CONTENTION-BASED TRANSMISSION WITH CONTENTION-FREE FEEDBACK FOR REDUCING LATENCY IN LTE ADVANCED NETWORKS AND ENHANCED PUCCH

• US 20110216722A1
• Filed: 03/04/2011
• Published: 09/08/2011
• Est. Priority Date: 03/05/2010
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel Corporation
• Inventors: Yang, Xiangying, Zhu, Yuan, Li, Qinghua
• Granted Patent: US 8,638,738 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H03M 13/09 Error detection only, e.g. using cyclic redundancy check [CRC] codes or single parity bit
• CPC Class Codes: H03M 13/29 combining two or more codes or code structures, e.g. product codes, generalised product codes, concatenated codes, inner and outer codes
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/0073 Special arrangements for feedback channel
• CPC Class Codes: H04L 2001/125 Arrangements for preventing errors in the return channel
• CPC Class Codes: H04L 2463/061 applying further key derivation, e.g. deriving traffic keys from a pair-wise master key cryptographic mechanisms or cryptographic arrangements for generation of secret information including derivation or calculation of cryptographic keys or passwords H04L9/0861
• CPC Class Codes: H04L 63/0876 based on the identity of the terminal or configuration, e.g. MAC address, hardware or software configuration or device fingerprint
• CPC Class Codes: H04W 12/062 Pre-authentication
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 36/0038 of security context information
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Methods for contention-based transmission with contention-free feedback for reduced latency in LTE Advanced networks and an enhanced PUCCH are generally disclosed herein. User equipment (UE) may transmit a contention sequence on a physical uplink control channel (PUCCH) to an enhanced-Node B (eNB) and may concurrently transmit data requesting uplink resources on a physical uplink shared channel (PUSCH) to the eNB. The contention sequence is transmitted on the PUCCH in accordance with a format that is assigned by the eNB. The contention sequence is either randomly selected by the UE or assigned by the eNB. When the contention sequence and data are not successfully received by the eNB, the UE may fall back to a more conventional random access channel (RACH) procedure for uplink resource allocation.

Claims

1. A method performed by user equipment (UE) for random access comprising:

transmitting a contention sequence on a first physical uplink channel to an enhanced-Node B (eNB); and

transmitting data requesting uplink resources on a second physical uplink channel to the eNB,

wherein the contention sequence is transmitted on the first physical uplink channel in accordance with a format that is assigned by the eNB, and

wherein the contention sequence is either randomly selected by the UE or assigned by the eNB.

2. The method of claim 1 wherein the first physical uplink channel is a physical uplink control channel (PUCCH) and the second physical uplink channel is a physical uplink shared channel (PUSCH), and

wherein the contention sequence is transmitted on the PUCCH and the data is concurrently transmitted on the PUSCH within a same subframe.

3. The method of claim 2 wherein when there is a restriction on concurrent transmissions within the same subframe by the UE, the contention sequence is transmitted on the PUCCH and the data is transmitted on the PUSCH and with a fixed time-offset therebetween.

4. The method of claim 3 wherein the data transmitted on the PUSCH is transmitted in accordance with a format of a unicast resource grant,

wherein the data includes identification (ID) information unique to the UE that was previously assigned by the eNB to allow the eNB to uniquely identify the UE that has transmitted the data on the PUSCH, and

wherein the data transmitted on the PUSCH indicates that the UE is requesting uplink channel resources for a subsequent uplink data transmission.

5. The method of claim 4 wherein when the eNB is unable to detect the data transmitted on the PUSCH but is able to detect the contention sequence:

the eNB is configured to follow a random-access channel (RACH) procedure when the contention sequence was randomly selected by the UE; and

the eNB is configured to follow a scheduling request (SR) procedure when the contention sequence was assigned to the UE.

6. The method of claim 2 wherein prior to the transmission of the contention sequence and the data, the method comprises receiving an allocation of resources of the PUCCH and the PUSCH from the eNB for use of the PUCCH and the PUSCH for random access.

7. The method of claim 6 wherein the allocation of resources is received by the UE in a downlink control channel from the eNB.

