Apparatus and method for processing a digital signal in a frequency domain linear equalizer

The present disclosure relates to an apparatus and method of processing a digital signal, wherein an input signal is transformed into the frequency domain by applying a fast Fourier transformation (FFT) processing to obtain a transformed input signal. Positive and negative frequency components of the transformed input signal are separated and respective ones of the separated positive and negative frequency components are separately processed by respective digital filtering to obtain filtered frequency components. The filtered frequency components are combined in the frequency domain using a down-sampling operation for down-sampling the filtered frequency components from an input number of samples per symbol to a different output number of samples per symbol, and the combined output components are converted into the time domain by applying an IFFT processing.