Patent ID: 7436968
Filing Date: 2008-10-14
Classification: G11B,H03H

Abstract:
1. An adaptive noise reduction method including an adaptive filter for obtaining a signal approximate to a periodic signal to be reduced from a reference input pulse signal synchronous with said periodic signal to be reduced within a main input signal, and composition means for subtracting an output signal of said adaptive filter from said main input signal, in which an output signal of said composition means is fed back to said adaptive filter and said adaptive filter performs adaptation processing so that noise power of the output signal of said composition means may be minimum, comprising the steps of: providing a ring-shaped memory constituting said adaptive filter, providing a read-address generator for generating read addresses of the ring-shaped memory, and providing a write-address generator for generating write addresses thereof different from said read addresses, and wherein relative phase of address offset between said read address and said write address is made to be variable.