8. User equipment (UE) comprising physical-layer circuitry configured to:

transmit a contention sequence on a physical uplink control channel (PUCCH) to an enhanced-Node B (eNB); and

transmit data requesting uplink resources on a physical uplink shared channel (PUSCH) to the eNB,

wherein the data transmitted on the PUSCH indicates that the UE is requesting uplink channel resources for a subsequent uplink data transmission, and

wherein the contention sequence is transmitted on the PUCCH in accordance with a format that is assigned by the eNB.

9. The UE of claim 8 wherein the contention sequence is transmitted on the PUCCH and the data is concurrently transmitting on the PUSCH within a same subframe, and

when there is a restriction on concurrent transmissions within the same subframe by the UE, the contention sequence is transmitted on the PUCCH and the data is transmitted on the PUSCH and with a fixed time-offset therebetween.

10. The UE of claim 9 wherein the data transmitted on the PUSCH is transmitted in accordance with a format of a unicast resource grant,

wherein the data includes identification (ID) information unique to the UE that was previously assigned by the eNB to allow the eNB to uniquely identify the UE that has transmitted the data on the PUSCH.

11. The UE of claim 10 wherein when the eNB is unable to detect the data transmitted on the PUSCH but is able to detect the contention sequence:

the eNB is configured to follow a random-access channel (RACH) procedure when the contention sequence was randomly selected by the UE; and

the eNB is configured to follow a scheduling request (SR) procedure when the contention sequence was assigned to the UE.

12. The UE of claim 8 wherein prior to the transmission of the contention sequence and the data, the UE is configured to receive an allocation of resources of the PUCCH and the PUSCH from the eNB for use of the PUCCH and the PUSCH for random access, and

wherein the allocation of resources is received by the UE in a downlink control channel from the eNB.

13. The UE of claim 9 wherein eNB and the UE communicate over the PUCCH and the PUSCH in accordance with a Long Term Evolution (LTE)

Advanced standard of the third-generation partnership project (3GPP).

14. A method for random access by user equipment (UE), the method comprising:

transmitting a contention sequence in a reference signal portion of a physical uplink control channel (PUCCH) and data in a data portion of the PUCCH,

wherein the data is sent in one or more resource blocks (RBs) of the data portion of the PUCCH,

wherein two OFDM symbols are allocated for the reference signal portion for the transmission of the contention sequence.

15. The method of claim 14 wherein the contention sequence and the data are transmitted within a same subframe,

wherein the contention sequence is transmitted in accordance with a format that is assigned by an enhanced-Node B (eNB), and

wherein the contention sequence is either randomly selected by the UE or assigned by the eNB.

16. The method of claim 15 wherein the data transmitted on the PUCCH includes identification information unique to the UE that was previously assigned by the eNB to allow the eNB to uniquely identify the UE that has transmitted the data on the PUCCH, and

wherein the data transmitted on the PUCCH indicates that the UE is requesting uplink channel resources for a subsequent uplink data transmission.

17. The method of claim 14 wherein the UE communicates over the PUCCH and the PUSCH in accordance with a Long Term Evolution (LTE) Advanced standard of the third-generation partnership project (3GPP).

18. A method performed by an enhanced-Node B (eNB) for receiving on an enhanced physical uplink control channel (PUCCH),

wherein the PUCCH comprises first and second slots, each slot including three demodulation reference symbols (DMRS) and four data symbols,

wherein the method further comprises:

receiving thirty-six preamble sequences that are spread two-dimensionally over seventy-two subcarriers that carry the DMRS reference symbols; and

receiving a plurality of up to forty-five or more information bits of data over ninety-six subcarriers of the four data symbols.

19. The method of claim 18 further comprising:

detecting the preamble sequences over seventy-two subcarriers; and

using the preamble sequences as DMRS to coherently detect the information bits.

20. The method of claim 18 wherein the data includes:

Radio Network Temporary Identifiers (RNTI) of user equipment; and

signaling bits.

21. The method of claim 18 wherein the first and second slots comprise resource blocks of subcarriers that are located at opposite ends of a frequency band, and

wherein the eNB is configured to operate in accordance with a Long Term Evolution (LTE) Advanced standard of the third-generation partnership project (3GPP).