METHOD AND APPARATUS FOR RANDOM ACCESS IN AN ORTHOGONAL MULTIPLE-ACCESS COMMUNICATION SYSTEM

• US 20080273610A1
• Filed: 08/20/2007
• Published: 11/06/2008
• Est. Priority Date: 08/21/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Malladi, Durga Prasad, Montojo, Juan, Damnjanovic, Aleksander
• Granted Patent: US 8,295,243 B2
• Time in Patent Office: Days
• US Class Current: 375/260
• CPC Class Codes: H04L 1/0029 Reduction of the amount of signalling, e.g. retention of useful signalling or differential signalling power control H04W52/04
• CPC Class Codes: H04L 1/0032 Without explicit signalling
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 25/03866 using scrambling
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 56/0045 compensating for timing error by altering transmission time
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

Techniques for accessing a wireless communication system are described. A user equipment (UE) sends a random access preamble for system access. The random access preamble may include a random identifier (ID), a channel quality indicator (CQI), etc. The UE may randomly select the random ID or may be assigned this random ID. The UE receives a random access response from a base station. The random access response may include control channel resources (e.g., CQI and PC resources), uplink resources, and/or control information (e.g., timing advance and PC correction) for the UE. The random access response may be sent in two parts using two messages. A first message may be sent on a control channel and may include identification information and possibly other information. A second message may be sent on a shared data channel and may include remaining information for the random access response.

Claims

1. An apparatus for wireless communication, comprising:

at least one processor configured to send a random access preamble for system access by a user equipment (UE), to receive a random access response comprising control channel resources assigned to the UE, and to exchange control information using the assigned control channel resources; and

a memory coupled to the at least one processor.

2. The apparatus of claim 1, wherein the assigned control channel resources comprise at least one of channel quality indicator (CQI) resources used to send CQI on uplink by the UE and power control (PC) resources used to send PC corrections on downlink to the UE.

3. The apparatus of claim 1, wherein the at least one processor is configured to receive a first message for the random access response on a control channel for a shared data channel, and to receive a second message for the random access response on the shared data channel, the first message comprising identification information for the random access preamble, and the second message comprising the control channel resources assigned to the UE.

4. The apparatus of claim 1, wherein the at least one processor is configured to determine the random access preamble based on at least one of a random identifier (ID), a channel quality indicator (CQI), and an access type.

5. The apparatus of claim 1, wherein the at least one processor is configured to receive control information in the random access response, the control information comprising at least one of timing advance and power control (PC) correction.

6. The apparatus of claim 1, wherein the at least one;

processor is configured to receive a Cell Radio Network Temporary Identifier (C-RNTI) in the random access response.

7. The apparatus of claim 1, wherein the at least one processor is configured to receive uplink resources assigned to the UE in the random access response, and to send data using the assigned uplink resources.

8. The apparatus of claim 1, wherein the at least one processor is configured to select an access sequence for the random access preamble from a pool of available access sequences, and to send the selected access sequence to convey the random access preamble.

9. A method for wireless communication, comprising:

sending a random access preamble for system access by a user equipment (UE);

receiving a random access response comprising control channel resources assigned to the UE; and

exchanging control information using the assigned control channel resources.

10. The method of claim 9, further comprising:

receiving at least one of channel quality indicator (CQI) resources and power control (PC) resources for the control channel resources assigned to the UE, the CQI resources being used to send CQI on uplink by the UE, and the PC resources being used to send PC corrections on downlink to the UE.

11. The method of claim 9, wherein the receiving the random access response comprises

receiving a first message for the random access response on a control channel for a shared data channel, the first message comprising identification information for the random access preamble, and

receiving a second message for the random access response on the shared data channel, the second message comprising the control channel resources assigned to the UE.

12. An apparatus for wireless communication, comprising:

means for sending a random access preamble for system access by a user equipment (UE);

means for receiving a random access response comprising control channel resources assigned to the UE; and

means for exchanging control information using the assigned control channel resources.

