Apparatus and method for synchronization acquisition and cell ID search in wireless communication system

1. A method for transmitting a synchronization signal of a base station (BS) in a wireless communication system, the method comprising:

using a binary frequency-domain preamble sequence predetermined for cell ID search and a binary time-domain preamble sequence predetermined for synchronization acquisition to determine a complex time-domain preamble sequence according to an Inverse Fast Fourier Transform (IFFT) operation on the binary frequency-domain preamble sequence; and

transmitting the complex time-domain preamble sequence and the binary time-domain preamble sequence to a mobile station (MS).

2. The method of claim 1 , wherein the synchronization acquisition and the cell ID search are performed using an Orthogonal Frequency Division Multiplexing (OFDM) symbol.

3. The method of claim 1 , wherein the input value of the IFFT operation includes the binary frequency-domain preamble sequence and the complex frequency-domain preamble sequence used to generate the binary time-domain preamble sequence and the complex time-domain preamble sequence according to the IFFT operation.

4. The method of claim 1 , wherein the complex time-domain preamble sequence is determined except the binary time-domain preamble sequence among the time-domain preamble sequences that are generated.

5. The method of claim 1 , wherein using comprises determining the complex time-domain preamble sequence based on a first equation defined as:

s U =( D 12 ) −1 ( p D −D 11 s D )

Where s U is the complex time-domain preamble sequence, D 12 is a (1, 2) element of a discrete Fourier transform matrix D defining the relationship between a frequency-domain sequence and time-domain sequence, p D is a binary frequency-domain preamble sequence, D 11 is a (1, 1) element of a discrete Fourier transform matrix D defining the relationship between a frequency-domain sequence and time-domain sequence, and s D is a binary time-domain preamble sequence.

6. The method of claim 5 , wherein D is defined based on a second equation defined as:

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7. The method of claim 6 , wherein p is based on a third equation defined as:

p

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p

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8. A method for acquiring the synchronization and cell ID of a mobile station (MS) in a wireless communication system, comprising:

receiving a signal and extracting a portion of the received signal, performing a correlation operation on the portion of the received signal and a binary time-domain preamble sequence predetermined for synchronization acquisition;

detecting a peak value of the correlation operation result to acquire synchronization;

performing a Fast Fourier Transform (FFT) operation on a preamble sequence with an FFT size from the peak value detection point to transform the preamble sequence into a frequency-domain preamble sequence;

extracting a portion of the frequency-domain preamble sequence,

performing a correlation operation on the portion of the frequency-domain preamble sequence and the binary frequency-domain preamble sequence predetermined for cell ID search; and

detecting a peak value of the correlation operation result on the binary frequency-domain preamble sequence to acquire a cell ID.

9. The method of claim 8 , wherein the synchronization acquisition and the cell ID search are performed using an Orthogonal Frequency Division Multiplexing (OFDM) symbol.

10. The method of claim 8 , wherein the received signal has a size equal to a size of the binary time-domain preamble sequence predetermined for synchronization acquisition.

11. The method of claim 8 , wherein the extracted portion of the frequency-domain preamble sequence has a size equal to a size of a binary frequency-domain preamble sequence predetermined for cell ID search.

12. An apparatus for transmitting a synchronization signal of a base station (BS) in a wireless communication system, the apparatus comprising:

an Inverse Fast Fourier Transform (IFFT) operator using a binary frequency-domain preamble sequence predetermined for cell ID search and a binary time-domain preamble sequence predetermined for synchronization acquisition, to determine a complex time-domain preamble sequence according to an IFFT operation on the binary frequency-domain preamble sequence; and

a Radio Frequency (RF) transmitter transmitting the complex time-domain preamble sequence and the binary time-domain preamble sequence to a mobile station (MS).

13. The apparatus of claim 12 , wherein the synchronization acquisition and the cell ID search are performed using an Orthogonal Frequency Division Multiplexing (OFDM) symbol.

14. The apparatus of claim 12 , wherein the input value of the IFFT operation includes the binary frequency-domain preamble sequence and the complex frequency-domain preamble sequence used to generate the binary time-domain preamble sequence and the complex time-domain preamble sequence according to the IFFT operation.

15. The apparatus of claim 12 , wherein the complex time-domain preamble sequence is determined except the binary time-domain preamble sequence among the time-domain preamble sequences that are generated.

16. The apparatus of claim 12 , wherein using comprises determining the complex time-domain preamble sequence based on a first equation defined as:

s U =( D 12 ) −1 ( p D −D 11 s D )

Where s U is the complex time-domain preamble sequence, D 12 is a (1, 2) element of a discrete Fourier transform matrix D defining the relationship between a frequency-domain sequence and time-domain sequence, p D is a binary frequency-domain preamble sequence, D 11 is a (1, 1) element of a discrete Fourier transform matrix D defining the relationship between a frequency-domain sequence and time-domain sequence, and s D is a binary time-domain preamble sequence.

17. The apparatus of claim 16 , wherein D is defined based on a second equation defined as:

D

=

1

N

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1

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1

1

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2

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18. The apparatus of claim 17 , wherein p is based on a third equation defined as:

p

=

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[

p

D

p

U

]

=

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[

D

11

D

12

D

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D

22

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s

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s

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+

D

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s

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s

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22

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s

U

]

.

19. An apparatus for acquiring the synchronization and cell ID of a mobile station (MS) in a wireless communication system, comprising:

a Radio Frequency (RF) receiver receiving a signal;

a synchronization acquirer extracting a portion of the received signal, which has the same size as a binary time-domain preamble sequence predetermined for synchronization acquisition, performing a correlation operation on the portion of the received signal and the binary time-domain preamble sequence predetermined for synchronization acquisition, and detecting a peak value of the correlation operation result to acquire synchronization;

a Fast Fourier Transform (FFT) operator performing an FFT operation on a preamble sequence with an FFT size from the peak value detection point to transform the preamble sequence into a frequency-domain preamble sequence; and

a cell ID acquirer extracting a portion of the frequency-domain preamble sequence, which has the same size as a binary frequency-domain preamble sequence predetermined for cell ID search, performing a correlation operation on the portion of the frequency-domain preamble sequence and the binary frequency-domain preamble sequence predetermined for cell ID search, and detecting a peak value of the correlation operation result on the binary frequency-domain preamble sequence to acquire a cell ID.

20. The apparatus of claim 19 , wherein the synchronization acquisition and the cell ID search are performed using an Orthogonal Frequency Division Multiplexing (OFDM) symbol.