Patent ID: 8554817

Claim:
A device for converting a first digital signal having a first sampling rate into a second digital signal having a sampling rate equal to a predetermined second sampling rate comprising: a numeric controlled oscillator for generating calibrating coefficient using the first sampling rate and the second sampling rate; and an interpolation filter for interpolating the first digital signal using the calibrating coefficient to obtain the second digital signal, when the ratio of the first sampling rate to the second sampling rate is a repeating infinite decimal, the numeric controlled oscillator calculating at least two calibrating coefficient values and outputting the calibrating coefficient values according to a predetermined rule such that an accumulated value of the output calibrating coefficient oscillates about an accumulated value of μ, or at regularly spaced points along time axis, the accumulated value of the output calibrating coefficient equals to the accumulated value of μ, where μ=( L−M )/ M, L represents the first sampling rate, and M represents the second sampling rate.