13. The apparatus of claim 12, further comprising:

means for receiving at least one of channel quality indicator (CQI) resources and power control (PC) resources for the control channel resources assigned to the UE, the CQI resources being used to send CQI on uplink by the UE, and the PC resources being used to send PC corrections on downlink to the UE.

14. The apparatus of claim 12, wherein the means for receiving the random access response comprises

means for receiving a first message for the random access response on a control channel for a shared data channel, the first message comprising identification information for the random access preamble, and

means for receiving a second message for the random access response on the shared data channel, the second message comprising the control channel resources assigned to the UE.

15. A machine-readable medium comprising instructions which, when executed by a machine, cause the machine to perform operations including:

sending a random access preamble for system access by a user equipment (UE);

receiving a random access response comprising control channel resources assigned to the UE; and

exchanging control information using the assigned control channel resources.

16. The machine-readable medium of claim 15 which, when executed by the machine, cause the machine to perform operations further including:

receiving at least one of channel quality indicator (CQI) resources and power control (PC) resources for the control channel resources assigned to the UE, the CQI resources being used to send CQI on uplink by the UE, and the PC resources being used to send PC corrections on downlink to the UE.

17. The machine-readable medium of claim 15 which, when executed by the machine, cause the machine to perform operations further including:

receiving a first message for the random access response on a control channel for a shared data channel, the first message comprising identification information for the random access preamble; and

receiving a second message for the random access response on the shared data channel, the second message comprising the control channel resources assigned to the UE.

18. An apparatus for wireless communication, comprising:

at least one processor configured to receive a random access preamble sent by a user equipment (UE) for system access, to send a random access response comprising control channel resources assigned to the UE, and to exchange control information with the UE using the assigned control channel resources; and

a memory coupled to the at least one processor.

19. The apparatus of claim 18, wherein the assigned control channel resources comprise at least one of channel quality indicator (CQI) resources used to send CQI on uplink by the UE and, power control (PC) resources used to send PC corrections on downlink to the UE.

20. The apparatus of claim 18, wherein the at least one processor is configured to send a first message for the random access response on a control channel for a shared data channel, and to send a second message for the random access response on the shared data channel, the first message comprising identification information for the random access preamble, and the second message comprising the control channel resources assigned to the UE.

21. An apparatus for wireless communication, comprising:

at least one processor configured to send a random access preamble for system access by a user equipment (UE), and to receive a random access response from a base station, the random access preamble comprising identification information, and the random access response being, asynchronous with respect to the random access preamble and addressing the random access preamble based on the identification information; and

a memory coupled to the at least one processor.

22. The apparatus of claim 21, wherein the at least one processor is configured to receive the random access response within a predetermined time window from when the random access preamble was sent.

23. The apparatus of claim 21, wherein the at least one processor is configured to select a random identifier (ID) for use as the identification information, and to receive the random access response comprising a temporary ID formed based on the random ID.

24. The apparatus of claim 23, wherein the temporary ID is formed further based on system time when the random access preamble was sent.

25. The apparatus of claim 21, wherein the at least one processor is configured to select a random identifier (ID) for use as the identification information, to determine the random access preamble based on the random ID and additional information, and to receive the random access response comprising a random access preamble identifier for the random access preamble.

26. The apparatus of claim 21, wherein the at least one processor is configured to send the random access preamble on a random access channel selected from among a plurality of available random access channels, to receive a first message for the random access response on a control channel for a shared data channel, and to receive a second message for the random access response on the shared data channel, the first message comprising a Random Access Radio Network Temporary Identifier (RA-RNTI) for the selected random access channel, and the second message comprising a random access preamble identifier including the identification information.

27. The apparatus of claim 21, wherein the at least one processor is configured to receive an assigned random identifier (ID) for use as the identification information, to send the random access preamble comprising the assigned random ID, and to receive the random access response comprising a Cell Access Radio Network Temporary Identifier (C-RNTI) associated with me assigned random ID, the assigned random ID being selected from a pool of reserved random IDs.

