Patent ID: 6195782
Filing Date: 2001-02-27
Classification: H03M,H04L

Abstract:
A system for estimating a sequence of transmitted symbols from a first signal, wherein the first signal is received from a communication channel, the system comprising:a sampling device coupled to receive said first signal and configured to produce a sequence of samples of said first signal;a digital signal processor (DSP) configured:to calculate a set of channel coefficients which represent said communication channel;to calculate combination values for a plurality of states based on said channel coefficients, wherein each state of said plurality of states comprises an ordered collection of possible values for the transmitted symbols;a hardware module configured to receive a first sample of said sequence of samples and configured to calculate a survivor state value and a minimizing path metric value for each state of said plurality of states;wherein said survivor state value and said minimizing path metric value for each state of said plurality of states are used to estimate said sequence of transmitted symbols;wherein said hardware module is configured to access a plurality of stored error values, wherein said plurality of stored error values are used to calculate said survivor state value and said minimizing path metric value for each state of said plurality of states;wherein said hardware module includes a state counter and a combination counter, wherein said state counter and combination counter are configured to control:a selection of a first combination value of said combination values;a selection of a first branch product value of said plurality of branch product values; anda selection of a first error value from said plurality of stored error values;wherein said first combination value, said first branch product value, and said first error value are used to determine said survivor state value and said minimizing path metric for one of said plurality of states.