PHYSICAL RANDOM ACCESS CHANNEL (PRACH) TRANSMISSION IN MULTICARRIER OPERATION

• US 20130336260A1
• Filed: 08/16/2013
• Published: 12/19/2013
• Est. Priority Date: 09/12/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Damnjanovic, Jelena M., Montojo, Juan, Gaal, Peter, Chen, Wanshi, Ho, Sai Yiu Duncan
• Granted Patent: US 9,370,003 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access

Abstract

Systems and methodologies are described that facilitate selecting an uplink carrier for random access within a wireless environment having multiple carriers. Selection of an uplink carrier for random access can be randomly selected from a set of available uplink carriers. Additionally, the uplink carrier for random access can be selected based upon which uplink carrier is paired with an anchor carrier. Further, the uplink carrier for random access can be identified based upon a bandwidth related to the user equipment (UE). Reference signals can also be employed in order to identify an uplink carrier to perform random access.

Claims

1. A method for wireless communication that facilitates performing random access for multiple carriers in a wireless environment, comprising:

defining a set of Physical Random Access Channel (PRACH) parameters for each of at least one downlink (DL) carrier; and

identifying a downlink carrier acquired by a UE based upon the set of PRACH parameters defined and used by the UE to perform random access.

2. The method of claim 1, wherein the set of parameters includes at least a specific radio frame, a subframe within the radio frame, and a physical resource block in a frequency domain.

3. The method of claim of claim 1, further comprising:

transmitting a random access response on the identified downlink carrier.

4. The method of claim 1, further comprising:

determining a downlink carrier among the at least one downlink carrier;

selecting an uplink carrier corresponding to the downlink carrier as the uplink carrier to be used for random access; and

notifying a UE about the uplink carrier selection to perform the random access.

5. The method of claim 4, wherein determining the downlink carrier further comprises selecting a cell and a downlink carrier for random access based on at least one of reference signal measurements, channel quality feedback, and loading information for detectable cells.

6. A wireless communications apparatus, comprising:

at least one processor configured to;

define a set of Physical Random Access Channel (PRACH) parameters for each of at least one downlink (DL) carrier; and

identify a downlink carrier acquired by a UE based upon the set of PRACH parameters defined and used by the UE to perform random access.

7. The wireless communications apparatus of claim 6, wherein the set of parameters includes at least a specific radio frame, a subframe within the radio frame, and a physical resource block in a frequency domain.

8. The wireless communications apparatus of claim 6, further comprising:

at least one processor configured to;

transmit a random access response on the identified downlink carrier.

9. The wireless communications apparatus of claim 6, further comprising:

at least one processor configured to;

determine a downlink carrier among the at least one downlink carrier;

select an uplink carrier corresponding to the downlink carrier as the uplink carrier to be used for random access; and

notify a UE about the uplink carrier selection to perform the random access.

10. The wireless communications apparatus of claim 9, wherein determining the downlink carrier further comprises selecting a cell and a downlink carrier for random access based on at least one of reference signal measurements, channel quality feedback, and loading information for detectable cells.

11. A wireless communications apparatus that performs random access for multiple carriers in a wireless environment, comprising:

means for defining a set of Physical Random Access Channel (PRACH) parameters for each of at least one downlink (DL) carrier; and

means for identifying a downlink carrier acquired by a UE based upon the set of PRACH parameters defined and used by the UE to perform random access.

12. The wireless communications apparatus of claim 11, wherein the set of parameters includes at least a specific radio frame, a subframe within the radio frame, and a physical resource block in a frequency domain.

13. The wireless communications apparatus of claim 11, further comprising:

means for transmitting a random access response on the identified downlink carrier.

14. The wireless communications apparatus of claim 11, further comprising:

means for determining a downlink carrier among the at least one downlink carrier;

means for selecting an uplink carrier corresponding to the downlink carrier as the uplink carrier to be used for random access; and

means for notify a UE about the uplink carrier selection to perform the random access.

15. The wireless communications apparatus of claim 14, wherein the means for determining the downlink carrier further comprises means for selecting a cell and a downlink carrier for random access based on at least one of reference signal measurements, channel quality feedback, and loading information for detectable cells.

16. A computer program product comprising a non-transitory computer-readable medium comprising:

code for causing at least one computer to define a set of Physical Random Access Channel (PRACH) parameters for each of at least one downlink (DL) carrier; and

code for causing at least one computer to identify a downlink carrier acquired by a UE based upon the set of PRACH parameters defined and used by the UE to perform random access.

17. The computer program product of claim 16, wherein the set of parameters includes at least a specific radio frame, a subframe within the radio frame, and a physical resource block in a frequency domain.

18. The computer program product of claim 16, further comprising:

code for causing at least one computer to transmit a random access response on the identified downlink carrier.

19. The computer program product of claim 16, further comprising:

code for causing at least one computer to determine a downlink carrier among the at least one downlink carrier;

code for causing at least one computer to select an uplink carrier corresponding to the downlink carrier as the uplink carrier to be used for random access; and

code for causing at least one computer to notify a UE about the uplink carrier selection to perform random access.

20. The computer program product of claim 19, wherein the code for causing at least one computer to determine the downlink carrier further comprises code for causing at least one computer to select a cell and a downlink carrier for random access based on at least one of reference signal measurements, channel quality feedback, and loading information for detectable cells.