28. A method for wireless communication, comprising:

sending a random access preamble for system access by a user equipment (UE), the random access preamble comprising identification information; and

receiving a random access response from a base station, the random access response being asynchronous with respect to the random access preamble and addressing the random access preamble based on the identification information.

29. The method of claim 28, further comprising:

obtaining a random identifier (ID) for use as the identification information, and wherein the random access response comprises a temporary ID formed based on the random ID.

30. The method of claim 28, wherein the sending the random access preamble comprises sending the random access preamble on a random access channel selected from among a plurality of available random access channels, and wherein the receiving the random access response comprises receiving a first message for the random access response on a control channel for a shared data channel, and receiving a second message for the random access response on the shared data channel, the first message comprising a Random Access Radio Network Temporary Identifier (RA-RNTI) for the selected random access channel, and the second message comprising a random access preamble identifier including the identification information.

31. An apparatus for wireless, communication, comprising:

at least one processor configured to receive a random access preamble sent by a user equipment (UE) for system access, and to send a random access response to the UE, the random access preamble comprising identification information, the random access response being asynchronous with respect to the random access preamble and addressing the random access preamble based on the identification information; and

a memory coupled to the at least one processor.

32. The apparatus of claim 31, wherein the at least one processor is configured to receive from the random access preamble a random identifier (ID) used as the identification information, to determine a temporary ID based on the random ID, and to send the random access response comprising the temporary ID.

33. The apparatus of claim 31, wherein the at least one processor is configured to receive the random access preamble on a random access channel selected from among a plurality of available random access channels, to send a first message for the random access response on a control channel for a shared data channel, and to send a second message for the random access response on the shared data channel, the first message comprising a Random Access Radio Network Temporary Identifier (RA-RNTI) for the selected random access channel, and the second message comprising a random access preamble identifier including the identification information.

34. An apparatus for wireless communication, comprising:

at least one processor configured to communicate with a first base station, to receive a random identifier (ID) for handover of a user equipment (UE) from the first base station to a second base station, and to send a random access preamble comprising the random ID to access the second base station, the random ID being used to identify the UE; and

a memory coupled to the at least one processor.

35. The apparatus of claim 34, wherein the at least one processor is configured to receive the random ID from the first base station, the random ID being selected from a pool of reserved random IDs.

36. The apparatus of claim 34, wherein the at least one processor is configured to receive a random access response comprising at least one of uplink resources assigned to the UE and timing advance to adjust transmit timing of the UE.

37. The apparatus of claim 34, wherein the at least one processor is configured to receive a random access response comprising a cyclic redundancy check (CRC) masked with a Cell Radio Network Temporary Identifier (C-RNTI) assigned to the UE.

38. The apparatus of claim 36, wherein the at least one processor is configured to exchange data with the second base station after receiving the random access response.

39. A method for wireless communication, comprising:

communicating with a first base station;

receiving a random identifier (ID) for handover of a user equipment (UE) from the first base station to a second base station; and

sending a random access preamble comprising the random ID to access the second base station, the random ID being used to identify the UE.

40. The method of claim 39, wherein the receiving the random ID comprises

receiving the random ID from the first base station, the random ID being selected from a pool of reserved random IDs.

41. The method of claim 39, further comprising:

receiving a random access response comprising at least one of uplink resources assigned to the UE and timing advance to adjust transmit timing of the UE.

42. An apparatus for Wireless communication, comprising:

at least one processor configured to receive from a first base station a random identifier (ID) assigned to a user equipment (UE) for handover from the first base station to a second base station, to receive from the UE a random access preamble comprising the random ID, to identify the random access preamble as being from the UE based on the random ID, and to send a random access response to the UE; and

a memory coupled to the at least one processor.

43. The apparatus of claim 42, wherein the at least one processor is configured to send at least one of uplink resources and timing advance for the UE in the random access response.

