Method and apparatus for transmitting and receiving broadcast channel in cellular communication system

1. A method for transmitting a signal of a Broadcast Channel (BCH) in a cellular communication system, the method comprising:

repeating, by a transmitter, symbols comprising information about the BCH;

masking, by the transmitter, the repeated symbols with at least one code selected from a given code set based on a number of repetitions of the symbols and a beam index indicating a beam for transmission of the BCH;

subcarrier-mapping, by the transmitter, the masked symbols; and

transmitting, by the transmitter, the subcarrier-mapped symbols by using the beam corresponding to the selected at least one code.

2. The method of claim 1 , wherein the at least one code is selected from the given code set according to a predefined rule based on a cell identifier of a cell in which the BCH is transmitted and the beam index used in transmission of the BCH.

3. The method of claim 1 , wherein the subcarrier-mapped symbols are transmitted in a plurality of regions that are separated at equal intervals in a frame by using different beams for the plurality of regions.

4. The method of claim 1 , wherein the subcarrier-mapped symbols are transmitted in a plurality of consecutive regions of a forepart of a frame by using different beams for the plurality of consecutive regions.

5. The method of claim 1 , wherein the at least one code is selected by a code index calculated using:

Code c =(IDcell+ w )mod R,

wherein c indicates the code index, IDcell indicates a cell index of a cell in which the BCH is transmitted, w indicates a beam index used for the BCH, and R indicates a number of repetitions of the symbols.

6. The method of claim 1 , wherein the given code set comprises a plurality of Walsh Hadamard codes.

7. The method of claim 1 , wherein a number of repetitions of the symbols is determined by one or more of a structure of a base station that transmits the BCH and a total number of antenna devices available for the BCH.

8. The method of claim 1 , wherein a number of repetitions of the symbols is determined by a number of transmission beams available for the BCH.

9. The method of claim 1 , wherein the subcarrier-mapping of the masked symbols comprises mapping symbols corresponding to repetitions of one symbol to adjacent frequency tones or time symbols.

10. A method for receiving a signal of a Broadcast Channel (BCH) in a cellular communication system, the method comprising:

configuring, by a receiver, a reception vector comprising a predetermined number of symbols that comprise information about the BCH based on a reception signal received from a transmitter;

detecting, by the receiver, at least one code of a given code set, which is applied to masking of the symbols, from the reception vector;

detecting, by the receiver, a beam index indicating a beam used for transmission of the BCH, based on a code index of the at least one detected code; and

determining, by the receiver, a boundary of a frame used in communication between the transmitter and the receiver, based on the beam index.

11. The method of claim 10 , wherein the beam index is detected based on the code index, a number of repeated symbols that form the reception vector, and a cell identifier of a cell in which the BCH is transmitted.

12. The method of claim 10 , wherein the reception vector is transmitted in a plurality of regions that are separated at equal intervals in the frame by using different beams for the plurality of regions.

13. The method of claim 10 , wherein the reception vector is transmitted in a plurality of consecutive regions of a forepart of the frame by using different beams for the plurality of consecutive regions.

14. The method of claim 10 , wherein the beam index is calculated using:

Code c =(IDcell+ w )mod R,

wherein c indicates the code index, IDcell indicates a cell index of a cell in which the BCH is transmitted, w indicates a beam index used for the BCH, and R indicates a number of repeated symbols of the reception vector.

15. The method of claim 10 , wherein the given code set comprises a plurality of Walsh Hadamard codes.

16. The method of claim 10 , wherein a number of repeated symbols of the reception vector is determined by one or more of a structure of a base station that transmits the BCH and a total number of antenna devices available for the BCH.

17. The method of claim 10 , wherein a number of repeated symbols of the reception vector is determined by a number of transmission beams available for the BCH in a base station that transmits the BCH.

18. The method of claim 10 , wherein a number of the repeated symbols of the reception vector is obtained from a Synchronization Channel (SCH) transmitted from a base station.

