ARTÍCULO

LDPC codes for non-uniform memoryless sources and unequal energy allocation

Autores: Ochoa Álvarez, Idoia (Autor de correspondencia); Crespo Bofill, Pedro; Hernáez Arrazola, Mikel
Título de la revista: IEEE COMMUNICATIONS LETTERS
ISSN: 1089-7798
Volumen: 14
Número: 9
Páginas: 794 - 796
Fecha de publicación: 2010
Lugar: WOS
Resumen:
In this paper, we design a new energy allocation strategy for non-uniform binary memoryless sources encoded by Low-Density Parity-Check (LDPC) codes and sent over Additive White Gaussian Noise (AWGN) channels. The new approach estimates the a priori probabilities of the encoded symbols, and uses this information to allocate more energy to the transmitted symbols that occur less likely. It can be applied to systematic and non-systematic LDPC codes, improving in both cases the performance of previous LDPC based schemes using binary signaling. The decoder introduces the source non-uniformity and estimates the source symbols by applying the SPA (Sum Product Algorithm) over the factor graph describing the code.