Arithmetic effects in adaptive lattice filters

The performance of adaptive lattice filters in finite precision real-time hardware is largely unknown because of the complexity of implementing lattice algorithms. The authors show how arithmetic effects can deleteriously manifest themselves in both the stochastic gradient and the least squares adaptive lattice filters. Computer simulations and experimental results are used to verify an analytical analysis describing implementation effects of adaptive lattice filters. It is found that the performance of adaptive lattice filters can be substantially improved by manipulating the time recursive coefficients using direct updating techniques. Results are compared to those obtained from LMS (least mean square) transversal adaptive filters