A pole-zero complex adaptive joint process least-squares lattice

A pole-zero adaptive noise cancelling structure is described and its relevance to the adaptive beamforming problem discussed. An embedding approach is taken where a scalar ARMA (autoregressive moving-average) process is embedded into a two-channel AR process. Drawing on previously developed recursions for the joint process, multichannel, least-squares lattice, the recursions for the pole-zero adaptive noise canceller are implemented. A performance comparison is made between the resulting pole-zero adaptive noise cancelling structure and the all-zero least-squares lattice adaptive noise cancelling structure. The ability to implement adaptive poles is shown to be particularly advantageous in the region where the reference channel has a null