Random Access Channel Design for Narrow Bandwidth Operation in a Wide Bandwidth System

• US 20130083749A1
• Filed: 09/27/2012
• Published: 04/04/2013
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Hao Xu, Jelena M Damnjanovic, Juan Montojo, Peter Gaal, Wanshi Chen
• Inventors: GAAL, Peter, CHEN, Wanshi, DAMNJANOVIC, Jelena M., MONTOJO, Juan, XU, Hao
• Granted Patent: US 9,232,540 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1861 Physical mapping arrangements for ACK signaling see also H04L5/0053
• CPC Class Codes: H04L 1/1896 ARQ related signaling
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0092 Indication of how the channel is divided
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/008 with additional processing of random access related information at receiving side
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

A method of wireless communication includes a random access channel configuration for narrow bandwidth operations within a wider LTE system bandwidth. A first random access channel (RACH) configuration is broadcast for a regular device. A second RACH configuration is broadcast for a narrow bandwidth device. The narrow bandwidth device operates in a narrower bandwidth than the regular device.

Claims

1. A method of wireless communication in a narrow bandwidth device of a wider bandwidth system, comprising:

broadcasting a first random access channel (RACH) configuration for a regular device; and

broadcasting a second RACH configuration for the narrow bandwidth device, the narrow bandwidth device operating in a narrower bandwidth than the regular device.

2. The method of claim 1, in which the narrow bandwidth device is a user equipment (UE).

3. The method of claim 1, in which the second RACH configuration includes physical random access channel (PRACH) configuration indices, PRACH root sequences, frequency positions and/or radio network temporary identifier (RNTI).

4. The method of claim 1, further comprising transmitting a RACH response within the narrower bandwidth.

5. The method of claim 4, in which the RACH response is signaled by:

a narrowband physical downlink control channel (ePDCCH) in the narrow bandwidth or with fixed allocations mapped to a narrow bandwidth RACH configuration.

6. The method of claim 1, further comprising transmitting a message to assign the narrow bandwidth device to a different narrow bandwidth.

7. The method of claim 1, further comprising assigning different uplink and downlink resources to the narrow bandwidth device.

8. The method of claim 1, further comprising transmitting a response to the narrow bandwidth device, the response indicating a new downlink narrow bandwidth.

9. The method of claim 1, further comprising assigning a transmit power, timer offset, and/or number of retransmissions to the narrow bandwidth device that is different from a regular device assignment.

10. A method of wireless communication by a narrow bandwidth device, operating in a system including a wider bandwidth, comprising:

receiving a random access channel (RACH) configuration in a defined narrow band different from a RACH configuration received by a regular user equipment (UE); and

transmitting in accordance with the received RACH configuration.

11. The method of claim 10, in which the narrow bandwidth device is a user equipment (UE).

12. The method of claim 10, further comprising receiving a message to assign the narrow bandwidth device to operate in a different narrow bandwidth.

13. The method of claim 10, further comprising receiving a message assigning a transmit power, timer offset, and/or number of retransmissions to the narrow bandwidth device that is different from a regular device assignment.

14. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory, the at least one processor being configured;

to broadcast a first random access channel (RACH) configuration for a regular device; and

to broadcast a second RACH configuration for the narrow bandwidth device, the narrow bandwidth device operating in a narrower bandwidth than the regular device.

15. The apparatus of claim 14, in which the narrow bandwidth device is a user equipment (UE).

16. The apparatus of claim 14, in which the second RACH configuration includes physical random access channel (PRACH) configuration indices, PRACH root sequences, frequency positions and/or radio network temporary identifier (RNTI).

17. The apparatus of claim 14, in which the at least one processor is further configured to transmit a RACH response within the narrower bandwidth.

18. The apparatus of claim 17, in which the RACH response is signaled by:

a narrowband physical downlink control channel (ePDCCH) in the narrow bandwidth or with fixed allocations mapped to a narrow bandwidth RACH configuration.

19. The apparatus of claim 14, in which the at least one processor is further configured to transmit a message to assign the narrow bandwidth device to a different narrow bandwidth.

20. The apparatus of claim 14, in which the at least one processor is further configured to assign different uplink and downlink resources to the narrow bandwidth device.

21. The apparatus of claim 14, in which the at least one processor is further configured to transmit a response to the narrow bandwidth device, the response indicating a new downlink narrow bandwidth.

22. The apparatus of claim 14, in which the at least one processor is further configured to assign a transmit power, timer offset, and/or number of retransmissions to the narrow bandwidth device that is different from a regular device assignment.

23. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory, the at least one processor being configured;

to receive a random access channel (RACH) configuration in a defined narrow band different from a RACH configuration received by a regular user equipment (UE); and

to transmitting in accordance with the received RACH configuration.

24. The apparatus of claim 23, in which the narrow bandwidth device is a user equipment (UE).

25. The apparatus of claim 23, in which the processor is further configured to receive a message to assign the narrow bandwidth device to operate in a different narrow bandwidth.

26. The apparatus of claim 23, in which the processor is further configured to receive a message assigning a transmit power, timer offset, and/or number of retransmissions to the narrow bandwidth device that is different from a regular device assignment.

27. An apparatus for wireless communication, comprising:

means for broadcasting a first random access channel (RACH) configuration for a regular device; and

means for broadcasting a second RACH configuration for the narrow bandwidth device, the narrow bandwidth device operating in a narrower bandwidth than the regular device.

28. An apparatus for wireless communication, comprising:

means for receiving a random access channel (RACH) configuration in a defined narrow band different from a RACH configuration received by a regular user equipment (UE); and

means for transmitting in accordance with the received RACH configuration.

29. A computer program product for wireless communication in a wireless network, comprising:

a non-transitory computer-readable medium having non-transitory program code recorded thereon, the program code comprising;

program code to broadcast a first random access channel (RACH) configuration for a regular device; and

program code to broadcast a second RACH configuration for the narrow bandwidth device, the narrow bandwidth device operating in a narrower bandwidth than the regular device.

30. A computer program product for wireless communication in a wireless network, comprising:

a non-transitory computer-readable medium having non-transitory program code recorded thereon, the program code comprising;

program code to receive a random access channel (RACH) configuration in a defined narrow band different from a RACH configuration received by a regular user equipment (UE); and

program code to transmit in accordance with the received RACH configuration.