Device and method for viterbi equalization with metric increments calculated in advance

A Viterbi equalizer for equalizing a data signal, comprising:

• an input for receiving estimated channel impulse responses representing the data signal in a current time step k;
• a calculation unit connected to said input and configured to calculate metric increments for a plurality of state transitions starting from a given channel state relating to the time step k to channel states in a following time step k+1 to be reached by the state transitions;
• an output memory connected to receive the metric increments from said calculation unit and for storing the metric increments;
• and
• an add-compare-select unit connected to said output memory and operable to carry out, with reference to each channel state relating to the time step k, an add-compare-select operation for determining a given state transition leading, with minimal metrics, from one possible predecessor state relating to a predecessor time step to a destination time step.

A method for equalizing a data signal transmitted via a channel that is subject to interference, wherein the data signal is equalized with the Viterbi algorithm, and the method comprises the following steps:

• calculating, for all transitions between a given state of a time step k and states of a time step k+1 that can be reached from the given state, associated metric increments, and storing the metric increments in an output memory;
• calling up the metric increments from the output memory;
• and
• determining, with an add-compare-select operation utilizing the metric increments called up from the output memory, a transition leading with minimum metrics from one possible predecessor state relating to the time step k to a specific destination state relating to the time step k+1.