Integrated structure for a convolutive viterbi decoder

A Viterbi convolutive decoder comprising:

• a network of N add-compare-select units implemented in a technology having at least three metallization layers, each of the N add-compare-select units being respectively associated with one state of an N state trellis of the Viterbi convolutive decoder, the N add-compare-select units being physically arranged within the Viterbi convolutive decoder to form two parallel columns, each respective parallel column of the two parallel columns including pairs of add-compare-select units physically arranged along a column height, each pair of add-compare-select units including first and second add-compare-select units that are associated with states 2n and 2n+1 modulo-N, respectively, where n is a positive integer, the first add-compare-select unit being coupled, for receiving a first path metric, to an add-compare-select unit that is associated with one of states n and n+N/2 of a close pair of add-compare-select units and the second add-compare-select unit being coupled, for receiving a second path metric, to an add-compare-select unit that is associated with the other of states n and n+N/2 of a remote pair of add-compare-select units;
• a common channel to separate the two parallel columns, the common channel including interconnections between remote pairs of add-compare-select units;
• and
• interconnection means, formed in the first and second add-compare-select units of each pair of add-compare-select units, for interconnecting the first and second add-compare-select units along a height of each respective parallel column to reduce a surface area of the network of N add-compare-select units.