Method and apparatus for maximum likelihood sequence detection

A maximum likelihood sequence detector comprising:

• a bit separator means for receiving a branch metric and providing a first data word and a second data word;
• first adder means coupled to the bit separator means for receiving the first data word and a first path metric, and for providing a first adder output signal;
• a second adder means coupled to the bit separator means for receiving the first data word and a second path metric, which second path metric is different from the first path metric, and for providing a second adder output signal;
• a comparator means coupled to the first and second adder means for receiving the first path metric and the second path metric, and for providing a select signal;
• a multiplexor means coupled to the first adder means, the second adder means and the comparator means, for receiving the first and second adder output signals and having an output for providing a selected adder output signal in accordance with the select signal;
• and
• a third adder means coupled to the bit separator means and the multiplexor means for receiving the second data word and the selected adder output signal and for providing a third adder output signal.