ADAPTIVE INGRESS FILTERING SYSTEM

摘要

A method and apparatus for filtering an undesired ingress signal from an input signal. The apparatus includes an adaptive filter including an ingress synthesizer (16) for creating the undesired ingress signal and an ingress subtractor (104) for subtracting the recreated ingress signal from the input signal. The ingress synthesizer (16) includes a replica generator (14) for generating replicas corresponding respectively to the input signal symbols, first summers for subtracting the replicas from the input signal for providing respective intermediate signals, second summers for subtracting a recreated ingress signal from the intermediate signals for providing respective error signals, a decision circuit (18) for selecting the intermediate signal corresponding to the error signal having the smallest magnitude, and an ingress generator (118) for processing the selected intermediate signal for providing the recreated ingress signal to the second summers and ingress subtractor (104). The ingress generator (118) converts the selected intermediate signal to component signals indicative of the magnitude, phase, frequency of the intermediate signal, individually filters the component signals and uses the filtered component signals for synthesizing the recreated ingress signal. The ingress subtractor subtracts the recreated ingress signal from the input signal for providing a filtered input signal where the undesired ingress signal has a reduced level as compared to the original signal.