Deriving the Normalized Min-Sum Algorithm from Cooperative Optimization

Xiaofei Huang

doi:10.1109/itw2.2006.323788

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Deriving the Normalized Min-Sum Algorithm from Cooperative Optimization

Xiaofei Huang

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Abstract

The normalized min-sum algorithm can achieve near-optimal performance at decoding LDPC codes. However, it is a critical question to understand the mathematical principle underlying the algorithm. Traditionally, people thought that the normalized min-sum algorithm is a good approximation to the sum-product algorithm, the best known algorithm for decoding LDPC codes and Turbo codes. This paper offers an alternative approach to understand the normalized min-sum algorithm. The algorithm is derived directly from cooperative optimization, a newly discovered general method for global/combinatorial optimization. This approach provides us another theoretical basis for the algorithm and offers new insights on its power and limitation. It also gives us a general framework for designing new decoding algorithms.

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Xiaofei Huang. 2006-09-15. Deriving the Normalized Min-Sum Algorithm from Cooperative Optimization. https://doi.org/10.1109/itw2.2006.323788

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