Radio transmission apparatus and radio transmission method

Abstract

A radio transmission device capable of improving channel estimation precision for each frequency. In this device, an FFT unit ( 103 ) subjects a data signal to a Fourier transformation. A signal substitution unit ( 108 ) substitutes the frequency component of a portion of a plurality of frequency components composing the Fourier-transformed data signal, for a pilot signal. An IFFT unit ( 109 ) subjects the data signal, the frequency component of which has been partially substituted for the pilot signal, to an inverse Fourier transformation. A transmission RF unit ( 111 ) transmits the inversely Fourier-transformed data signal on a single carrier.

1 . A radio transmission apparatus comprising:
 a conversion section that converts a time-domain data signal into a frequency-domain data signal comprising frequency components;   a replacement section that thins out a first part of frequency components of the frequency-domain data signal, to obtain a thinned-out frequency-domain data signal;   a control section that controls a transmission power of a second part of the frequency components of the thinned-out frequency-domain data signal, the second part of the frequency components is different from the first part of frequency components;   an inversion section that inverts the thinned-out frequency-domain data signal into a thinned-out time-domain data signal; and   a transmission section that transmits the thinned-out time-domain data signal on a single carrier.   
     
     
         2 . The radio transmission apparatus according to  claim 1 , wherein the control section makes a value of the transmission power of the thinned-out frequency-domain data signal identical to a value of a transmission power assigned beforehand to the frequency-domain data signal before thinning out. 
     
     
         3 . The radio transmission apparatus according to  claim 1 , wherein the control section increases the transmission power of the second part of the frequency components by a predetermined proportion. 
     
     
         4 . The radio transmitting apparatus according to  claim 1 , wherein the control section increases the transmission power of the second part of the frequency components, by a predetermined value or up to the predetermined value. 
     
     
         5 . The radio transmission apparatus according to  claim 1 , wherein the control section increases equally a transmission power of each of a third part of the frequency components and a fourth part of the frequency components, the third part and the fourth part of the frequency components being different from both the first part of the frequency components and the second part of the frequency components. 
     
     
         6 . A radio transmission method performed at a radio transmission apparatus, comprising:
 converting a time-domain data signal into a frequency-domain data signal comprising frequency components;   thinning out a first part of frequency components of the frequency-domain data signal, to obtain a thinned-out frequency-domain data signal;   controlling a transmission power of a second part of the frequency components of the thinned-out frequency-domain data signal, the second part of the frequency components is different from the first part of frequency components;   inverting the thinned-out frequency-domain data signal into a thinned-out time-domain data signal; and   transmitting the thinned-out time-domain data signal on a single carrier.