Patent ID: 7262716
Filing Date: 2007-08-28
Classification: H03H

Abstract:
1. An asynchronous sample rate converter comprising: (a) interpolation and filter circuitry for interpolating and filtering an audio input signal to produce a filtered, up-sampled first signal; (b) a memory for receiving the first signal and storing samples thereof and presenting stored samples from locations of the memory determined by a read address; (c) interpolation and resampling circuitry for operating on the presented samples to produce a continuous-time signal which is resampled to produce a discrete-time signal that is up-sampled relative to a desired output signal; (d) down-sampling and filtering circuitry for operating on the discrete-time signal to produce an output signal; (e) sample rate estimating circuitry for computing a difference signal representative of a time at which a data sample of the audio input signal is received and a time at which a corresponding audio output sample is required; (f) address generation circuitry for generating the read address in response to the difference signal; and (g) coefficient calculation circuitry for calculating filter coefficients for the interpolation and resampling circuitry in response to the difference signal.