US Patent 7269226 Data processing method

A suboptimal method for searching for a symbol sequence, the method comprising the steps of: determining a channel impulse response; sampling a received signal; selecting at least one of the highest and/or most reliable impulse response values; determining a reference signal using at least one impulse response value and a symbol sequence assumed as transmitted; determining differential terms corresponding to the selected impulse response values for the signal sample and the reference signal; using the determined differential terms in a transition metric for searching for a symbol sequence; forming a survivor path by adding the symbol sequence provided by the transition metric to the survivor path formed so far.