CONTENTION FREE PHYSICAL UPLINK SHARED CONTROL CHANNEL (PUSCH) TRANSMISSION USING LISTEN BEFORE TALK

• US 20180302868A1
• Filed: 12/24/2015
• Published: 10/18/2018
• Est. Priority Date: 05/14/2015
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel IP Corporation (Intel Corporation)
• Inventors: BHORKAR, Abhijeet, IBARS CASAS, Christian, HAN, Seunghee
• Granted Patent: US 10,757,664 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]

Abstract

Technology for contention free physical uplink shared control channel (PUSCH) transmission using listen before talk procedure is disclosed. In an example, an apparatus of a user equipment (UE) having circuitry configured to achieves low latency synchronization with an anchor enhanced Node (eNB) by sensing for a predetermined time period if any physical uplink shared channels (PUSCH) are idle with the anchor eNB for uplink (UL) synchronization; providing a unique UE identification in a PUSCH transmission; and communicating the PUSCH transmission in one of the idle PUSCH channels for contention free communication with the anchor eNB for uplink synchronization.

Claims

1-32. -32. (canceled)

33. An apparatus of a user equipment (UE), the apparatus, under control of one or more processors and memory, to achieve low latency synchronization with an enhanced Node B (eNB), the apparatus configured to:

sense for a predetermined time period if any physical uplink shared channels (PUSCH) are idle;

provide a unique UE identification in a PUSCH transmission; and

communicate the PUSCH transmission in one of the idle PUSCH channels for contention free communication with the eNB for uplink synchronization.

34. The apparatus of claim 33, wherein the apparatus is further configured to communicate the PUSCH transmission in one of the idle PUSCH channels with the eNB without uplink synchronization scheduling.

35. The apparatus of claim 33, wherein the apparatus is further configured to sense a PUSCH channel is idle if a sensed energy is below a predefined threshold.

36. The apparatus of claim 33, wherein the apparatus is further configured to perform a clear channel assessment (CCA) or extended clear channel assessment (ECCA) for multiples sensing granularity slits known to the UE or perform the CCA or the ECCA by signaling the eNB.

37. The apparatus of claim 33, wherein the apparatus is further configured to sense if any of the PUSCH channels are idle during a clear channel assessment (CCA) and an extended CCA (ECCA), wherein a duration of the CCA or ECCA is based upon minimum sensing granularity.

38. The apparatus of claim 37, wherein the apparatus is further configured to sense a PUSCH channel is idle if a sensed energy is below a predefined threshold during the duration of the CCA or the ECCA.

39. The apparatus of claim 37, wherein the apparatus is further configured to:

perform the ECCA by spanning over a plurality of sensing granularity slits, wherein a number of the plurality of sensing granularity slits that the ECCA spans over is determined by a contention window (CW);

determine a number of the plurality of sensing granularity slits by generating a random number from 1 to the number of the plurality of sensing granularity slits determined by the CW that the ECCA spans over determined as a backoff counter; and

reduce the number of the plurality of sensing granularity slits that the ECCA spans over each time a PUSCH channel is sensed as idle.

40. The apparatus of claim 39, wherein the apparatus is further configured to:

reduce an ECCA counter by a factor of one (1) each time the PUSCH channel is sensed as idle;

process, for transmission, a reservation signal to align to the symbol boundary;

or

process, for transmission, the reservation signal to start a next symbol.

41. The apparatus of claim 40, wherein the apparatus is further configured to sense if a current transmission attempt is unsuccessful, wherein the UE continues to perform the ECCA in a subsequent subframe using a current counter of an ECCA counter without generating a new random number.

42. The apparatus of claim 41, wherein the apparatus is further configured to:

sense if a current transmission attempt is unsuccessful, wherein the UE performs a listen before talk procedure consisting of the CCA and the ECCA by regenerating a new backoff counter in the next transmission attempt; and

perform the listen before talk procedure starting at symbol 0 for a specified number of symbols M, wherein the PUSCH transmission starts from symbol M+1 and end at symbol 14 within the subframe, wherein M is a positive integer, wherein a sounding reference signal (SRS) is transmitted on the symbol 14, wherein puncturing of the symbol 14 is eliminated.

43. The apparatus of claim 33, wherein the apparatus is further configured to reserve one of the PUSCH channels that is idle for communicating the PUSCH transmission.

44. The apparatus of claim 43, wherein the unique UE identification is one of a cell radio network temporary identifier (C-RNTI) or a radio network temporary identifier (RNTI).

45. The apparatus of claim 33, wherein communicating the PUSCH transmission is performed upon arrival of an UL packet at a media access control (MAC) buffer of the UE.

46. The apparatus of claim 33, wherein the PUSCH transmission consists of a plurality of symbols corresponding to subcarriers in a resource block, wherein the circuitry is further configured to use at least one of the plurality of symbols for sensing the PUSCH channel is idle while using a remaining number of the plurality of symbols for the PUSCH transmission.

