System and method for transmission in a grant-free uplink transmission scheme

• US 9,750,056 B2
• Filed: 01/27/2015
• Issued: 08/29/2017
• Est. Priority Date: 01/27/2015
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Au, Kelvin Kar Kin, Zhang, Liqing, Ma, Jianglei
• Primary Examiner(s): Moore, Jr., Michael J
• Application Number:
  US14/606,665
• Publication Number:
  US 20160219627A1
• Time in Patent Office: 945 Days
• CPC Class Codes: H04L 1/1861 Physical mapping arrangements for ACK signaling see also H04L5/0053
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 74/0841 with collision treatment

Abstract

A system and method includes implementing, by a base station (BS), a reliable ultra-low latency transmission mechanism in a grant-free uplink transmission scheme having defined therein contention transmission unit (CTU) access regions and a plurality of CTUs. Implementing the reliable ultra-low latency transmission mechanism includes defining a reliable ultra-low latency CTU (RULL-CTU) access region from a portion of the CTU access regions of the grant-free transmission scheme, defining an RULL-CTU mapping scheme by mapping at least a portion of plurality of CTUs to the RULL-CTU access region to define a plurality of RULL-CTUs, defining a reliable ultra-low latency user equipment (RULL-UE) mapping scheme by defining rules for mapping a plurality of RULL-UEs to the plurality of RULL-CTUs in an initial pattern for initial transmissions in a first transmission time interval (TTI), and a regrouped pattern for redundant transmissions in a second TTI subsequent to the first TTI.

Claims

1. A method comprising:

obtaining, by a first reliable ultra-low latency user equipment (RULL-UE), a first contention transmission unit (CTU) for an initial transmission in a first transmission time interval (TTI);

transmitting, by the first RULL-UE, to a base station (BS), the initial transmission on the first CTU during the first TTI;

obtaining, by the first RULL-UE, a second CTU for a redundant transmission in a second TTI subsequent to the first TTI; and

transmitting, to the BS, the redundant transmission on the second CTU during the second TTI without receiving acknowledgement/negative acknowledgement (ACK/NACK) feedback from the BS;

wherein the first CTU and the second CTU are basic transmission resources in a grant-free uplink transmission scheme, the grant-free uplink transmission scheme has a predefined initial pattern and a regrouped pattern, wherein the initial pattern has a mapping between a first group of RULL-UEs and a first group of CTUs for initial transmissions in the first TTI, and the regrouped pattern has a mapping between at least one UE of the first group of RULL-UEs and a second group of CTUs for redundant transmission in the second TTI.

23. The method of claim 1, wherein the initial pattern is different from the regrouped pattern.

24. The method of claim 23, wherein the first CTU in the first group of CTUs has a mapping with the first RULL-UE and a second RULL-UE, and the second CTU in the second group of CTUs has a mapping with the first RULL-UE or a combination of the first RULL-UE and a third RULL-UE.

25. The method of claim 1, further comprising:

transmitting, to the BS, a second redundant transmission on a third CTU during a third TTI without receiving ACK/NACK feedback from the BS.

26. The method of claim 25, wherein the third TTI is subsequent to the second TTI and the second TTI is subsequent to the first TTI.

27. The method of claim 1, further comprising:

receiving, from the BS, a high level signalling information, wherein the high level signalling information indicates the initial pattern and the regrouped pattern used by the first RULL-UE.

28. The method of claim 1, further comprising:

transmitting, to the BS, a connection setup signalling after the first RULL-UE initially accesses the BS.

29. The method of claim 1, where in the grant-free uplink transmission scheme comprises at least one RULL-CTU access region and at least one CTU access region, wherein each RULL-CTU access region comprises a plurality of RULL-CTUs.

30. The method of claim 1, wherein the regrouped pattern has a mapping between at least one UE of the first group of RULL-UEs and a second group of CTUs for redundant transmission in the second TTI, and the second group of CTUs has a mapping with a first portion of the first group of RULL-UEs for redundant transmission in the second TTI and another mapping with a first portion of a second group of RULL-UEs for initial transmission in the second TTI.

31. The method of claim 30, wherein the second group of CTUs has a second initial pattern for initial transmission of the second group of RULL-UEs, and the regrouped pattern partially overlaps the second group of CTUs with the second initial pattern.

