Patent ID: 8611204
Filing Date: 2013-12-17
Classification: H04L

Abstract:
1. A digital signal multiplexing apparatus for frequency-multiplexing signals of a plurality of channels to output a frequency-multiplexed signal, comprising: a first unit configured to write an input signal into a memory corresponding to a channel of the input signal for each channel of the plurality of channels at a rate corresponding to a bandwidth of the respective channel; a second unit configured to read the input signal of each channel for a predetermined period from the respective memory and to perform, on the input signal read from the respective memory, discrete Fourier transform of a length that is the same as a number of samples of the input signal so as to output samples of the frequency domain; a third unit configured to output samples existing within an occupied band of each channel from the samples of the frequency domain; a fourth unit configured to arrange the samples existing within the occupied band of each channel according to frequency assignment of the plurality of channels to be frequency-multiplexed; and a fifth unit configured to perform discrete inverse Fourier transform on the samples arranged according to the frequency assignment of the plurality of channels to be frequency-multiplexed.