47. The apparatus of claim 33, wherein the apparatus is further configured to use Modulation Coding Scheme (MCS) for the UL transmission, wherein the MCS can be predefined by a lowest MCS.

48. The apparatus of claim 33, wherein the apparatus is further configured to use preamble signaling for sensing the PUSCH channels are idle.

49. The apparatus of claim 33, wherein the apparatus is further configured to use an additional preamble signal for sensing the PUSCH channels are idle, wherein the additional preamble signal includes a radio network temporary identifier (RNTI) or and a DMRS signal for demodulation, wherein the DMRS signal is removed during a PUSCH transmission burst.

50. The apparatus of claim 49, wherein the apparatus is further configured to communicate the PUSCH transmission in a hybrid automatic repeat request (HARQ) operation.

51. The apparatus of claim 50, wherein the apparatus is further configured to process, for retransmission, the PUSCH transmission upon the UE receiving a negative acknowledgment (NACK) in a physical HARQ indicator channel (PHICH).

52. The apparatus of claim 33, wherein the retransmission of the PUSCH transmission is based on UL grant or based on a new data indicator (NDI) toggling in the UL grant.

53. The apparatus of claim 33, wherein the apparatus is further configured to communicate the PUSCH transmission in a configured time or frequency region.

54. The apparatus of claim 33, wherein the apparatus is further configured to adaptively split the UE from an alternative UE into different contention zones having different contention windows, wherein each of the contention zones are dynamically or semi-statically adapted according to latency requirements.

55. The apparatus of claim 33, wherein the apparatus includes at least one of an antenna, a touch sensitive display screen, a speaker, a microphone, a graphics processor, an application processor, a baseband processor, an internal memory, a non-volatile memory port, and combinations thereof.

56. An apparatus of an anchored enhanced Node B (eNB) operable to achieve contention free uplink (UL) synchronization with a user equipment (UE), the apparatus configured to:

process a physical uplink shared channel (PUSCH) transmission, received from the UE, following the idle PUSCH channel sensing for a predetermined time period;

process a unique UE identification in the PUSCH transmission received by the eNB; and

determine an identify of the UE by the unique UE identification in the PUSCH transmission for the contention free UL synchronization.

57. The apparatus of claim 56, wherein the apparatus is further configured to perform a blind UE detection based on demodulation reference signal (DMRS).

58. The apparatus of claim 56, wherein the apparatus is further configured to generate a demodulation reference signal (DMRS) sequence using a Constant Amplitude Zero Autocorrelation Waveform (CAZAC) sequence, wherein the CAZAC sequence is a Zadoff-Chu (ZC) sequence.

59. The apparatus of claim 56, wherein the apparatus is further configured to process the PUSCH transmission that is received in one of the idle PUSCH channels from the UE without UL synchronization scheduling.

60. The apparatus of claim 56, wherein the apparatus is further configured to process a reserve signal, that is received from the UE, for reserving one of a plurality of PUSCH channels that is idle for receiving the PUSCH transmission.

61. The apparatus of claim 56, wherein the apparatus is further configured to receive from the UE the PUSCH transmission upon arrival of an UL packet at a media access control (MAC) buffer of the UE.

62. The apparatus of claim 56, wherein the apparatus is further configured to:

use Modulation Coding Scheme (MCS) for the UL transmission, wherein the MCS can be predefined by a lowest MCS;

process the PUSCH transmission received in a hybrid automatic repeat request (HARQ) operation; and

process, for transmission, a negative acknowledgment (NACK) in a physical HARQ indicator channel to the UE to trigger the UE to retransmit the PUSCH transmission.

63. The apparatus of claim 56, wherein the apparatus is further configured to:

process, for transmission, an UL grant or a new data indicator (NDI) toggling in the UL grant to the UE for the retransmission of the PUSCH transmission;

process the PUSCH transmission received in a configured time or frequency region; and

dynamically or semi-statically adapt or assign a contention window upon determining a cell collision between the UE and an alternative UE by creating a new contention zone having a different contention window or reducing a currently used contention zone for successfully receiving the PUSCH transmission.

64. An apparatus of an anchored enhanced Node B (eNB) operable to perform contention free uplink (UL) synchronization with a user equipment (UE), the apparatus configured to:

process a physical uplink shared channel (PUSCH) transmission, received from the UE, following the idle PUSCH channel sensing for a predetermined time period;

process a unique UE identification in the PUSCH transmission received by the eNB;

determine an identify of the UE by the unique UE identification in the PUSCH transmission for the contention free UL synchronization; and

perform a blind UE detection based on demodulation reference

65. The apparatus of claim 64, wherein the apparatus is further configured to receive from the UE the PUSCH transmission upon arrival of an UL packet at a media access control (MAC) buffer of the UE.