APPARATUS AND METHOD FOR TRANSMITTING DATA USING A PLURALITY OF CARRIERS

• US 20090219802A1
• Filed: 11/10/2006
• Published: 09/03/2009
• Est. Priority Date: 11/10/2005
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Dong Cheol, Noh, Min Seok, Han, Seung Hee, Park, Hyun Hwa, Kwon, Yeong Hyeon, Lee, Hyun Woo
• Granted Patent: US 8,804,478 B2
• Time in Patent Office: Days
• US Class Current: 370/210
• CPC Class Codes: H04B 1/70735 Code identification H04B1/7083 takes precedence
• CPC Class Codes: H04J 11/0073 Acquisition of primary synchronisation channel, e.g. detection of cell-ID within cell-ID group
• CPC Class Codes: H04J 11/0076 Acquisition of secondary synchronisation channel, e.g. detection of cell-ID group
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/26132 using repetition
• CPC Class Codes: H04L 27/2636 with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others

Abstract

The present invention relates to a data transceiving method in a communication system based on a plurality of carriers, and more particularly, to a method of designing a sequence in a communication system using orthogonal subcarriers. The present invention includes the steps of generating a time-domain sequence with a specific length in a time domain, generating a frequency-domain sequence by performing a DFT or FFT operation on the time-domain sequence according to a length of the generated sequence, including a DC subcarrier and a guard subcarrier in the frequency-domain sequence, and performing an IDFT or IFFT operation on the frequency-domain sequence including the DC subcarrier and the guard subcarrier.

Claims

1. A method of transmitting data using a plurality of carriers in a communication system, comprising the steps of:

generating a time-domain sequence with a length in a time domain;

generating a frequency-domain sequence by performing a DFT or FFT operation on the time-domain sequence according to the length of the generated sequence;

including a DC subcarrier and at least one guard subcarrier in the frequency-domain sequence; and

performing an IDFT or IFFT operation on the frequency-domain sequence including the DC subcarrier and the at least one guard subcarrier.

2. The method of claim 1, wherein if the length of the time-domain sequence (a_n) is N and if M is a natural number as a relative prime number with the N, the time-domain sequence (a_n) is generated by

$$

a n = 

( 



M 



π





n 2 N ) ,

when N is even and

$<br><br>a_n={\mathrm{<br><br>}}^{\left(\mathrm{<br><br>}<br><br>\frac{M<br><br><br><br>\mathrm{\pi <br><br>}<br><br><br><br>n<br><br>\left(n+1\right)}{N}\right)},$

when N is odd.

3. The method of claim 1, wherein the time-domain sequence is generated by repeating specific subsequencies.

4. The method of claim 1, further comprising the step of applying a PAPR reducing scheme to the frequency-domain sequence including the DC subcarrier and the at least one guard subcarrier.

5. An apparatus for transmitting data using a plurality of carriers, comprising:

a sequence generating module generating a time-domain sequence with a length in a time domain;

a frequency transforming module generating a frequency-domain sequence by performing a DFT or FFT operation on the time-domain sequence according to the length of the generated sequence;

a data inserting module enabling a DC subcarrier and at least one guard subcarrier to be included in the frequency-domain frequency; and

a module performing an IDFT or IFFT operation on the frequency-domain sequence including the DC subcarrier and the at least one guard subcarrier.

6. The apparatus of claim 5, wherein if the length of the time-domain sequence (a_n) is N and if M is a natural number as a relative prime number with the N, the sequence generating module generates the time-domain sequence (a_n) by

$$

a n = 

( 



M 



π





n 2 N ) ,

when N is even and

$a_n={\mathrm{<br><br>}}^{\left(\mathrm{<br><br>}<br><br>\frac{M<br><br><br><br>\mathrm{\pi <br><br>}<br><br><br><br>n<br><br>\left(n+1\right)}{N}\right)},$

when N is odd.

7. The apparatus of claim 5, wherein the time-domain sequence is generated by repeating specific subsequencies.

8. The apparatus of claim 5, further comprising a PAPR reducing module applying a PAPR reducing scheme to the frequency-domain sequence including the DC subcarrier and the at least one guard subcarrier.

9. A method of transmitting data using a plurality of carriers in a communication system, comprising the steps of:

generating a second sequence by repeating a first sequence in time domain;

transforming the generated second sequence into a frequency-domain sequence using a DFT or FFT operation;

performing a data processing on the frequency-domain sequence to allocate a null to a DC subcarrier; and

transforming the data-processed frequency-domain sequence into a time-domain sequence by performing an IDFT or IFFT operation on.

10. The method of claim 9, wherein the first sequence is a Frank sequence.

11. The method of claim 10, wherein a length of the Frank sequence is 36.

12. The method of claim 9, wherein in the data processing performing step, a sequence value corresponding to the DC subcarrier is processed into 0.

13. The method of claim 9, wherein in the data processing performing step, a circular shift is performed on the frequency-domain sequence.

14. The method of claim 9, wherein the time-domain sequence transformed by the IFFT or IDFT operation corresponds to a primary synchronous channel (P-SCH) for synchronization detection.

15. The method of claim 9, wherein a length of the time-domain sequence transformed by the IFFT or IDFT operation is 72.