US Patent 7594161 Map decoding

A method of approximating the generation of a logarithm of a sum of exponents, for use in a log-MAP decoding operation, by performing a first operation on the data, calculating a correction term in a second operation, and adding the correction term to the results of the first operation, in which the second operation comprises calculating an approximate correction term by an operation including at least one division stage in which a first result obtained based on said data and at least a first coefficient is divided by a second result obtained based on said data and at least a second coefficient.