Patent ID: 7499497

Claim:
An impulse noise suppression apparatus applied in an Orthogonal Frequency Division Multiplexing (OFDM) communication system for suppressing an impulse noise in a first time-domain signal to generate an output signal, the impulse suppression apparatus comprising: a noise blanker for processing the first time-domain signal to generate a second time-domain signal, wherein if an absolute value of the first time-domain signal corresponding to a time instant is greater than a first threshold value, the second time-domain signal corresponding to the time instant is generated to have an absolute value not greater than a predetermined value; and if the absolute value of the first time-domain signal corresponding to the time instant is not greater than the first threshold value, the second time-domain signal corresponding to the time instant is generated according to the value of the first time-domain signal corresponding to the time instant; a first Fourier transform unit, coupled to the noise blanker, for performing a Fourier transform on the second time-domain signal to generate a frequency-domain signal, wherein the frequency-domain signal is composed of a plurality of sub-carrier signals and each sub-carrier signal corresponds to one of a plurality of sub-carriers; an equalizing module, coupled to the first Fourier transform unit, for generating an equalized signal by equalizing the frequency-domain signal according to a plurality of channel estimation values respectively corresponding to the plurality of sub-carriers, wherein the equalized signal is composed of a plurality of equalized values, and each equalized value corresponds to one of the plurality of sub-carriers; a decision unit, coupled to the equalizing module, for generating a decision signal according to the equalized signal, wherein the decision signal is composed of a plurality of decision values and each decision value corresponds to one of the plurality of sub-carriers; and a compensation module, coupled to the equalizing module and the decision unit, for estimating a time-domain compensation signal corresponding to the difference between the equalized signal and the decision signal, and for generating the output signal by calibrating the equalized signal according to the time-domain compensation signal, wherein the output signal is composed of a plurality of output values and each output value corresponds to one of the plurality of sub-carriers.