Patent ID: 8489661

Claim:
A sample rate converter circuit comprising: an input to receive a discrete-time input signal, wherein the discrete-time input signal includes first discrete-time samples obtained at a sampling frequency f S0 ; and a digital sample rate conversion filter and interpolator, coupled to the input, having a transfer function modeled from a continuous-time filter, and the digital sample rate conversion filter comprises an infinite impulse response (IIR) filter, wherein the digital sample rate conversion filter is configured to (i) receive the input signal and (ii) generate output samples of the IIR filter having a sampling frequency of f S0 and auxiliary data wherein the auxiliary data is distinct from the output samples of the IIR filter and comprises a plurality of values within the IIR filter, and the interpolator is configured to determine second discrete-time output samples from output samples of the IIR filter and the auxiliary data at a sampling frequency f S1 , the second discrete-time output samples having values temporally between values of adjacent-in-time samples of a subset of the output samples of the IIR filter, wherein (i) f S0 does not equal f S1 and (ii) the values of the output samples of the IIR filter are determined in accordance with the model of the continuous-time filter.