19. An apparatus for transmitting a Broadcast Channel (BCH) in a cellular communication system, the apparatus comprising:

a memory element; and

a controller coupled to the memory element, the controller configured to control:

repeat symbols comprising information about the BCH;

mask the repeated symbols with at least one code selected from a given code set based on a number of repetitions of the symbols and a beam index indicating a beam for transmission of the BCH;

subcarrier-map the masked symbols; and

a transmitter configured to transmit the subcarrier-mapped symbols by using the beam corresponding to the at least one selected code.

20. The apparatus of claim 19 , wherein the at least one code is selected from the given code set according to a predefined rule based on a cell identifier of a cell in which the BCH is transmitted and the beam index used in the BCH.

21. The apparatus of claim 19 , wherein the subcarrier-mapped symbols are transmitted in a plurality of regions that are separated at equal intervals in a frame by using different beams for the plurality of regions.

22. The apparatus of claim 19 , wherein the subcarrier-mapped symbols are transmitted in a plurality of consecutive regions of a forepart of a frame by using different beams for the plurality of consecutive regions.

23. The apparatus of claim 19 , wherein the at least one code is selected by a code index calculated using:

Code c =(IDcell+ w )mod R,

wherein c indicates the code index, IDcell indicates a cell index of a cell in which the BCH is transmitted, w indicates a beam index used for the BCH, and R indicates a number of repetitions of the symbols.

24. The apparatus of claim 19 , wherein the given code set comprises a plurality of Walsh Hadamard codes.

25. The apparatus of claim 19 , wherein a number of repetitions of the symbols is determined by one or more of a structure of a base station that transmits the BCH and a total number of antenna devices available for the BCH.

26. The apparatus of claim 19 , wherein a number of repetitions of the symbols is determined by a number of transmission beams available for the BCH.

27. The apparatus of claim 19 , wherein the subcarrier-mapper maps symbols corresponding to repetitions of one symbol to adjacent frequency tones or time symbols.

28. An apparatus for receiving a Broadcast Channel (BCH) in a cellular communication system, the apparatus comprising:

a memory element;

a receiver configured to receive a reception signal from a transmitter; and

a controller coupled to the memory element and the receiver, the controller configured to:

configured a reception vector comprising a predetermined number of symbols that comprise information about the BCH based on the reception signal,

detect at least one code of a given code set, which are applied to masking of the symbols, from the reception vector,

detect a beam index indicating a beam used for transmission of the BCH, based on a code index of the at least one detected code, and

determine a boundary of a frame used in communication between the transmitter and the receiver, based on the beam index.

29. The apparatus of claim 28 , wherein the beam index is detected based on the code index, a number of repeated symbols that form the reception vector, and a cell identifier of a cell in which the BCH is transmitted.

30. The apparatus of claim 28 , wherein the reception vector is transmitted in a plurality of regions that are separated at equal intervals in the frame by using different beams for the plurality of regions.

31. The apparatus of claim 28 , wherein the reception vector is transmitted in a plurality of consecutive regions of a forepart of the frame by using different beams for the plurality of consecutive regions.

32. The apparatus of claim 28 , wherein the beam index is calculated using:

Code c =(IDcell+ w )mod R,

wherein c indicates the code index, IDcell indicates a cell index of a cell in which the BCH is transmitted, w indicates a beam index used for the BCH, and R indicates a number of repeated symbols of the reception vector.

33. The apparatus of claim 28 , wherein the given code set comprises a plurality of Walsh Hadamard codes.

34. The apparatus of claim 28 , wherein a number of repeated symbols of the reception vector is determined by one or more of a structure of a base station that transmits the BCH and a total number of antenna devices available for the BCH.

35. The apparatus of claim 28 , wherein a number of repeated symbols of the reception vector is determined by a number of transmission beams available for the BCH in a base station that transmits the BCH.

36. The apparatus of claim 28 , wherein a number of repeated symbols of the reception vector is obtained from a Synchronization Channel (SCH) transmitted from a base station.