SIGNAL PROCESSING APPARATUS AND SIGNAL PROCESSING METHOD
According to an aspect of the present invention, there is provided a signal processing device including: a Fourier transform processing unit that converts an input signal into a frequency domain signal for each block having a size N; a multiplication processing unit that performs filtering processing on the converted frequency domain signal by using a filter weighting coefficient; an inverse Fourier transform processing unit that performs inverse Fourier transform processing on the frequency domain signal on which the filtering processing is performed; and an output signal selection unit that stores N/2+Δ symbols centered on an N/2-th output symbol from the head among output symbols having a size N which are obtained by performing inverse Fourier transform processing, and outputs a signal obtained by discarding output symbols other than the stored output symbols.
1 . A signal processing device comprising:
a Fourier transform processing circuitry that converts an input signal into a frequency domain signal for each block having a size N;
a multiplication processing circuitry that performs filtering processing on the frequency domain signal converted by the Fourier transform processing circuitry by using a filter weighting coefficient;
an inverse Fourier transform processing circuitry that performs inverse Fourier transform processing on the frequency domain signal on which the filtering processing is performed by the multiplication processing circuitry; and
an output signal selection circuitry that stores N/2+Δ (Δ is a positive integer) symbols centered on an N/2-th output symbol from the head among output symbols having a size N which are obtained by performing inverse Fourier transform processing by the inverse Fourier transform processing circuitry, and outputs a signal obtained by discarding output symbols other than the stored output symbols.
2 . The signal processing device according to claim 1 , further comprising:
a zero addition circuitry that outputs a signal obtained by adding zero to a difference vector obtained from a difference between the signal output by the output signal selection circuitry and a desired signal,
wherein the zero addition circuitry sets components corresponding to the output symbols discarded by the output signal selection circuitry to zero.
3 . The signal processing device according to claim 2 , further comprising:
another Fourier transform processing circuitry that outputs a signal obtained by performing Fourier transform on the signal to which zero is added by the zero addition circuitry.
4 . The signal processing device according to claim 3 , further comprising:
a complex conjugate processing circuitry that performs complex conjugate processing on the signal output by the Fourier transform processing circuitry; and
an updating circuitry that updates the filter weighting coefficient by using the signal on which complex conjugate processing is performed by the complex conjugate processing circuitry and the signal output by the another Fourier transform processing circuitry.
5 . A signal processing method comprising:
converting an input signal into a frequency domain signal for each block having a size N;
performing filtering processing on the frequency domain signal converted by the converting by using a filter weighting coefficient;
performing inverse Fourier transform processing on the frequency domain signal on which the filtering processing is performed by the performing the filtering processing; and
storing N/2+Δ (Δ is a positive integer) symbols centered on an N/2-th output symbol from the head among output symbols having a size N which are obtained by performing inverse Fourier transform processing by the performing the inverse Fourier transform processing, and outputting a signal obtained by discarding output symbols other than the stored output symbols.