CELL SEARCHING METHOD AND APPARATUS IN MULTI-CARRIER SYSTEM

• US 20120093021A1
• Filed: 07/21/2010
• Published: 04/19/2012
• Est. Priority Date: 06/19/2009
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, So Yeon, Cho, Han Gyu, Chung, Jae Hoon, Moon, Sung Ho, Han, Seung Hee, Kwon, Yeong Hyeon
• Granted Patent: US 8,509,110 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04J 13/0029 Gold
• CPC Class Codes: H04J 13/0062 Zadoff-Chu
• CPC Class Codes: H04L 25/023 with extension to other symbols
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2656 Frame synchronisation, e.g. packet synchronisation, time division duplex [TDD] switching point detection or subframe synchronisation
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information

Abstract

Provided are a cell searching method and an apparatus in a multi-carrier system. A terminal acquires a first physical cell identity (PCI) for a first downlink component carrier, and acquires an expanded PCI for a second downlink component carrier. A first downlink reference signal through the first downlink element carrier is transmitted on the basis of the PCI, and a second downlink reference signal through the second downlink component carrier is transmitted on the basis of the expanded PCI.

Claims

1. A cell search method in a multiple carrier system, comprising:

obtaining a first physical cell identity (PCI) for a first downlink component carrier, and

obtaining an extended PCI for a second downlink component carrier,

wherein a first downlink reference signal through the first downlink component carrier is transmitted based on the PCI, and a second downlink reference signal through the second downlink component carrier is transmitted based on the extended PCI.

2. The method of claim 1, wherein the extended PCI is obtained based on a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) on the second downlink component carrier.

3. The method of claim 2, wherein the first PCI is obtained in a range of 0 to 503, and the extended PCI has a value greater than 503.

4. The method of claim 1, wherein obtaining the extended PCI comprises:

obtaining a second PCI for the second downlink component carrier based on a PSS and a SSS on the second downlink component carrier, and

obtaining the extended PCI based on the second PCI.

5. The method of claim 4, wherein the extended PCI is a value in which an offset has been added to the second PCI.

6. The method of claim 4, wherein the first PCI and the second PCI are same.

7. The method of claim 1, wherein the extended PCI is a value in which an offset has been added to the first PCI.

8. The method of claim 1, wherein the extended PCI is used to transmit a reference signal of an uplink carrier linked to the second downlink component carrier.

9. The method of claim 1, wherein the extended PCI is used to transmit an uplink channel of an uplink carrier linked to the second downlink component carrier.

10. A user equipment for performing a cell search in a multiple carrier system, comprising:

a radio frequency (RF) unit configured to transmit and receive radio signals; and

a processor coupled to the RF unit and configured to perform the cell search,

wherein the processor is configured to;

obtain a first physical cell identity (PCI) for a first downlink component carrier, and

obtain an extended PCI for a second downlink component carrier,

wherein a first downlink reference signal through the first downlink component carrier is transmitted based on the PCI, and a second downlink reference signal through the second downlink component carrier is transmitted based on the extended PCI.

11. The user equipment of claim 10, wherein the extended PCI is obtained based on a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) on the second downlink component carrier.

12. The user equipment of claim 11, wherein the first PCI is obtained in a range of 0 to 503, and the extended PCI has a value greater than 503.

13. The user equipment of claim 10, wherein the processor is configured to obtain a second PCI for the second downlink component carrier based on a PSS and a SSS on the second downlink component carrier and obtains the extended PCI based on the second PCI.

14. The user equipment of claim 13, wherein the extended PCI is a value in which an offset has been added to the second PCI.

15. The user equipment of claim 13, wherein the first PCI and the second PCI are identical with each other.

16. The user equipment of claim 10, wherein the extended PCI is a value in which an offset has been added to the first PCI.

17. The user equipment of claim 10, wherein the extended PCI is used to transmit a reference signal of an uplink carrier linked to the second downlink component carrier.

18. The user equipment of claim 10, wherein the extended PCI is used to transmit an uplink channel of an uplink carrier linked to the second downlink component carrier.