Patent ID: 7480342

Claim:
A method for use in a decoder, comprising the steps of: generating a reliability value from a received multilevel signal in relation to a number of predetermined signal symbols each associated with a corresponding bit sequence including a first bit position, the soft value being indicative of a reliability value for the first bit position; identifying a first one of the number of signal symbols as being closest to the received multilevel signal; estimating the soft value as a function of a first distance between the received signal and the first signal symbol and of a second distance between the received signal and a second one of the number of signal symbols that is closest to the first signal symbol and corresponds to a different binary value at the first bit position of the respective associated bit sequence than the first signal symbol; inputting the reliability value into a decoder that uses soft values as an input; and wherein estimating the soft value comprises estimating the second distance by a stored third distance between the first signal symbol and the second signal symbol.