A fast pipelined CORDIC-based adaptive lattice filter

CORDIC-based adaptive lattice prediction algorithms and a pipelined CORDIC architecture for unnormalized lattice predictors are presented. One directly updates the CORDIC rotation angles theta /sub i/, i=1 . . . N, rather than the predictor unnormalized reflection coefficients, k/sub i/=tanh theta /sub i/. This updating scheme guarantees the minimum phase condition and will take full advantage of the CORDIC architecture. Moreover, to facilitate fully pipelined operation a delayed updating algorithm which updates the rotation angle based on delayed prediction errors is developed. This algorithm leads to a modular architecture and fast throughput VLSI implementation. The authors also study the application of the delayed updating algorithm to adaptive QRS detection, for the analysis of electrocardiographic (ECG) signals.<>