Patent ID: 9042481
Filing Date: 2015-05-26
Classification: H03F,H04B,H04L

Abstract:
1. A transmitter that generates a transmission signal by oversampling a modulated signal, the transmitter comprising: a modulator that performs a modulation process on an information sequence and that generates a constant envelope signal; an interpolator that inserts a predetermined number of signals identical in amplitude to signal points of the constant envelope signal between the signal points so that signal points including original signal points are located equidistantly; a Fourier transformer that transforms a signal obtained after the interpolator has performed a signal insertion process into a frequency-domain signal; a band-limiting filter that performs band limitation on a frequency-domain signal output from the Fourier transformer; an adder that adds an out-of-band signal that is a signal cut by the band-limiting filter to an in-band signal that is a signal not cut by the band-limiting filter; and an inverse Fourier transformer that transforms a signal obtained after the adder has performed an addition process into a time domain signal, wherein the adder performs addition to the in-band signal by individually frequency-shifting components of the out-of-band signal based on respective distances to the in-band signal on a frequency axis and by adding the frequency-shifted components to the in-band signal.