APPARATUS AND METHOD FOR SYNCHRONIZING AND OBTAINING SYSTEM INFORMATION IN WIRELESS COMMUNICATION SYSTEM

• US 20130064239A1
• Filed: 09/07/2012
• Published: 03/14/2013
• Est. Priority Date: 09/09/2011
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Yu, Hyun-Kyu, Kim, Tae-Young, Cho, Jae-Weon
• Granted Patent: US 9,894,624 B2
• Time in Patent Office: Days
• US Class Current: 370/350
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams

Abstract

A base station and terminal use methods of obtaining synchronization and system information in a wireless communication system. An operation of a base station includes generating a synchronization signal to be transmitted through a Synchronization Channel (SCH), generating a broadcast signal to be transmitted through a Broadcast Channel (BCH), and transmitting repetitively the SCH and the BCH by performing beamforming on the channels with different transmission beams.

Claims

1. A method of operating a base station in a wireless communication system, the method comprising:

generating a synchronization signal to be transmitted through a Synchronization Channel (SCH);

generating a broadcast signal to be transmitted through a Broadcast Channel (BCH); and

transmitting repetitively the SCH and the BCH by performing beamforming on the channels with different transmission beams.

2. The method of claim 1, wherein the synchronization signal indicates at least one of a cell identifier (ID) and a transmission beam ID applied to the synchronization signal.

3. The method of claim 2, wherein at least one of the cell ID and the transmission beam ID applied to the synchronization signal is indicated by using at least one of:

a sequence which constitutes the synchronization signal, a position of a subcarrier to which the synchronization signal is mapped, a scrambling code for the synchronization signal, and a covering code.

4. The method of claim 1, wherein the broadcast signal indicates a transmission beam ID applied to the broadcast signal.

5. The method of claim 4, wherein the transmission beam ID is indicated by using at least one of an information item included in the system information and a scrambling code applied to the system information.

6. The method of claim 1, wherein the repetitively transmitting of the SCH and the BCH comprises:

forming a transmission beam for a first antenna area by using a first antenna group among a plurality of antenna groups allocated respectively to a plurality of antenna areas included in one cell; and

forming a transmission beam for a second antenna area by using a second antenna group among the plurality of antenna groups.

7. The method of claim 6, wherein the repetitively transmitting of the SCH and the BCH comprises forming simultaneously a transmission beam for the first antenna area and a transmission beam for the second antenna area.

8. The method of claim 6, wherein the synchronization signal indicates an antenna area ID of an antenna area corresponding to an antenna group which transmits the synchronization signal.

9. A method of operating a terminal in a wireless communication system, the method comprising:

detecting at least one of Synchronization Channels (SCHs) repetitively transmitted by being beam-formed with different transmission beams; and

obtaining system information by using at least one of Broadcast Channels (BCHs) repetitively transmitted by being beam-formed with different transmission beams.

10. The method of claim 9, wherein a synchronization signal received through the SCHs indicates at least one of a cell ID and a transmission beam ID applied to the synchronization signal.

11. The method of claim 10, wherein at least one of the cell ID and the transmission beam ID applied to the synchronization signal is indicated by using at least one of:

a sequence which constitutes the synchronization signal, a position of a subcarrier to which the synchronization signal is mapped, a scrambling code for the synchronization signal, and a covering code.

12. The method of claim 9, wherein a broadcast signal received through the BCH indicates a transmission beam ID applied to the broadcast signal.

13. The method of claim 12, wherein the transmission beam ID is indicated by using at least one of an information item included in the system information and a scrambling code applied to the system information.

14. The method of claim 9, wherein the obtaining of the system information through at least one of the BCHs comprises:

combining broadcast signals received through at least two of the BCHs; and

decoding the combined broadcast signals.

15. The method of claim 9, further comprising obtaining frame synchronization by using the system information.

16. The method of claim 15, wherein the obtaining of the frame synchronization comprises:

determining a boundary of a period in which the SCHs and the BCHs are repetitively transmitted by using the system information; and

determining a boundary of the frame from the boundary of the period.

