Patent ID: 6049573
Filing Date: 2000-04-11
Classification: H03D,H03H

Abstract:
A polyphase quadrature digital tuner system which converts input signals to baseband inphase and quadrature signal components, said system comprising:a signal receiver which receives said input signals having a frequency centered around a predetermined carrier frequency;a signal processor which continuously samples said input signals and multiplies selected portions of said input signals by a value of 1 or -1 to produce discrete sequences of N input samples, where N is an integer;an inphase signal channel including a first set of N filters in a first filter stage each having respective filter coefficients, said first set of filters arranged to receive said discrete sequences, and a first signal summer which sums the outputs of said first set of N filters to produce said inphase signal component;a quadrature signal channel including a second set of N filters in said first filter stage each having respective filter coefficients, said second set of filters arranged to receive said discrete sequences, and a second signal summer which sums the outputs of said second set of N filters to produce said quadrature signal component; andmeans for providing said input samples to said inphase and quadrature signal channels so that each filter of both channels receives one input sample of each sequence.