2. A first reliable ultra-low latency user equipment (RULL-UE) comprising:

a hardware processor; and

a computer readable storage medium having stored thereon computer readable code for execution by the processor to cause the first RULL-UE to;

obtain a first contention transmission unit (CTU) for an initial transmission in a first transmission time interval (TTI);

transmit, to a base station (BS), the initial transmission on the first CTU during the first TTI;

obtain a second CTU for a redundant transmission in a second TTI subsequent to the first TTI; and

transmit, to the BS, the redundant transmission on the second CTU during the second TTI without receiving acknowledgement/negative acknowledgement (ACK/NACK) feedback from the BS;

wherein the first CTU and the second CTU are basic transmission resources in a grant-free uplink transmission scheme, the grant-free uplink transmission scheme has a predefined initial pattern and a regrouped pattern, wherein the initial pattern has a mapping between a first group of RULL-UEs and a first group of CTUs for initial transmissions in the first TTI, and the regrouped pattern has a mapping between at least one UE of the first group of RULL-UEs and a second group of CTUs for redundant transmission in the second TTI.

32. The first RULL-UE of claim 2, wherein the initial pattern is different from the regrouped pattern.

33. The first RULL-UE of claim 32, wherein the first CTU in the first group of CTUs has a mapping with the first RULL-UE and a second RULL-UE, and the second CTU in the second group of CTUs has a mapping with the first RULL-UE or a combination of the first RULL-UE and a third RULL-UE.

34. The first RULL-UE of claim 2, wherein the computer readable storage medium has stored thereon further computer readable code for execution by the processor to cause the first RULL-UE to:

transmit, to the BS, a second redundant transmission on a third CTU during a third TTI without receiving ACK/NACK feedback from the BS.

35. The first RULL-UE of claim 34, wherein the third TTI is subsequent to the second TTI and the second TTI is subsequent to the first TTI.

36. The first RULL-UE of claim 2, wherein the computer readable storage medium has stored thereon further computer readable code for execution by the processor to cause the first RULL-UE to:

receive, from the BS, a high level signalling information, wherein the high level signalling information indicates the initial pattern and the regrouped pattern used by the first RULL-UE.

37. The first RULL-UE of claim 2, wherein the computer readable storage medium has stored thereon further computer readable code for execution by the processor to cause the first RULL-UE to:

transmit, to the BS, a connection setup signalling after the first RULL-UE initially accesses the BS.

38. The first RULL-UE of claim 2, where in the grant-free uplink transmission scheme comprises at least one RULL-CTU access region and at least one CTU access region, wherein each RULL-CTU access region comprises a plurality of RULL-CTUs.

39. The first RULL-UE of claim 2, wherein the regrouped pattern has a mapping between at least one UE of the first group of RULL-UEs and a second group of CTUs for redundant transmission in the second TTI, and the second group of CTUs has a mapping with a first portion of the first group of RULL-UEs for redundant transmission in the second TTI and another mapping with a first portion of a second group of RULL-UEs for initial transmission in the second TTI.

40. The first RULL-UE of claim 39, wherein the second group of CTUs has a second initial pattern for initial transmission of the second group of RULL-UEs, and the regrouped pattern partially overlaps the second group of CTUs with the second initial pattern.

3. A method comprising:

receiving, by a base station (BS), an initial transmission on a first contention transmission unit (CTU) during a first transmission time interval (TTI) from a first reliable ultra-low latency user equipment (RULL-UE); and

receiving, by the BS, a redundant transmission on a second CTU during a second TTI from the first RULL-UE without sending acknowledgement/negative acknowledgement (ACK/NACK) feedback to the RULL-UE;

wherein the first CTU and the second CTU are basic transmission resources in a grant-free uplink transmission scheme, the grant-free uplink transmission scheme has a predefined initial pattern and a regrouped pattern, wherein the initial pattern has a mapping between a first group of RULL-UEs and a first group of CTUs for the initial transmissions in the first TTI, and the regrouped pattern has a mapping between at least one UE of the first group of RULL-UEs and a second group of CTUs for the redundant transmission in the second TTI.

4. The method of claim 3, wherein the initial pattern is different from the regrouped pattern.

5. The method of claim 4, wherein the first CTU in the first group of CTUs has a mapping with the first RULL-UE and a second RULL-UE, and the second CTU in the second group of CTUs has a mapping with the first RULL-UE or a combination of the first RULL-UE and a third RULL-UE.

