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 duplicate data based on a repetition of a part of original data, the duplicate data being the same as the part of original data, wherein a specific sequence is applied to the duplicate data;   disposing the original data and the duplicate data, wherein the original data and the duplicate data are allocated to subcarriers in at least one orthogonal frequency division multiplexing (OFDM) symbol, wherein the duplicated data is allocated after the part of original data; and   transmitting the original data and the duplicate data,   wherein the original data are transmitted through contiguous subcarriers corresponding to first frequency values and the duplicate data are transmitted through contiguous subcarriers corresponding to second frequency values, 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 original data and the duplicate data is one of 0, π/2, π/4 and π/6. 
     
     
       9. The method of claim 7, wherein the method further includes: changing a size of the duplicate data. 
     
     
       10. An apparatus of transmitting data in a wireless communication system, the apparatus comprising:
 a data processing unit for generating duplicate data based on a repetition of a part of original data, the duplicate data being the same as the part of original data, wherein a specific sequence is applied to the duplicate data;   a data change unit for disposing the original data and the duplicate data in a time domain, wherein the original data and the duplicate data are allocated to subcarriers in at least one orthogonal frequency division multiplexing (OFDM) symbol, wherein the duplicated data is allocated after the part of original data; and   a transmitting unit for transmitting the original data and the duplicate data,   wherein the original data are transmitted through contiguous subcarriers corresponding to first frequency values and the duplicate data are transmitted through contiguous subcarriers corresponding to second frequency values, wherein the first frequency values and the second frequency values are different in a frequency domain.   
     
     
       11. The apparatus of claim 10, wherein a phase difference between the original data and the duplicate data is one of 0, π/2, π/4 and π/6. 
     
     
       12. The apparatus of claim 10, wherein the method further includes:
 changing a size of the duplicate data.