Four different classes of adaptive signal cancelers can be used to eliminate narrow-band interference from a broadband signal: (1) cascaded second- order notch filters, (2) high-order in-line notch filters, (3) second-order bandpass noise cancelers, and (4) high-order bandpass noise cancelers. Of the four, a structure based on second-order bandpass filters used as signal cancelers is found to perform better than the other structures. The adaptive algorithm for these filters has been proposed by Kwan and Martin and modified by Petraglia, Mitra, and Szczupak. The Kwan and Martin structure can be reduced in hardware complexity without degrading performance using a new adaptive algorithm that out-performs any of the other known structures or algorithms. This new structure is particularly suited to the elimination of narrow-band interference in broadband Bi-Phase Shift-Key (BPSK) signals with and without background noise.... Narrow-band interference removal, Adaptive interference removal, Pipeline digital filters.