44. The apparatus of claim 42, wherein the at least one processor is configured to receive a Cell Radio Network Temporary Identifier (C-RNTI) for the UE from the first base station, to generate a cyclic redundancy check (CRC) for the random access response, to mask the CRC with the C-RNTI, and to send the masked CRC in the random access response to the UE.

45. An apparatus for wireless communication, comprising:

at least one processor configured to send a random access preamble from a user equipment (UE) to access a base station, to receive a random access response from the base station, to send to the base station a first message comprising a unique identifier (ID) for the UE, and to receive from the base station a second message addressed to the UE based on the unique ID; and

a memory coupled to the at least one processor.

46. The apparatus of claim 45, wherein the at least one processor is configured to determine the unique ID for the UE based on at least one of an International Mobile Subscriber Identity (IMSI), a Temporary Mobile Subscriber Identity (TMSI), a Cell Radio Network Temporary Identifier (C-RNTI), and a registration area ID assigned to the UE.

47. The apparatus of claim 45, wherein the at least one processor is configured to receive at least one of timing advance and uplink resources in the random access response, and to receive at least one of channel quality indicator (CQI) resources and power control (PC) resources in the second message.

48. The apparatus of claim 45, wherein the at least one processor is configured to operate in an idle state prior to sending the random access preamble, and to send the random access preamble to transition from the idle state to an active state.

49. The apparatus of claim 48, wherein the at least one processor is configured to exchange Layer 3 signaling with the base station after receiving the second message, and to exchange data with the base station after completing the Layer 3 signaling exchange.

50. The apparatus of claim 45, wherein the at least one processor is configured to send the random access preamble to perform handover to the base station, to send the first message comprising a Cell Radio Network Temporary Identifier (C-RNTI) as the unique ID for the UE, to receive control channel resources assigned to the UE in the second message, and to exchange data with the base station after receiving the second message.

51. The apparatus of claim 45, wherein the random access preamble and the random access response are sent without hybrid automatic retransmission (HARQ), and wherein the first and second messages are sent with HARQ.

52. A method for wireless communication, comprising:

sending a random access preamble from a user equipment (UE) to access a base station;

receiving a random access response from the base station;

sending to the base station a first message comprising a unique identifier (ID) for the UE; and

receiving from the base station a second message addressed to the UE based on the unique ID.

53. The method of claim 52, further comprising:

determining the unique ID for the UE based on at least one of an International Mobile Subscriber Identity (IMSI), a Temporary Mobile Subscriber Identity (TMSI), a Cell Radio Network Temporary Identifier (C-RNTI), and a registration area ID assigned to the UE.

54. The method of claim 52, wherein the random access preamble is sent to perform handover to the base station, wherein the unique ID for the UE comprises a Cell Radio Network Temporary Identifier (C-RNTI) assigned to the UE, the method further comprising:

receiving control channel resources assigned to the UE in the second message; and

exchanging data with the base station after receiving the second message.

55. An apparatus for wireless communication, comprising:

at least one processor configured to receive a random access preamble sent by a user equipment (UE) to access a base station, to send a random access response to the UE, to receive a first message comprising a unique identifier (ID) for the UE, and to send a second message addressed to the UE based on the unique ID; and

a memory coupled to the at least one processor.

56. The apparatus of claim 55, wherein the at least one processor is configured to receive at least one of an International Mobile Subscriber Identity (IMSI), a Temporary Mobile Subscriber Identity (TMSI), a Cell Radio Network Temporary Identifier (C-RNTI), and a registration area ID assigned to the UE as the unique ID for the UE.

57. The apparatus of claim 55, wherein the at least one processor is configured to receive the random access preamble from the UE for handover to the base station, to receive the first message comprising a Cell Radio Network Temporary Identifier (C-RNTI) as the unique ID for the UE, to send control channel resources assigned to the UE for the UE in the second message, and to exchange data with the UE after sending the second message.