Patent ID: 6141671
Filing Date: 2000-10-31
Classification: H03H

Abstract:
A system for converting a sequence of input samples at a first sampling rate defining an input period to a sequence of output samples at a second sampling rate, comprising:a coefficient memory having locations, selectable through address inputs, in which filter coefficients are stored;a time period measurement device having inputs for receiving signals indicative of an arrival of an input sample and an arrival of an output sample request and a clock input for receiving a clock signal providing pulses occurring at a rate independent of and substantially higher than the first and second sampling rates, and having an output providing a measure of time between the arrival of an input sample and the arrival of a subsequent output sample request according to the received clock signal;an access device for the coefficient memory having an input connected to receive the measure of time output from the time period measurement device and an input for receiving a signal indicative of an output sample request, and having outputs connected to the address inputs of the coefficient memory for applying coefficient addresses determined by the access device as a function of the measured time period; andan accumulator having an input for receiving the sequence of input samples and an input for receiving the selected filter coefficients and an output providing a sum of products of the sequence of input samples and the selected filter coefficients.