Patent ID: 7813450
Filing Date: 2010-10-12
Classification: H04B,H04L

Abstract:
1. A method for reducing Radio Frequency Interference (RFI) interference in a Discrete Multi-tone Transmission (DMT) data transmission comprising the steps of: generating a compensation signal for the purpose of reducing an RFI interference signal superposed on a transmitted DMT reception signal using only carrier frequencies of said DMT reception signal in the vicinity of the interface frequency of said interference signal which are not utilized for the data transmission, said generating comprising providing at least one normalized complex spectral function for all carriers of said interference signal, carrying out an Fast Fourier Transform (FFT) for the purpose of obtaining spectral value of said DMT reception signal; determining a frequency maximum of said interference signal situated within a current DMT data frame of said DMT reception signal; assigning an observation window to said spectral values of said current DMT frame of said DMT reception signal, said observation window comprising at least one of said interference frequency; calculating a complex evaluating coefficient for said current DMT frame, said complex evaluating coefficient resulting from said spectral values of said DMT reception signal within said observation window and said complex evaluating coefficient being identical for all frequencies with said current DMT frame; and calculating said compensation signal by multiplying said normalized complex spectral function with said complex evaluating coefficient, and shifting said compensation signal to the position of said frequency maximum of said respective interference signal and which provides, on the output side a further compensation signal adapted to the position of said interference signal removing said compensation signal from said DMT reception signal superposed with said interference signal.