METHODS AND PROCEDURES FOR HIGH SPEED UE ACCESS

• US 20080194259A1
• Filed: 12/17/2007
• Published: 08/14/2008
• Est. Priority Date: 02/12/2007
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Vujcic, Dragan, Kwon, Yeongn Hyeon
• Granted Patent: US 8,787,957 B2
• Time in Patent Office: Days
• US Class Current: 455/435.1
• CPC Class Codes: H04J 13/0062 Zadoff-Chu
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access

Abstract

A terminal random access procedure is improved by allowing a mobile terminal to correctly map signature indexes onto cyclic shifted Zadoff-Chu (ZC) sequences when the deployed cells support a high-speed mobility by informing a mobile terminal whether a cell supports high-speed mobility.

Claims

1. A method of establishing a communication link between a mobile terminal and a network, the method comprising:

receiving an indication of whether a communication cell supports high-speed mobility;

generating sequences corresponding to signatures available for random access; and

requesting access to the network using a selected one of the generated sequences,

wherein either the sequences are generated according to whether high-speed mobility is supported or the generated sequence is selected according to whether high-speed mobility is supported.

2. The method of claim 1, wherein the generated sequences are cyclic shifted Zadoff-Chu (ZC) sequences and further comprising mapping allowable signatures onto the cyclic shifted ZC sequences.

3. The method of claim 2, wherein each available random access signature is mapped onto a cyclic shifted ZC sequence using all possible cyclic shifted ZC sequences if high mobility is not supported.

4. The method of claim 2, wherein each available random access signature is mapped onto a cyclic shifted ZC sequence using a restricted set of all possible sequences, the restricted set determined according to a sequence index.

5. A method of establishing a communication link between a mobile terminal and a network, the method comprising:

generating sequences corresponding to signatures available for random access, the sequences generated according to a process that either supports high mobility or does not support high-speed mobility;

transmitting an indication of whether a cell supports high-speed mobility;

receiving an access request from a mobile terminal, the access request using a selected one of the generated sequences; and

correlating the received request to each of the generated sequences in order to determine which of the generated sequences was used by the mobile terminal.

6. The method of claim 5, wherein the generated sequences are cyclic shifted Zadoff-Chu (ZC) sequences and further comprising mapping allowable signatures onto the cyclic shifted ZC sequences.

7. The method of claim 6, wherein each available random access signature is mapped onto a cyclic shifted ZC sequence using all possible cyclic shifted ZC sequences if high-speed mobility is not supported.

8. The method of claim 6, wherein each available random access signature is mapped onto a cyclic shifted ZC sequence using a restricted set of all possible sequences, the restricted set determined according to a sequence index.

9. A method of establishing a communication link between a mobile terminal and a network, the method comprising:

receiving an indication of whether a cell supports high-speed mobility; and

requesting access to the network using the indication,

wherein the indication indicates information on restricted use of cyclic shifts.

10. The method of claim 9, wherein the indication comprises one bit.

11. The method of claim 9, wherein requesting access to the network comprises:

generating sequences corresponding to signatures available for random access; and

requesting access to the network using a selected one of the generated sequences,

wherein either the sequences are generated according whether high-speed mobility is supported or the generated sequence is selected according to whether high-speed mobility is supported.

12. The method of claim 11, wherein the generated sequences are cyclic shifted Zadoff-Chu (ZC) sequences and further comprising mapping allowable signatures onto the cyclic shifted ZC sequences, each available random access signature mapped onto a cyclic shifted ZC sequence using a restricted set of all possible sequences, the restricted set determined according to the indication.

13. A method of establishing a communication link between a mobile terminal and a network, the method comprising:

transmitting an indication of whether a cell supports high-speed mobility; and

receiving a request to access the network from the mobile terminal,

wherein the indication indicates information on restricted use of cyclic shifts and the request is based on the indication.

14. The method of claim 13, wherein the indication comprises one bit.

15. The method of claim 13, further comprising:

generating sequences corresponding to signatures available for random access, the sequences generated according to a process that either supports high mobility or does not support high-speed mobility;

receiving the access request from the mobile terminal, the access request using a selected one of the generated sequences; and

correlating the received request to each of the generated sequences in order to determine which of the generated sequences was used by the mobile terminal.

16. The method of claim 15, wherein the generated sequences are cyclic shifted Zadoff-Chu (ZC) sequences and further comprising mapping allowable signatures onto the cyclic shifted ZC sequences, each available random access signature mapped onto a cyclic shifted ZC sequence using a restricted set of all possible sequences, the restricted set determined according to the indication.

