A sampled analog MOS LSI adaptive filter

Describes a novel realization of an adaptive filter using sampled analog MOS LSI techniques in which the basic functional block is an electrically programmable transversal filter whose tap weights are modified according to the least mean square algorithm. A rotating tap weight structure is used to realize a 32-tap programmable transversal filter with features for the adaptive operation included on an NMOS silicon gate chip. A wide range of magnitude and phase characteristics have been used to test this system and the results on the residual error and the convergence time under different conditions are reported. Some practical limitations are also presented.