1. A method for processing a signal, said method comprising steps of: precomputing intersymbol interference-free signal estimates for speculative sequences of one or more channel symbols; selecting a subset of said precomputed intersymbol interference-free signal estimates based on at least one decision from at least one corresponding state, wherein said selection is performed by a selection circuit having at least two pipeline stages connected in series, wherein each of said pipeline stages comprises at least one functional unit, and wherein said functional unit comprises a pipeline register and a multiplexer, and wherein at least one of said multiplexers selects from among precomputed intersymbol interference-free signal estimates previously selected by a prior pipeline stage; and selecting a path having a best path metric for a given state.