6. The method of claim 3, further comprising:

receiving, by the BS, a second redundant transmission on a third CTU during a third TTI from the first RULL-UE without sending ACK/NACK feedback to the first RULL-UE.

7. The method of claim 6, wherein the third TTI is subsequent to the second TTI and the second TTI is subsequent to the first TTI.

8. The method of claim 3, further comprising:

sending, by the BS, a high level signalling information to the first RULL-UE, wherein the high level signalling information indicates the initial pattern and the regrouped pattern used by the first RULL-UE.

9. The method of claim 3, further comprising:

identifying, by the BS, the first RULL-UE based on a connection setup signalling after the first RULL-UE initially accesses the BS.

10. The method of claim 3, where in the grant-free uplink transmission scheme comprises at least one RULL-CTU access region and at least one CTU access region, wherein each RULL-CTU access region comprises a plurality of RULL-CTUs.

11. The method of claim 3, wherein the regrouped pattern has a mapping between at least one UE of the first group of RULL-UEs and a second group of CTUs for redundant transmission in the second TTI, and the second group of CTUs has a mapping with a first portion of the first group of RULL-UEs for redundant transmission in the second TTI and another mapping with a first portion of a second group of RULL-UEs for initial transmission in the second TTI.

12. The method of claim 11, wherein the second group of CTUs has a second initial pattern for initial transmission of the second group of RULL-UEs, and the regrouped pattern partially overlaps the second group of CTUs with the second initial pattern.

13. A base station (BS) comprising:

a hardware processor; and

a computer readable storage medium having stored thereon computer readable code for execution by the processor to cause the BS to;

receive an initial transmission on a first contention transmission unit (CTU) during a first transmission time interval (TTI) from a first reliable ultra-low latency user equipment (RULL-UE); and

receive a redundant transmission on a second CTU during a second TTI from the first RULL-UE without sending acknowledgement/negative acknowledgement (ACK/NACK) feedback to the RULL-UE;

wherein the first CTU and the second CTU are basic transmission resources in a grant-free uplink transmission scheme, the grant-free uplink transmission scheme has a predefined initial pattern and a regrouped pattern, wherein the initial pattern has a mapping between a first group of RULL-UEs and a first group of CTUs for the initial transmissions in the first TTI, and the regrouped pattern has a mapping between at least one UE of the first group of RULL-UEs and a second group of CTUs for the redundant transmission in the second TTI.

14. The BS of claim 13, wherein the initial pattern is different from the regrouped pattern.

15. The BS of claim 14, wherein the first CTU in the first group of CTUs has a mapping with the first RULL-UE and a second RULL-UE, and the second CTU in the second group of CTUs has a mapping with the first RULL-UE or a combination of the first RULL-UE and a third RULL-UE.

16. The BS of claim 13, wherein the computer readable storage medium has stored thereon further computer readable code for execution by the processor to cause the BS to:

receive a second redundant transmission on a third CTU during a third TTI from the first RULL-UE without sending ACK/NACK feedback to the first RULL-UE.

17. The BS of claim 16, wherein the third TTI is subsequent to the second TTI and the second TTI is subsequent to the first TTI.

18. The BS of claim 13, wherein the computer readable storage medium has stored thereon further computer readable code for execution by the processor to cause the BS to:

send a high level signalling information to the first RULL-UE, wherein the high level signalling information indicates the initial pattern and the regrouped pattern used by the first RULL-UE.

19. The BS of claim 13, wherein the computer readable storage medium has stored thereon further computer readable code for execution by the processor to cause the BS to:

identify the first RULL-UE based on a connection setup signalling after the first RULL-UE initially accesses the BS.

20. The BS of claim 13, where in the grant-free uplink transmission scheme comprises at least one RULL-CTU access region and at least one CTU access region, wherein each RULL-CTU access region comprises a plurality of RULL-CTUs.

21. The BS of claim 13, wherein the regrouped pattern has a mapping between at least one UE of the first group of RULL-UEs and a second group of CTUs for redundant transmission in the second TTI, and the second group of CTUs has a mapping with a first portion of the first group of RULL-UEs for redundant transmission in the second TTI and another mapping with a first portion of a second group of RULL-UEs for initial transmission in the second TTI.

22. The BS of claim 21, wherein the second group of CTUs has a second initial pattern for initial transmission of the second group of RULL-UEs, and the regrouped pattern partially overlaps the second group of CTUs with the second initial pattern.