder implemented with no ESC. Moreover, it is shown that MSESC offers an energy consumption reduction with respect to the state-of-the-art ESCs ranging from 4% [at high signal-to-noise ratio (SNR)] to 16% (at low SNR).