17. A mobile terminal for of establishing a communication link with a network, the mobile terminal comprising:

a transmitting/receiving unit transmitting and receiving messages between the mobile terminal and the network;

a display unit displaying user interface information;

an input unit receiving inputs from a user; and

a processing unit processing a received indication of whether a communication cell supports high-speed mobility, generating sequences corresponding to signatures available for random access and controlling the transmitting/receiving unit to request access to the network using a selected one of the generated sequences,

wherein the processing unit either generates the sequences according to whether high-speed mobility is supported or the selects the generated sequence according to whether high-speed mobility is supported.

18. The mobile terminal of claim 17, wherein the generated sequences are cyclic shifted Zadoff-Chu (ZC) sequences and the processing unit further maps allowable signatures onto the cyclic shifted ZC sequences.

19. The mobile terminal of claim 18, wherein the processing unit maps each available random access signature onto a cyclic shifted ZC sequence using all possible cyclic shifted ZC sequences if high mobility is not supported.

20. The mobile terminal of claim 18, wherein the processing unit maps each available random access signature onto a cyclic shifted ZC sequence using a restricted set of all possible sequences, the restricted set determined according to a sequence index.

21. A mobile terminal for of establishing a communication link with a network, the mobile terminal comprising:

a transmitting/receiving unit transmitting and receiving messages between the mobile terminal and the network;

a display unit displaying user interface information;

an input unit receiving inputs from a user; and

a processing unit processing a received indication of whether a cell supports high-speed mobility and controlling the transmitting/receiving unit to request access to the network using the indication,

wherein the indication indicates information on restricted use of cyclic shifts.

22. The mobile terminal of claim 21, wherein the indication comprises one bit.

23. The mobile terminal of claim 21, wherein processing unit controls the transmitting/receiving unit to request access to the network by:

generating sequences corresponding to signatures available for random access; and

requests access to the network using a selected one of the generated sequences,

wherein the processing unit either generates the sequences according to whether high-speed mobility is supported or the selects the generated sequence according to whether high-speed mobility is supported.

24. The mobile terminal of claim 23, wherein the generated sequences are cyclic shifted Zadoff-Chu (ZC) sequences and the processing unit maps allowable signatures onto the cyclic shifted ZC sequences, each available random access signature mapped onto a cyclic shifted ZC sequence using a restricted set of all possible sequences, the restricted set determined according to the indication.

25. A network for establishing a communication link with a mobile terminal, the network comprising:

a transmitter transmitting messages to the mobile terminal;

a receiver receiving messages from the mobile terminal; and

a controller generating sequences corresponding to signatures available for random access, controlling the transmitter to transmit an indication of whether high-speed mobility is supported, processing a received access request from a mobile terminal that uses a selected one of the generated sequences, and correlating the received request to each of the generated sequences in order to determine which of the generated sequences was used by the mobile terminal,

wherein the controller generates the sequences according to a process that either supports high mobility or does not support high-speed mobility.

26. The network of claim 25, wherein the generated sequences are cyclic shifted Zadoff-Chu (ZC) sequences and the controller maps allowable signatures onto the cyclic shifted ZC sequences.

27. The network of claim 26, wherein the controller maps each available random access signature onto a cyclic shifted ZC sequence using all possible cyclic shifted ZC sequences if high-speed mobility is not supported.

28. The network of claim 26, wherein the controller maps each available random access signature onto a cyclic shifted ZC sequence using a restricted set of all possible sequences, the restricted set determined according to a sequence index.

29. A network for establishing a communication link with a mobile terminal, the network comprising:

a transmitter transmitting messages to the mobile terminal;

a receiver receiving messages from the mobile terminal; and

a controller controlling the transmitter to transmit an indication of whether a cell supports high-speed mobility and processing a received request to access the network from the mobile terminal,

wherein the indication indicates information on restricted use of cyclic shifts and the access request is based on the indication.

30. The network of claim 29, wherein the indication comprises one bit.

31. The network of claim 29, wherein the controller further:

generates sequences corresponding to signatures available for random access, the sequences generated according to a process that either supports high mobility or does not support high-speed mobility; and

correlates that received access request to each of the generated sequences in order to determine which of the generated sequences the mobile terminal used when sending the access request.

32. The network of claim 31, wherein the generated sequences are cyclic shifted Zadoff-Chu (ZC) sequences and the controller maps allowable signatures onto the cyclic shifted ZC sequences, each available random access signature mapped onto a cyclic shifted ZC sequence using a restricted set of all possible sequences, the restricted set determined according to the indication.