17. The method of claim 16, wherein the determining of the boundary of the period in which the SCHs and the BCHs are repetitively transmitted by using the system information comprises:

determining the number of SCHs transmitted from a base station by using the system information; and

calculating the number of SCHs located subsequent to the detected SCH by using the number of transmission beams.

18. The method of claim 9, wherein the detecting of the at least one of SCHs repetitively transmitted by being beam-formed with the different transmission beams comprises:

detecting SCHs which are beam-formed with the same transmission beam by applying different reception beams; and

determining a combination of a preferred transmission beam and a preferred reception beam which minimize reception signal strength.

19. A base station apparatus in a wireless communication system, the apparatus comprising:

a modem configured to generate a synchronization signal to be transmitted through a Synchronization Channel (SCH) and generate a broadcast signal to be transmitted through a Broadcast Channel (BCH);

a beamforming unit configured to perform beamforming on the SCH and the BCH with different transmission beams; and

a controller configured to transmit repetitively the SCH and the BCH which are beam-formed with the different transmission beams.

20. The apparatus of claim 19, wherein the synchronization signal indicates at least one of a cell ID and a transmission beam ID applied to the synchronization signal.

21. The apparatus of claim 20, wherein at least one of the cell ID and the transmission beam ID applied to the synchronization signal is indicated by using at least one of;

a sequence which constitutes the synchronization signal, a position of a subcarrier to which the synchronization signal is mapped, a scrambling code for the synchronization signal, and a covering code.

22. The apparatus of claim 19, wherein the broadcast signal indicates a transmission beam ID applied to the broadcast signal.

23. The apparatus of claim 22, wherein the transmission beam ID is indicated by using at least one of an information item included in the system information and a scrambling code applied to the system information.

24. The apparatus of claim 19, wherein the controller is configured to form a transmission beam for a first antenna area by using a first antenna group among a plurality of antenna groups allocated respectively to a plurality of antenna areas included in one cell, and form a transmission beam for a second antenna area by using a second antenna group among the plurality of antenna groups.

25. The apparatus of claim 24, wherein the controller is configured to form simultaneously a transmission beam for the first antenna area and a transmission beam for the second antenna area.

26. The apparatus of claim 24, wherein the synchronization signal indicates an antenna area ID of an antenna area corresponding to an antenna group which transmits the synchronization signal.

27. A terminal apparatus in a wireless communication system, the apparatus comprising:

a modem configured to detect at least one of Synchronization Channels (SCHs) repetitively transmitted by being beam-formed with different transmission beams; and

a controller configured to obtain system information by using at least one of Broadcast Channels (BCHs) repetitively transmitted by being beam-formed with different transmission beams.

28. The apparatus of claim 27, wherein a synchronization signal received through the SCHs indicates at least one of a cell ID and a transmission beam ID applied to the synchronization signal.

29. The apparatus of claim 28, wherein at least one of the cell ID and the transmission beam ID applied to the synchronization signal is indicated by using at least one of:

a sequence which constitutes the synchronization signal, a position of a subcarrier to which the synchronization signal is mapped, a scrambling code for the synchronization signal, and a covering code.

30. The apparatus of claim 27, wherein a broadcast signal received through the BCH indicates a transmission beam ID applied to the broadcast signal.

31. The apparatus of claim 30, wherein the transmission beam ID is indicated by using at least one of an information item included in the system information and a scrambling code applied to the system information.

32. The apparatus of claim 27, wherein the modem is configured to combine broadcast signals received through at least two of the BCHs, and decode the combined broadcast signals.

33. The apparatus of claim 27, wherein the controller is configured to obtain frame synchronization by using the system information.

34. The apparatus of claim 33, wherein the controller is configured to determine a boundary of a period in which the SCHs and the BCHs are repetitively transmitted by using the system information, and determine a boundary of the frame from the boundary of the period.

35. The apparatus of claim 34, wherein the controller is configured to determine the number of SCHs transmitted from a base station by using the system information, and calculate the number of SCHs located subsequent to the detected SCH by using the number of transmission beams.

36. The apparatus of claim 27, further comprising a beamforming unit configured to apply different reception beams to SCHs which are beam-formed with the same transmission beam, wherein the controller is configured to determine a combination of a preferred transmission beam and a preferred reception beam which minimize reception signal strength.