Method of transmitting data using repetition coding

Abstract

A method of transmitting data in a wireless communication system is provided. The method includes generating duplicate data by using repetition coding, the duplicate data being the same as original data, shifting the phase of the duplicate data, and transmitting the original data and the phase-shifted duplicate data. The duplicate data is mapped to a modulation symbol having a different size or phase as that of the original data, thus to reduce the PAPR unlike the general repetition coding.

The invention claimed is: 
     
       1. A method of transmitting data in a wireless communication system, the method comprising:
 generating duplicate data by using repetition coding, the duplicate data being the same as original data;   changing the phase of the duplicate data;   allocating the original data and the phase-changed duplicate data to the subcarriers in a same orthogonal frequency division multiplexing (OFDM) symbol; and   transmitting the original data and the phase-changed duplicate data,   wherein the original data are transmitted through a first frequency band being comprised of contiguous subcarriers and the phase-changed duplicate data are transmitted through a second frequency band being comprised of contiguous subcarriers,   the first frequency band and the second frequency band are different frequency bands in frequency domain.   
     
     
       2. The method of  claim 1 , wherein the phase of the duplicate data are changed by a unitary matrix ‘C’ which is 
       
         
           
             
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       3. The method of  claim 1 , wherein the phase of the duplicate data are changed by a CAZAC (Constant Amplitude Zero Auto-Correlation) sequence. 
     
     
       4. A method of transmitting data in a wireless communication system, the method comprising:
 generating duplicate data which is the same as original data by using repetition coding;   changing the size and the phase of the duplicate data;   allocating the original data and the duplicate data with the changed size and phase to the subcarriers in a same orthogonal frequency division multiplexing (OFDM) symbol; and   transmitting the original data and the duplicate data with the changed size and phase.   
     
     
       5. The method of  claim 4 , further comprising:
 after the size and the phase of the duplicate data are changed, performing discrete fourier transform (DFT) and inverse fast fourier transform (IFFT) in sequence.   
     
     
       6. A data transmitter comprising:
 a data processing unit to perform repetition coding for original data to generate duplicate data;   a data changing unit to change the phase of the duplicate data; and   a subcarrier allocating unit to map the original data and the phase-changed duplicate data to subcarriers in a same orthogonal frequency division multiplexing (OFDM) symbol,   wherein the original data are transmitted through a first frequency band being comprised of contiguous subcarriers and the phase-changed duplicate data are transmitted through a second frequency band being comprised of contiguous subcarriers,   the first frequency band and the second frequency band are different frequency bands in frequency domain.   
     
     
       7. A method of transmitting data in a wireless communication system, the method comprising:
 generating second data from first data by using a coding scheme,   the second data taken from the first data, wherein the coding scheme is used to distribute the second data beside the first data and to change a phase of the second data;   transmitting the first data and the second data, wherein the second data is allocated after the first data,
 wherein the first data is transmitted through first frequency values being comprised of contiguous subcarriers and the second data is transmitted through second frequency values being comprised of contiguous subcarriers, 
 wherein the first frequency values and the second frequency values are different in a frequency domain. 
   
     
     
       8. The method of claim 7,
 wherein a phase difference between the first data and the second data is one of 0, π/2, π/4 and π/6.   
     
     
       9. The method of claim 7,
 wherein the second data is generated based on a Cazac sequence.   
     
     
       10. The method of claim 7, the method further includes:
 modulating the first data and the second data.   
     
     
       11. An apparatus of transmitting data in a wireless communication system, the apparatus comprising:
 a data processor for generating second data from first data by using a coding scheme,   the second data taken from the first data, wherein the coding scheme is used to distribute the second data beside the first data and to change a phase of the second data,   a transmitter for transmitting the first data and the second data, wherein the second data is allocated after a part of the first data,
 wherein the first data is transmitted through first frequency values being comprised of contiguous subcarriers and the second data is transmitted through second frequency values being comprised of contiguous subcarriers, 
 wherein the first frequency values and the second frequency values are different in a frequency domain. 
   
     
     
       12. The apparatus of claim 11,
 wherein a phase difference between the first data and the second data is one of 0, π/2, π/4 and π/6.   
     
     
       13. The apparatus of claim 11,
 wherein the second data is generated based on a Cazac sequence.   
     
     
       14. The apparatus of claim 11, the apparatus further includes:
 a modulator to modulate the first data and the second data.