Patent ID: 7197691

Claim:
A soft-in/soft-out (SISO) module comprising: a plurality of fusion modules arranged into a tree structure and adapted to perform parallel prefix and parallel suffix operations to compute forward and backward state metrics, respectively, wherein each fusion module is defined by the equation: C ⁡ ( k 0 , k 1 ) ⁢ = Δ ⁢ C ⁡ ( k 0 , m ) ⁢ ⊗ C ⁢ C ⁡ ( m , k 1 ) ⟺ C ⁡ ( s k 0 , s k 1 ) = min s m ⁢ [ C ⁡ ( s k 0 , s m ) + C ⁡ ( s m , s k 1 ) ] ⁢ ∀ s k 0 , s k 1 where C(k, m) is a matrix of minimum sequence metrics (MSM) of state pairs s k and s m based on soft-inputs between s k and s m .